Orthopedics

Unicompartmental knee arthroplasty (UKA) is considered a less invasive approach for the treatment of unicompartmental knee arthritis when compared with total knee arthroplasty (TKA), with optimal preservation of kinematics.¹ Despite excellent functional outcomes, conversion to TKA may be necessary if the UKA fails, or in patients with progressive knee arthritis. Some studies have found UKA conversion to TKA to be comparable with primary TKA,^2,3 whereas others have found that conversion often requires bone graft, augments, and stemmed components and has increased complications and inferior results compared to primary TKA.^4-7 While some studies report that <10% of UKA conversions to TKA require augments,² others have found that as many as 76% require augments.^4-8

Schwarzkopf and colleagues⁹ recently demonstrated that UKA conversion to TKA is comparable with primary TKA when a conservative tibial resection is performed during the index procedure. However, they reported increased complexity when greater tibial resection was performed and thicker polyethylene inserts were used at the time of the index UKA. The odds ratio of needing an augment or stem during the conversion to TKA was 26.8 (95% confidence interval, 3.71-194) when an aggressive tibial resection was performed during the UKA.⁹ Tibial resection thickness may thus be predictive of anticipated complexity of UKA revision to TKA and may aid in preoperative planning.

Robotic assistance has been shown to enhance the accuracy of bone preparation, implant component alignment, and soft tissue balance in UKA.^10-15 It has yet to be determined whether this improved accuracy translates to improved clinical performance or longevity of the UKA implant. However, the enhanced accuracy of robotic technology may result in more conservative tibial resection when compared to conventional UKA and may be advantageous if conversion to TKA becomes necessary.

The purpose of this study was to compare the distribution of polyethylene insert sizes implanted during conventional and robotic-assisted UKA. We hypothesized that robotic assistance would demonstrate more conservative tibial resection compared to conventional methods of bone preparation.

Methods

We retrospectively compared the distribution of polyethylene insert sizes implanted during consecutive conventional and robotic-assisted UKA procedures. Several manufacturers were queried to provide a listing of the polyethylene insert sizes utilized, ranging from 8 mm to 14 mm. The analysis included 8421 robotic-assisted UKA cases and 27,989 conventional UKA cases. Data were provided by Zimmer Biomet and Smith & Nephew regarding conventional cases, as well as Blue Belt Technologies (now part of Smith & Nephew) and MAKO Surgical (now part of Stryker) regarding robotic-assisted cases. (Dr. Lonner has an ongoing relationship as a consultant with Blue Belt Technologies, whose data was utilized in this study.) Using tibial insert thickness as a surrogate measure of the extent of tibial resection, an insert size of ≥10 mm was defined as aggressive while <10 mm was considered conservative. This cutoff was established based on its corresponding resection level with primary TKA and the anticipated need for augments. Statistical analysis was performed using a Mann-Whitney-Wilcoxon test. Significance was set at P < .05.

Results

Tibial resection thickness was found to be most commonly conservative in nature, with sizes 8-mm and 9-mm polyethylene inserts utilized in the majority of both robotic-assisted and conventional UKA cases. However, statistically more 8-mm and 9-mm polyethylene inserts were used in the robotic group (93.6%) than in the conventional group (84.5%) (P < .0001; Figure). Aggressive tibial resection, requiring tibial inserts ≥10 mm, was performed in 6.4% of robotic-assisted cases and 15.5% of conventional cases.

Discussion

Robotic assistance enhances the accuracy of bone preparation, implant component alignment, and soft tissue balance in UKA.^10-15 It has yet to be determined whether this improved accuracy translates to improved clinical performance or longevity of the UKA implant. However, we demonstrate that the enhanced accuracy of robotic technology results in more conservative tibial resection when compared to conventional techniques with a potential benefit suggested in the literature upon conversion to TKA.

The findings of this study have important implications for patients undergoing conversion of UKA to TKA, potentially optimizing the ease of revision and clinical outcomes. The outcomes of UKA conversion to TKA are often considered inferior to those of primary TKA, compromised by bone loss, need for augmentation, and challenges of restoring the joint line and rotation.^9,16-22 Barrett and Scott¹⁸ reported only 66% of patients had good or excellent results at an average of 4.6 years of follow-up after UKA conversion to TKA. Over 50% required stemmed implants and bone graft or bone cement augmentation to address osseous insufficiency. The authors suggested that the primary determinant of the complexity of the conversion to TKA was the surgical technique used in the index procedure. They concluded that UKA conversion to TKA can be as successful as a primary TKA and primary TKA implants can be used without bone augmentation or stems during the revision procedure if minimal tibial bone is resected at the time of the index UKA.¹⁸ Schwarzkopf and colleagues⁹ supported this conclusion when they found that aggressive tibial resection during UKA resulted in the need for bone graft, stem, wedge, or augment in 70% of cases when converted to TKA. Similarly, Khan and colleagues²³ found that 26% of patients required bone grafting and 26% required some form of augmentation, and Springer and colleagues³ reported that 68% required a graft, augment, or stem.^3,22 Using data from the New Zealand Joint Registry, Pearse and colleagues⁵ reported that revision TKA components were necessary in 28% of patients and concluded that converting a UKA to TKA gives a less reliable result than primary TKA, and with functional results that are not significantly better than a revision from a TKA.

Conservative tibial resection during UKA minimizes the complexity and concerns of bone loss upon conversion to TKA. Schwarzkopf and colleagues⁹ found 96.6% of patients with conservative tibial resection received a primary TKA implant, without augments or stems. Furthermore, patients with a primary TKA implant showed improved tibial survivorship, with revision as an end point, compared with patients who received a TKA implant that required stems and augments or bone graft for support.⁹ Also emphasizing the importance of minimal tibial resection, O’Donnell and colleagues⁸ compared a cohort of patients undergoing conversion of a minimal resection resurfacing onlay-type UKA to TKA with a cohort of patients undergoing primary TKA. They found that 40% of patients required bone grafting for contained defects, 3.6% required metal augments, and 1.8% required stems.⁸ There was no significant difference between the groups in terms of range of motion, functional outcome, or radiologic outcomes. The authors concluded that revision of minimal resection resurfacing implants to TKA is associated with similar results to primary TKA and is superior to revision of UKA with greater bone loss. Prior studies have shown that one of the advantages of robotic-assisted UKA is the accuracy and precision of bone resection. The present study supports this premise by showing that tibial resection is significantly more conservative using robotic-assisted techniques when using tibial component thickness as a surrogate for extent of bone resection. While our study did not address implant durability or the impact of conservative resection on conversion to TKA, studies referenced above suggest that the conservative nature of bone preparation would have a relevant impact on the revision of the implant to TKA.

Our study is a retrospective case series that reports tibial component thickness as a surrogate for volume of tibial resection during UKA. While the implication is that more conservative tibial resection may optimize durability and ease of conversion to TKA, future study will be needed to compare robotic-assisted and conventional cases of UKA upon conversion to TKA in order to ascertain whether the more conventional resections of robotic-assisted UKA in fact lead to revision that is comparable with primary TKA in terms of bone loss at the time of revision, components utilized, the need for bone graft, augments, or stems, and clinical outcomes. Given the method of data collection in this study, we could not control for clinical deformity, selection bias, surgeon experience, or medial vs lateral knee compartments. These potential confounders represent weaknesses of this study.

In conclusion, conversion of UKA to TKA may be associated with significant osseous insufficiency, which may compromise patient outcomes in comparison to primary TKA. Studies have shown that UKA conversion to TKA is comparable to primary TKA when minimal tibial resection is performed during the UKA, and the need for augmentation, grafting or stems is increased with more aggressive tibial resection. This study has shown that when robotic assistance is utilized, tibial resection is more precise, less variable, and more conservative compared to conventional techniques.

Am J Orthop. 2016;45(7):E465-E468. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Unicompartmental knee arthroplasty (UKA) is considered a less invasive approach for the treatment of unicompartmental knee arthritis when compared with total knee arthroplasty (TKA), with optimal preservation of kinematics.¹ Despite excellent functional outcomes, conversion to TKA may be necessary if the UKA fails, or in patients with progressive knee arthritis. Some studies have found UKA conversion to TKA to be comparable with primary TKA,^2,3 whereas others have found that conversion often requires bone graft, augments, and stemmed components and has increased complications and inferior results compared to primary TKA.^4-7 While some studies report that <10% of UKA conversions to TKA require augments,² others have found that as many as 76% require augments.^4-8

Schwarzkopf and colleagues⁹ recently demonstrated that UKA conversion to TKA is comparable with primary TKA when a conservative tibial resection is performed during the index procedure. However, they reported increased complexity when greater tibial resection was performed and thicker polyethylene inserts were used at the time of the index UKA. The odds ratio of needing an augment or stem during the conversion to TKA was 26.8 (95% confidence interval, 3.71-194) when an aggressive tibial resection was performed during the UKA.⁹ Tibial resection thickness may thus be predictive of anticipated complexity of UKA revision to TKA and may aid in preoperative planning.

Robotic assistance has been shown to enhance the accuracy of bone preparation, implant component alignment, and soft tissue balance in UKA.^10-15 It has yet to be determined whether this improved accuracy translates to improved clinical performance or longevity of the UKA implant. However, the enhanced accuracy of robotic technology may result in more conservative tibial resection when compared to conventional UKA and may be advantageous if conversion to TKA becomes necessary.

The purpose of this study was to compare the distribution of polyethylene insert sizes implanted during conventional and robotic-assisted UKA. We hypothesized that robotic assistance would demonstrate more conservative tibial resection compared to conventional methods of bone preparation.

Methods

We retrospectively compared the distribution of polyethylene insert sizes implanted during consecutive conventional and robotic-assisted UKA procedures. Several manufacturers were queried to provide a listing of the polyethylene insert sizes utilized, ranging from 8 mm to 14 mm. The analysis included 8421 robotic-assisted UKA cases and 27,989 conventional UKA cases. Data were provided by Zimmer Biomet and Smith & Nephew regarding conventional cases, as well as Blue Belt Technologies (now part of Smith & Nephew) and MAKO Surgical (now part of Stryker) regarding robotic-assisted cases. (Dr. Lonner has an ongoing relationship as a consultant with Blue Belt Technologies, whose data was utilized in this study.) Using tibial insert thickness as a surrogate measure of the extent of tibial resection, an insert size of ≥10 mm was defined as aggressive while <10 mm was considered conservative. This cutoff was established based on its corresponding resection level with primary TKA and the anticipated need for augments. Statistical analysis was performed using a Mann-Whitney-Wilcoxon test. Significance was set at P < .05.

Results

Tibial resection thickness was found to be most commonly conservative in nature, with sizes 8-mm and 9-mm polyethylene inserts utilized in the majority of both robotic-assisted and conventional UKA cases. However, statistically more 8-mm and 9-mm polyethylene inserts were used in the robotic group (93.6%) than in the conventional group (84.5%) (P < .0001; Figure). Aggressive tibial resection, requiring tibial inserts ≥10 mm, was performed in 6.4% of robotic-assisted cases and 15.5% of conventional cases.

Discussion

Robotic assistance enhances the accuracy of bone preparation, implant component alignment, and soft tissue balance in UKA.^10-15 It has yet to be determined whether this improved accuracy translates to improved clinical performance or longevity of the UKA implant. However, we demonstrate that the enhanced accuracy of robotic technology results in more conservative tibial resection when compared to conventional techniques with a potential benefit suggested in the literature upon conversion to TKA.

The findings of this study have important implications for patients undergoing conversion of UKA to TKA, potentially optimizing the ease of revision and clinical outcomes. The outcomes of UKA conversion to TKA are often considered inferior to those of primary TKA, compromised by bone loss, need for augmentation, and challenges of restoring the joint line and rotation.^9,16-22 Barrett and Scott¹⁸ reported only 66% of patients had good or excellent results at an average of 4.6 years of follow-up after UKA conversion to TKA. Over 50% required stemmed implants and bone graft or bone cement augmentation to address osseous insufficiency. The authors suggested that the primary determinant of the complexity of the conversion to TKA was the surgical technique used in the index procedure. They concluded that UKA conversion to TKA can be as successful as a primary TKA and primary TKA implants can be used without bone augmentation or stems during the revision procedure if minimal tibial bone is resected at the time of the index UKA.¹⁸ Schwarzkopf and colleagues⁹ supported this conclusion when they found that aggressive tibial resection during UKA resulted in the need for bone graft, stem, wedge, or augment in 70% of cases when converted to TKA. Similarly, Khan and colleagues²³ found that 26% of patients required bone grafting and 26% required some form of augmentation, and Springer and colleagues³ reported that 68% required a graft, augment, or stem.^3,22 Using data from the New Zealand Joint Registry, Pearse and colleagues⁵ reported that revision TKA components were necessary in 28% of patients and concluded that converting a UKA to TKA gives a less reliable result than primary TKA, and with functional results that are not significantly better than a revision from a TKA.

Conservative tibial resection during UKA minimizes the complexity and concerns of bone loss upon conversion to TKA. Schwarzkopf and colleagues⁹ found 96.6% of patients with conservative tibial resection received a primary TKA implant, without augments or stems. Furthermore, patients with a primary TKA implant showed improved tibial survivorship, with revision as an end point, compared with patients who received a TKA implant that required stems and augments or bone graft for support.⁹ Also emphasizing the importance of minimal tibial resection, O’Donnell and colleagues⁸ compared a cohort of patients undergoing conversion of a minimal resection resurfacing onlay-type UKA to TKA with a cohort of patients undergoing primary TKA. They found that 40% of patients required bone grafting for contained defects, 3.6% required metal augments, and 1.8% required stems.⁸ There was no significant difference between the groups in terms of range of motion, functional outcome, or radiologic outcomes. The authors concluded that revision of minimal resection resurfacing implants to TKA is associated with similar results to primary TKA and is superior to revision of UKA with greater bone loss. Prior studies have shown that one of the advantages of robotic-assisted UKA is the accuracy and precision of bone resection. The present study supports this premise by showing that tibial resection is significantly more conservative using robotic-assisted techniques when using tibial component thickness as a surrogate for extent of bone resection. While our study did not address implant durability or the impact of conservative resection on conversion to TKA, studies referenced above suggest that the conservative nature of bone preparation would have a relevant impact on the revision of the implant to TKA.

Our study is a retrospective case series that reports tibial component thickness as a surrogate for volume of tibial resection during UKA. While the implication is that more conservative tibial resection may optimize durability and ease of conversion to TKA, future study will be needed to compare robotic-assisted and conventional cases of UKA upon conversion to TKA in order to ascertain whether the more conventional resections of robotic-assisted UKA in fact lead to revision that is comparable with primary TKA in terms of bone loss at the time of revision, components utilized, the need for bone graft, augments, or stems, and clinical outcomes. Given the method of data collection in this study, we could not control for clinical deformity, selection bias, surgeon experience, or medial vs lateral knee compartments. These potential confounders represent weaknesses of this study.

In conclusion, conversion of UKA to TKA may be associated with significant osseous insufficiency, which may compromise patient outcomes in comparison to primary TKA. Studies have shown that UKA conversion to TKA is comparable to primary TKA when minimal tibial resection is performed during the UKA, and the need for augmentation, grafting or stems is increased with more aggressive tibial resection. This study has shown that when robotic assistance is utilized, tibial resection is more precise, less variable, and more conservative compared to conventional techniques.

Am J Orthop. 2016;45(7):E465-E468. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Unicompartmental knee arthroplasty (UKA) is considered a less invasive approach for the treatment of unicompartmental knee arthritis when compared with total knee arthroplasty (TKA), with optimal preservation of kinematics.¹ Despite excellent functional outcomes, conversion to TKA may be necessary if the UKA fails, or in patients with progressive knee arthritis. Some studies have found UKA conversion to TKA to be comparable with primary TKA,^2,3 whereas others have found that conversion often requires bone graft, augments, and stemmed components and has increased complications and inferior results compared to primary TKA.^4-7 While some studies report that <10% of UKA conversions to TKA require augments,² others have found that as many as 76% require augments.^4-8

Schwarzkopf and colleagues⁹ recently demonstrated that UKA conversion to TKA is comparable with primary TKA when a conservative tibial resection is performed during the index procedure. However, they reported increased complexity when greater tibial resection was performed and thicker polyethylene inserts were used at the time of the index UKA. The odds ratio of needing an augment or stem during the conversion to TKA was 26.8 (95% confidence interval, 3.71-194) when an aggressive tibial resection was performed during the UKA.⁹ Tibial resection thickness may thus be predictive of anticipated complexity of UKA revision to TKA and may aid in preoperative planning.

Robotic assistance has been shown to enhance the accuracy of bone preparation, implant component alignment, and soft tissue balance in UKA.^10-15 It has yet to be determined whether this improved accuracy translates to improved clinical performance or longevity of the UKA implant. However, the enhanced accuracy of robotic technology may result in more conservative tibial resection when compared to conventional UKA and may be advantageous if conversion to TKA becomes necessary.

The purpose of this study was to compare the distribution of polyethylene insert sizes implanted during conventional and robotic-assisted UKA. We hypothesized that robotic assistance would demonstrate more conservative tibial resection compared to conventional methods of bone preparation.

Methods

We retrospectively compared the distribution of polyethylene insert sizes implanted during consecutive conventional and robotic-assisted UKA procedures. Several manufacturers were queried to provide a listing of the polyethylene insert sizes utilized, ranging from 8 mm to 14 mm. The analysis included 8421 robotic-assisted UKA cases and 27,989 conventional UKA cases. Data were provided by Zimmer Biomet and Smith & Nephew regarding conventional cases, as well as Blue Belt Technologies (now part of Smith & Nephew) and MAKO Surgical (now part of Stryker) regarding robotic-assisted cases. (Dr. Lonner has an ongoing relationship as a consultant with Blue Belt Technologies, whose data was utilized in this study.) Using tibial insert thickness as a surrogate measure of the extent of tibial resection, an insert size of ≥10 mm was defined as aggressive while <10 mm was considered conservative. This cutoff was established based on its corresponding resection level with primary TKA and the anticipated need for augments. Statistical analysis was performed using a Mann-Whitney-Wilcoxon test. Significance was set at P < .05.

Results

Tibial resection thickness was found to be most commonly conservative in nature, with sizes 8-mm and 9-mm polyethylene inserts utilized in the majority of both robotic-assisted and conventional UKA cases. However, statistically more 8-mm and 9-mm polyethylene inserts were used in the robotic group (93.6%) than in the conventional group (84.5%) (P < .0001; Figure). Aggressive tibial resection, requiring tibial inserts ≥10 mm, was performed in 6.4% of robotic-assisted cases and 15.5% of conventional cases.

Discussion

Robotic assistance enhances the accuracy of bone preparation, implant component alignment, and soft tissue balance in UKA.^10-15 It has yet to be determined whether this improved accuracy translates to improved clinical performance or longevity of the UKA implant. However, we demonstrate that the enhanced accuracy of robotic technology results in more conservative tibial resection when compared to conventional techniques with a potential benefit suggested in the literature upon conversion to TKA.

The findings of this study have important implications for patients undergoing conversion of UKA to TKA, potentially optimizing the ease of revision and clinical outcomes. The outcomes of UKA conversion to TKA are often considered inferior to those of primary TKA, compromised by bone loss, need for augmentation, and challenges of restoring the joint line and rotation.^9,16-22 Barrett and Scott¹⁸ reported only 66% of patients had good or excellent results at an average of 4.6 years of follow-up after UKA conversion to TKA. Over 50% required stemmed implants and bone graft or bone cement augmentation to address osseous insufficiency. The authors suggested that the primary determinant of the complexity of the conversion to TKA was the surgical technique used in the index procedure. They concluded that UKA conversion to TKA can be as successful as a primary TKA and primary TKA implants can be used without bone augmentation or stems during the revision procedure if minimal tibial bone is resected at the time of the index UKA.¹⁸ Schwarzkopf and colleagues⁹ supported this conclusion when they found that aggressive tibial resection during UKA resulted in the need for bone graft, stem, wedge, or augment in 70% of cases when converted to TKA. Similarly, Khan and colleagues²³ found that 26% of patients required bone grafting and 26% required some form of augmentation, and Springer and colleagues³ reported that 68% required a graft, augment, or stem.^3,22 Using data from the New Zealand Joint Registry, Pearse and colleagues⁵ reported that revision TKA components were necessary in 28% of patients and concluded that converting a UKA to TKA gives a less reliable result than primary TKA, and with functional results that are not significantly better than a revision from a TKA.

Conservative tibial resection during UKA minimizes the complexity and concerns of bone loss upon conversion to TKA. Schwarzkopf and colleagues⁹ found 96.6% of patients with conservative tibial resection received a primary TKA implant, without augments or stems. Furthermore, patients with a primary TKA implant showed improved tibial survivorship, with revision as an end point, compared with patients who received a TKA implant that required stems and augments or bone graft for support.⁹ Also emphasizing the importance of minimal tibial resection, O’Donnell and colleagues⁸ compared a cohort of patients undergoing conversion of a minimal resection resurfacing onlay-type UKA to TKA with a cohort of patients undergoing primary TKA. They found that 40% of patients required bone grafting for contained defects, 3.6% required metal augments, and 1.8% required stems.⁸ There was no significant difference between the groups in terms of range of motion, functional outcome, or radiologic outcomes. The authors concluded that revision of minimal resection resurfacing implants to TKA is associated with similar results to primary TKA and is superior to revision of UKA with greater bone loss. Prior studies have shown that one of the advantages of robotic-assisted UKA is the accuracy and precision of bone resection. The present study supports this premise by showing that tibial resection is significantly more conservative using robotic-assisted techniques when using tibial component thickness as a surrogate for extent of bone resection. While our study did not address implant durability or the impact of conservative resection on conversion to TKA, studies referenced above suggest that the conservative nature of bone preparation would have a relevant impact on the revision of the implant to TKA.

Our study is a retrospective case series that reports tibial component thickness as a surrogate for volume of tibial resection during UKA. While the implication is that more conservative tibial resection may optimize durability and ease of conversion to TKA, future study will be needed to compare robotic-assisted and conventional cases of UKA upon conversion to TKA in order to ascertain whether the more conventional resections of robotic-assisted UKA in fact lead to revision that is comparable with primary TKA in terms of bone loss at the time of revision, components utilized, the need for bone graft, augments, or stems, and clinical outcomes. Given the method of data collection in this study, we could not control for clinical deformity, selection bias, surgeon experience, or medial vs lateral knee compartments. These potential confounders represent weaknesses of this study.

In conclusion, conversion of UKA to TKA may be associated with significant osseous insufficiency, which may compromise patient outcomes in comparison to primary TKA. Studies have shown that UKA conversion to TKA is comparable to primary TKA when minimal tibial resection is performed during the UKA, and the need for augmentation, grafting or stems is increased with more aggressive tibial resection. This study has shown that when robotic assistance is utilized, tibial resection is more precise, less variable, and more conservative compared to conventional techniques.

Am J Orthop. 2016;45(7):E465-E468. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The modern term orthopedics stems from the older word orthopedia, which was the title of a book published in 1741 by Nicholas Andry, a professor of medicine at the University of Paris.¹ The term orthopedia is a composite of 2 Greek words: orthos, meaning “straight and free from deformity,” and paidios, meaning “child.” Together, orthopedics literally means straight child, suggesting the importance of pediatric injuries and deformities in the development of this field. Interestingly, Andry’s book also depicted a crooked young tree attached to a straight and strong staff, which has become the universal symbol of orthopedic surgery and underscores the focus on correcting deformities in the young (Figure).¹

Orthopedic surgery is a rapidly advancing medical field with several recent advances noted within orthopedic subspecialties,^2-4 basic science,⁵ and clinical research.⁶ It is important to recognize the role of history with regards to innovation and research, especially for young trainees and medical students interested in a particular medical specialty. More specifically, it is important to understand the successes and failures of the past in order to advance research and practice, and ultimately improve patient care and outcomes.

In the recent literature, there is no concise yet comprehensive article focusing on the history of orthopedic surgery. The goal of this review is to provide an overview of the history and development of orthopedic surgery from ancient practices to the modern era.

Ancient Orthopedics

While the evidence is limited, the practice of orthopedics dates back to the primitive man.⁷ Fossil evidence suggests that the orthopedic pathology of today, such as fractures and traumatic amputations, existed in primitive times.⁸ The union of fractures in fair alignment has also been observed, which emphasizes the efficacy of nonoperative orthopedics and suggests the early use of splints and rehabilitation practices.^8,9 Since procedures such as trepanation and crude amputations occurred during the New Stone Age, it is feasible that sophisticated techniques had also been developed for the treatment of injuries.^7-9 However, evidence continues to remain limited.⁷

Later civilizations also developed creative ways to manage orthopedic injuries. For example, the Shoshone Indians, who were known to exist around 700-2000 BCE, made a splint of fresh rawhide that had been soaked in water.^9,10 Similarly, some South Australian tribes made splints of clay, which when dried were as good as plaster of Paris.⁹ Furthermore, bone-setting or reductions was practiced as a profession in many tribes, underscoring the importance of orthopedic injuries in early civilizations.^8,9

Ancient Egypt

The ancient Egyptians seemed to have carried on the practices of splinting. For example, 2 splinted specimens were discovered during the Hearst Egyptian Expedition in 1903.⁷ More specifically, these specimens included a femur and forearm and dated to approximately 300 BCE.⁷ Other examples of splints made of bamboo and reed padded with linen have been found on mummies as well.⁸ Similarly, crutches were also used by this civilization, as depicted on a carving made on an Egyptian tomb in 2830 BCE.⁸

One of the earliest and most significant documents on medicine was discovered in 1862, known as the Edwin Smith papyrus. This document is thought to have been composed by Imhotep, a prominent Egyptian physician, astrologer, architect, and politician, and it specifically categorizes diseases and treatments. Many scholars recognize this medical document as the oldest surgical textbook.^11,12 With regards to orthopedic conditions, this document describes the reduction of a dislocated mandible, signs of spinal or vertebral injuries, description of torticollis, and the treatment of fractures such as clavicle fractures.⁸ This document also discusses ryt, which refers to the purulent discharge from osteomyelitis.⁸ The following is an excerpt from this ancient document:⁹

“Instructions on erring a break in his upper arm…Thou shouldst spread out with his two shoulders in order to stretch apart his upper arm until that break falls into its place. Thou shouldst make for him two splints of linen, and thou shouldst apply for him one of them both on the inside of his arm, and the other of them both on the underside of his arm.”

This account illustrates the methodical and meticulous nature of this textbook, and it highlights some of the essentials of medical practice from diagnosis to medical decision-making to treatment.

There are various other contributions to the field of medicine from the Far East; however, many of these pertain to the fields of plastic surgery and general surgery.⁹

Greeks and Romans

The Greeks are considered to be the first to systematically employ the scientific approach to medicine.⁸ In the period between 430 BCE to 330 BCE, the Corpus Hippocrates was compiled, which is a Greek text on medicine. It is named for Hippocrates (460 BCE-370 BCE), the father of medicine, and it contains text that applies specifically to the field of orthopedic surgery. For example, this text discuses shoulder dislocations and describes various reduction maneuvers. Hippocrates had a keen understanding of the principles of traction and countertraction, especially as it pertains to the musculoskeletal system.⁸ In fact, the Hippocratic method is still used for reducing anterior shoulder dislocations, and its description can be found in several modern orthopedic texts, including recent articles.¹³ The Corpus Hippocrates also describes the correction of clubfoot deformity, and the treatment of infected open fractures with pitch cerate and wine compresses.⁸

Hippocrates also described the treatment of fractures, the principles of traction, and the implications of malunions. For example, Hippocrates wrote, “For the arm, when shortened, might be concealed and the mistake will not be great, but a shortened thigh bone will leave a man maimed.”¹ In addition, spinal deformities were recognized by the Greeks, and Hippocrates devised an extension bench for the correction of such deformities.¹ From their contributions to anatomy and surgical practice, the Greeks have made significant contributions to the field of surgery.⁹

During the Roman period, another Greek surgeon by the name of Galen described the musculoskeletal and nervous systems. He served as a gladiatorial surgeon in Rome, and today, he is considered to be the father of sports medicine.⁸ He is also credited with coining the terms scoliosis, kyphosis, and lordosis to denote the spinal deformities that were first described by Hippocrates.¹ In the Roman period, amputations were also performed, and primitive prostheses were developed.⁹

The Middle Ages

There was relatively little progress in the study of medicine for a thousand years after the fall of the Roman Empire.⁹ This stagnation was predominantly due to the early Christian Church inhibiting freedom of thought and observation, as well as prohibiting human dissection and the study of anatomy. The first medical school in Europe was established in Salerno, Italy, during the ninth century. This school provided primarily pedantic teaching to its students and perpetuated the theories of the elements and humors. Later on, the University of Bologna became one of the first academic institutions to offer hands-on surgical training.⁹ One of the most famous surgeons of the Middle Ages was Guy de Chuauliac, who studied at Montpellier and Bologna. He was a leader in the ethical principles of surgery as well as the practice of surgery, and wrote the following with regards to femur fractures:⁹

“After the application of splints, I attach to the foot a mass of lead as a weight, taking care to pass the cord which supports the weight over a small pulley in such a manner that it shall pull on the leg in a horizontal direction.”

This description is strikingly similar to the modern-day nonoperative management of femur fractures, and underscores the importance of traction, which as mentioned above, was first described by Hippocrates.

Eventually, medicine began to separate from the Church, most likely due to an increase in the complexity of medical theories, the rise of secular universities, and an increase in medical knowledge from Eastern and Middle-Eastern groups.⁹

The Renaissance and the Foundations of Modern Orthopedics

Until the 16^th century, the majority of medical theories were heavily influenced by the work of Hippocrates.⁸ The scientific study of anatomy gained prominence during this time, especially due to the work done by great artists, such as Leonardo Di Vinci.⁹ The Table

After a period of rapid expansion of the field of orthopedics, and following the Renaissance, many hospitals were built focusing on the sick and disabled, which solidified orthopedics’ position as a major medical specialty.¹ For example, in 1863, James Knight founded the Hospital for the Ruptured and Crippled in New York City. This hospital became the oldest orthopedic hospital in the United States, and it later became known as the Hospital for Special Surgery.^14,15 Several additional orthopedic institutions were formed, including the New York Orthopedic Dispensary in 1886 and Hospital for Deformities and Joint Diseases in 1917. Orthopedic surgery residency programs also began to be developed in the late 1800s.¹⁴ More specifically, Virgil Gibney at Hospital for the Ruptured and Crippled began the first orthopedic training program in the United States in 1888. Young doctors in this program trained for 1 year as junior assistant, senior assistant, and house surgeon, and began to be known as resident doctors.¹⁴

The Modern Era

In the 20th century, rapid development continued to better control infections as well as develop and introduce novel technology. For example, the invention of x-ray in 1895 by Wilhelm Conrad Röntgen improved our ability to diagnose and manage orthopedic conditions ranging from fractures to avascular necrosis of the femoral head to osteoarthritis.^8,14 Spinal surgery also developed rapidly with Russell Hibbs describing a technique for spinal fusion at the New York Orthopedic Hospital.⁸ Similarly, the World Wars served as a catalyst in the development of the subspecialty of orthopedic trauma, with increasing attention placed on open wounds and proficiency with amputations, internal fixation, and wound care. In 1942, Austin Moore performed the first metal hip arthroplasty, and the field of joint replacement was subsequently advanced by the work of Sir John Charnley in the 1960s.⁸

Conclusion

Despite its relatively recent specialization, orthopedic surgery has a rich history rooted in ancient practices dating back to the primitive man. Over time, there has been significant development in the field in terms of surgical and nonsurgical treatment of orthopedic pathology and disease. Various cultures have played an instrumental role in developing this field, and it is remarkable to see that several practices have persisted since the time of these ancient civilizations. During the Renaissance, there was a considerable emphasis placed on pediatric deformity, but orthopedic surgeons have now branched out to subspecialty practice ranging from orthopedic trauma to joint replacement to oncology.¹ For students of medicine and orthopedics, it is important to learn about the origins of this field and to appreciate its gradual development. Orthopedic surgery is a diverse and fascinating field that will most likely continue to develop with increased subspecialization and improved research at the molecular and population level. With a growing emphasis placed on outcomes and healthcare cost by today’s society, it will be fascinating to see how this field continues to evolve in the future.

Am J Orthop. 2016;45(7):E434-E438. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The modern term orthopedics stems from the older word orthopedia, which was the title of a book published in 1741 by Nicholas Andry, a professor of medicine at the University of Paris.¹ The term orthopedia is a composite of 2 Greek words: orthos, meaning “straight and free from deformity,” and paidios, meaning “child.” Together, orthopedics literally means straight child, suggesting the importance of pediatric injuries and deformities in the development of this field. Interestingly, Andry’s book also depicted a crooked young tree attached to a straight and strong staff, which has become the universal symbol of orthopedic surgery and underscores the focus on correcting deformities in the young (Figure).¹

Orthopedic surgery is a rapidly advancing medical field with several recent advances noted within orthopedic subspecialties,^2-4 basic science,⁵ and clinical research.⁶ It is important to recognize the role of history with regards to innovation and research, especially for young trainees and medical students interested in a particular medical specialty. More specifically, it is important to understand the successes and failures of the past in order to advance research and practice, and ultimately improve patient care and outcomes.

In the recent literature, there is no concise yet comprehensive article focusing on the history of orthopedic surgery. The goal of this review is to provide an overview of the history and development of orthopedic surgery from ancient practices to the modern era.

Ancient Orthopedics

While the evidence is limited, the practice of orthopedics dates back to the primitive man.⁷ Fossil evidence suggests that the orthopedic pathology of today, such as fractures and traumatic amputations, existed in primitive times.⁸ The union of fractures in fair alignment has also been observed, which emphasizes the efficacy of nonoperative orthopedics and suggests the early use of splints and rehabilitation practices.^8,9 Since procedures such as trepanation and crude amputations occurred during the New Stone Age, it is feasible that sophisticated techniques had also been developed for the treatment of injuries.^7-9 However, evidence continues to remain limited.⁷

Later civilizations also developed creative ways to manage orthopedic injuries. For example, the Shoshone Indians, who were known to exist around 700-2000 BCE, made a splint of fresh rawhide that had been soaked in water.^9,10 Similarly, some South Australian tribes made splints of clay, which when dried were as good as plaster of Paris.⁹ Furthermore, bone-setting or reductions was practiced as a profession in many tribes, underscoring the importance of orthopedic injuries in early civilizations.^8,9

Ancient Egypt

The ancient Egyptians seemed to have carried on the practices of splinting. For example, 2 splinted specimens were discovered during the Hearst Egyptian Expedition in 1903.⁷ More specifically, these specimens included a femur and forearm and dated to approximately 300 BCE.⁷ Other examples of splints made of bamboo and reed padded with linen have been found on mummies as well.⁸ Similarly, crutches were also used by this civilization, as depicted on a carving made on an Egyptian tomb in 2830 BCE.⁸

One of the earliest and most significant documents on medicine was discovered in 1862, known as the Edwin Smith papyrus. This document is thought to have been composed by Imhotep, a prominent Egyptian physician, astrologer, architect, and politician, and it specifically categorizes diseases and treatments. Many scholars recognize this medical document as the oldest surgical textbook.^11,12 With regards to orthopedic conditions, this document describes the reduction of a dislocated mandible, signs of spinal or vertebral injuries, description of torticollis, and the treatment of fractures such as clavicle fractures.⁸ This document also discusses ryt, which refers to the purulent discharge from osteomyelitis.⁸ The following is an excerpt from this ancient document:⁹

“Instructions on erring a break in his upper arm…Thou shouldst spread out with his two shoulders in order to stretch apart his upper arm until that break falls into its place. Thou shouldst make for him two splints of linen, and thou shouldst apply for him one of them both on the inside of his arm, and the other of them both on the underside of his arm.”

This account illustrates the methodical and meticulous nature of this textbook, and it highlights some of the essentials of medical practice from diagnosis to medical decision-making to treatment.

There are various other contributions to the field of medicine from the Far East; however, many of these pertain to the fields of plastic surgery and general surgery.⁹

Greeks and Romans

The Greeks are considered to be the first to systematically employ the scientific approach to medicine.⁸ In the period between 430 BCE to 330 BCE, the Corpus Hippocrates was compiled, which is a Greek text on medicine. It is named for Hippocrates (460 BCE-370 BCE), the father of medicine, and it contains text that applies specifically to the field of orthopedic surgery. For example, this text discuses shoulder dislocations and describes various reduction maneuvers. Hippocrates had a keen understanding of the principles of traction and countertraction, especially as it pertains to the musculoskeletal system.⁸ In fact, the Hippocratic method is still used for reducing anterior shoulder dislocations, and its description can be found in several modern orthopedic texts, including recent articles.¹³ The Corpus Hippocrates also describes the correction of clubfoot deformity, and the treatment of infected open fractures with pitch cerate and wine compresses.⁸

Hippocrates also described the treatment of fractures, the principles of traction, and the implications of malunions. For example, Hippocrates wrote, “For the arm, when shortened, might be concealed and the mistake will not be great, but a shortened thigh bone will leave a man maimed.”¹ In addition, spinal deformities were recognized by the Greeks, and Hippocrates devised an extension bench for the correction of such deformities.¹ From their contributions to anatomy and surgical practice, the Greeks have made significant contributions to the field of surgery.⁹

During the Roman period, another Greek surgeon by the name of Galen described the musculoskeletal and nervous systems. He served as a gladiatorial surgeon in Rome, and today, he is considered to be the father of sports medicine.⁸ He is also credited with coining the terms scoliosis, kyphosis, and lordosis to denote the spinal deformities that were first described by Hippocrates.¹ In the Roman period, amputations were also performed, and primitive prostheses were developed.⁹

The Middle Ages

There was relatively little progress in the study of medicine for a thousand years after the fall of the Roman Empire.⁹ This stagnation was predominantly due to the early Christian Church inhibiting freedom of thought and observation, as well as prohibiting human dissection and the study of anatomy. The first medical school in Europe was established in Salerno, Italy, during the ninth century. This school provided primarily pedantic teaching to its students and perpetuated the theories of the elements and humors. Later on, the University of Bologna became one of the first academic institutions to offer hands-on surgical training.⁹ One of the most famous surgeons of the Middle Ages was Guy de Chuauliac, who studied at Montpellier and Bologna. He was a leader in the ethical principles of surgery as well as the practice of surgery, and wrote the following with regards to femur fractures:⁹

“After the application of splints, I attach to the foot a mass of lead as a weight, taking care to pass the cord which supports the weight over a small pulley in such a manner that it shall pull on the leg in a horizontal direction.”

This description is strikingly similar to the modern-day nonoperative management of femur fractures, and underscores the importance of traction, which as mentioned above, was first described by Hippocrates.

Eventually, medicine began to separate from the Church, most likely due to an increase in the complexity of medical theories, the rise of secular universities, and an increase in medical knowledge from Eastern and Middle-Eastern groups.⁹

The Renaissance and the Foundations of Modern Orthopedics

Until the 16^th century, the majority of medical theories were heavily influenced by the work of Hippocrates.⁸ The scientific study of anatomy gained prominence during this time, especially due to the work done by great artists, such as Leonardo Di Vinci.⁹ The Table

After a period of rapid expansion of the field of orthopedics, and following the Renaissance, many hospitals were built focusing on the sick and disabled, which solidified orthopedics’ position as a major medical specialty.¹ For example, in 1863, James Knight founded the Hospital for the Ruptured and Crippled in New York City. This hospital became the oldest orthopedic hospital in the United States, and it later became known as the Hospital for Special Surgery.^14,15 Several additional orthopedic institutions were formed, including the New York Orthopedic Dispensary in 1886 and Hospital for Deformities and Joint Diseases in 1917. Orthopedic surgery residency programs also began to be developed in the late 1800s.¹⁴ More specifically, Virgil Gibney at Hospital for the Ruptured and Crippled began the first orthopedic training program in the United States in 1888. Young doctors in this program trained for 1 year as junior assistant, senior assistant, and house surgeon, and began to be known as resident doctors.¹⁴

The Modern Era

In the 20th century, rapid development continued to better control infections as well as develop and introduce novel technology. For example, the invention of x-ray in 1895 by Wilhelm Conrad Röntgen improved our ability to diagnose and manage orthopedic conditions ranging from fractures to avascular necrosis of the femoral head to osteoarthritis.^8,14 Spinal surgery also developed rapidly with Russell Hibbs describing a technique for spinal fusion at the New York Orthopedic Hospital.⁸ Similarly, the World Wars served as a catalyst in the development of the subspecialty of orthopedic trauma, with increasing attention placed on open wounds and proficiency with amputations, internal fixation, and wound care. In 1942, Austin Moore performed the first metal hip arthroplasty, and the field of joint replacement was subsequently advanced by the work of Sir John Charnley in the 1960s.⁸

Conclusion

Despite its relatively recent specialization, orthopedic surgery has a rich history rooted in ancient practices dating back to the primitive man. Over time, there has been significant development in the field in terms of surgical and nonsurgical treatment of orthopedic pathology and disease. Various cultures have played an instrumental role in developing this field, and it is remarkable to see that several practices have persisted since the time of these ancient civilizations. During the Renaissance, there was a considerable emphasis placed on pediatric deformity, but orthopedic surgeons have now branched out to subspecialty practice ranging from orthopedic trauma to joint replacement to oncology.¹ For students of medicine and orthopedics, it is important to learn about the origins of this field and to appreciate its gradual development. Orthopedic surgery is a diverse and fascinating field that will most likely continue to develop with increased subspecialization and improved research at the molecular and population level. With a growing emphasis placed on outcomes and healthcare cost by today’s society, it will be fascinating to see how this field continues to evolve in the future.

Am J Orthop. 2016;45(7):E434-E438. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The modern term orthopedics stems from the older word orthopedia, which was the title of a book published in 1741 by Nicholas Andry, a professor of medicine at the University of Paris.¹ The term orthopedia is a composite of 2 Greek words: orthos, meaning “straight and free from deformity,” and paidios, meaning “child.” Together, orthopedics literally means straight child, suggesting the importance of pediatric injuries and deformities in the development of this field. Interestingly, Andry’s book also depicted a crooked young tree attached to a straight and strong staff, which has become the universal symbol of orthopedic surgery and underscores the focus on correcting deformities in the young (Figure).¹

Orthopedic surgery is a rapidly advancing medical field with several recent advances noted within orthopedic subspecialties,^2-4 basic science,⁵ and clinical research.⁶ It is important to recognize the role of history with regards to innovation and research, especially for young trainees and medical students interested in a particular medical specialty. More specifically, it is important to understand the successes and failures of the past in order to advance research and practice, and ultimately improve patient care and outcomes.

In the recent literature, there is no concise yet comprehensive article focusing on the history of orthopedic surgery. The goal of this review is to provide an overview of the history and development of orthopedic surgery from ancient practices to the modern era.

Ancient Orthopedics

While the evidence is limited, the practice of orthopedics dates back to the primitive man.⁷ Fossil evidence suggests that the orthopedic pathology of today, such as fractures and traumatic amputations, existed in primitive times.⁸ The union of fractures in fair alignment has also been observed, which emphasizes the efficacy of nonoperative orthopedics and suggests the early use of splints and rehabilitation practices.^8,9 Since procedures such as trepanation and crude amputations occurred during the New Stone Age, it is feasible that sophisticated techniques had also been developed for the treatment of injuries.^7-9 However, evidence continues to remain limited.⁷

Later civilizations also developed creative ways to manage orthopedic injuries. For example, the Shoshone Indians, who were known to exist around 700-2000 BCE, made a splint of fresh rawhide that had been soaked in water.^9,10 Similarly, some South Australian tribes made splints of clay, which when dried were as good as plaster of Paris.⁹ Furthermore, bone-setting or reductions was practiced as a profession in many tribes, underscoring the importance of orthopedic injuries in early civilizations.^8,9

Ancient Egypt

The ancient Egyptians seemed to have carried on the practices of splinting. For example, 2 splinted specimens were discovered during the Hearst Egyptian Expedition in 1903.⁷ More specifically, these specimens included a femur and forearm and dated to approximately 300 BCE.⁷ Other examples of splints made of bamboo and reed padded with linen have been found on mummies as well.⁸ Similarly, crutches were also used by this civilization, as depicted on a carving made on an Egyptian tomb in 2830 BCE.⁸

One of the earliest and most significant documents on medicine was discovered in 1862, known as the Edwin Smith papyrus. This document is thought to have been composed by Imhotep, a prominent Egyptian physician, astrologer, architect, and politician, and it specifically categorizes diseases and treatments. Many scholars recognize this medical document as the oldest surgical textbook.^11,12 With regards to orthopedic conditions, this document describes the reduction of a dislocated mandible, signs of spinal or vertebral injuries, description of torticollis, and the treatment of fractures such as clavicle fractures.⁸ This document also discusses ryt, which refers to the purulent discharge from osteomyelitis.⁸ The following is an excerpt from this ancient document:⁹

“Instructions on erring a break in his upper arm…Thou shouldst spread out with his two shoulders in order to stretch apart his upper arm until that break falls into its place. Thou shouldst make for him two splints of linen, and thou shouldst apply for him one of them both on the inside of his arm, and the other of them both on the underside of his arm.”

This account illustrates the methodical and meticulous nature of this textbook, and it highlights some of the essentials of medical practice from diagnosis to medical decision-making to treatment.

There are various other contributions to the field of medicine from the Far East; however, many of these pertain to the fields of plastic surgery and general surgery.⁹

Greeks and Romans

The Greeks are considered to be the first to systematically employ the scientific approach to medicine.⁸ In the period between 430 BCE to 330 BCE, the Corpus Hippocrates was compiled, which is a Greek text on medicine. It is named for Hippocrates (460 BCE-370 BCE), the father of medicine, and it contains text that applies specifically to the field of orthopedic surgery. For example, this text discuses shoulder dislocations and describes various reduction maneuvers. Hippocrates had a keen understanding of the principles of traction and countertraction, especially as it pertains to the musculoskeletal system.⁸ In fact, the Hippocratic method is still used for reducing anterior shoulder dislocations, and its description can be found in several modern orthopedic texts, including recent articles.¹³ The Corpus Hippocrates also describes the correction of clubfoot deformity, and the treatment of infected open fractures with pitch cerate and wine compresses.⁸

Hippocrates also described the treatment of fractures, the principles of traction, and the implications of malunions. For example, Hippocrates wrote, “For the arm, when shortened, might be concealed and the mistake will not be great, but a shortened thigh bone will leave a man maimed.”¹ In addition, spinal deformities were recognized by the Greeks, and Hippocrates devised an extension bench for the correction of such deformities.¹ From their contributions to anatomy and surgical practice, the Greeks have made significant contributions to the field of surgery.⁹

During the Roman period, another Greek surgeon by the name of Galen described the musculoskeletal and nervous systems. He served as a gladiatorial surgeon in Rome, and today, he is considered to be the father of sports medicine.⁸ He is also credited with coining the terms scoliosis, kyphosis, and lordosis to denote the spinal deformities that were first described by Hippocrates.¹ In the Roman period, amputations were also performed, and primitive prostheses were developed.⁹

The Middle Ages

There was relatively little progress in the study of medicine for a thousand years after the fall of the Roman Empire.⁹ This stagnation was predominantly due to the early Christian Church inhibiting freedom of thought and observation, as well as prohibiting human dissection and the study of anatomy. The first medical school in Europe was established in Salerno, Italy, during the ninth century. This school provided primarily pedantic teaching to its students and perpetuated the theories of the elements and humors. Later on, the University of Bologna became one of the first academic institutions to offer hands-on surgical training.⁹ One of the most famous surgeons of the Middle Ages was Guy de Chuauliac, who studied at Montpellier and Bologna. He was a leader in the ethical principles of surgery as well as the practice of surgery, and wrote the following with regards to femur fractures:⁹

“After the application of splints, I attach to the foot a mass of lead as a weight, taking care to pass the cord which supports the weight over a small pulley in such a manner that it shall pull on the leg in a horizontal direction.”

This description is strikingly similar to the modern-day nonoperative management of femur fractures, and underscores the importance of traction, which as mentioned above, was first described by Hippocrates.

Eventually, medicine began to separate from the Church, most likely due to an increase in the complexity of medical theories, the rise of secular universities, and an increase in medical knowledge from Eastern and Middle-Eastern groups.⁹

The Renaissance and the Foundations of Modern Orthopedics

Until the 16^th century, the majority of medical theories were heavily influenced by the work of Hippocrates.⁸ The scientific study of anatomy gained prominence during this time, especially due to the work done by great artists, such as Leonardo Di Vinci.⁹ The Table

After a period of rapid expansion of the field of orthopedics, and following the Renaissance, many hospitals were built focusing on the sick and disabled, which solidified orthopedics’ position as a major medical specialty.¹ For example, in 1863, James Knight founded the Hospital for the Ruptured and Crippled in New York City. This hospital became the oldest orthopedic hospital in the United States, and it later became known as the Hospital for Special Surgery.^14,15 Several additional orthopedic institutions were formed, including the New York Orthopedic Dispensary in 1886 and Hospital for Deformities and Joint Diseases in 1917. Orthopedic surgery residency programs also began to be developed in the late 1800s.¹⁴ More specifically, Virgil Gibney at Hospital for the Ruptured and Crippled began the first orthopedic training program in the United States in 1888. Young doctors in this program trained for 1 year as junior assistant, senior assistant, and house surgeon, and began to be known as resident doctors.¹⁴

The Modern Era

In the 20th century, rapid development continued to better control infections as well as develop and introduce novel technology. For example, the invention of x-ray in 1895 by Wilhelm Conrad Röntgen improved our ability to diagnose and manage orthopedic conditions ranging from fractures to avascular necrosis of the femoral head to osteoarthritis.^8,14 Spinal surgery also developed rapidly with Russell Hibbs describing a technique for spinal fusion at the New York Orthopedic Hospital.⁸ Similarly, the World Wars served as a catalyst in the development of the subspecialty of orthopedic trauma, with increasing attention placed on open wounds and proficiency with amputations, internal fixation, and wound care. In 1942, Austin Moore performed the first metal hip arthroplasty, and the field of joint replacement was subsequently advanced by the work of Sir John Charnley in the 1960s.⁸

Conclusion

Despite its relatively recent specialization, orthopedic surgery has a rich history rooted in ancient practices dating back to the primitive man. Over time, there has been significant development in the field in terms of surgical and nonsurgical treatment of orthopedic pathology and disease. Various cultures have played an instrumental role in developing this field, and it is remarkable to see that several practices have persisted since the time of these ancient civilizations. During the Renaissance, there was a considerable emphasis placed on pediatric deformity, but orthopedic surgeons have now branched out to subspecialty practice ranging from orthopedic trauma to joint replacement to oncology.¹ For students of medicine and orthopedics, it is important to learn about the origins of this field and to appreciate its gradual development. Orthopedic surgery is a diverse and fascinating field that will most likely continue to develop with increased subspecialization and improved research at the molecular and population level. With a growing emphasis placed on outcomes and healthcare cost by today’s society, it will be fascinating to see how this field continues to evolve in the future.

Am J Orthop. 2016;45(7):E434-E438. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

A fracture occurring after anterior cruciate ligament (ACL) reconstruction is rare, and rarer still when it involves the harvest site of a bone—patellar tendon—bone (BPTB) autograft. The vast majority of fractures described in the literature are patellar, with the weak point along the patellar bone cut. A number of fractures generally also occur through the bone tunnels in both hamstring and BPTB grafts. However, only 2 cases of tibial tubercle fracture after BPTB graft have been published, and we expound on them in this case report.^1,2 The patient provided written informed consent for print and electronic publication of this case report.

Case Report

Eight years after undergoing successful left ACL reconstruction with ipsilateral BPTB graft, a 45-year-old man developed a graft rupture and demonstrated recurrent instability. He requested revision reconstruction, again with a BPTB construct. In the operating room, he was prepared and draped in the usual sterile fashion, and left ACL reconstruction was performed with right-knee central-third BPTB graft.

During surgery, the left knee was arthroscopically examined, and residual ACL graft from the initial reconstruction was removed. Notchplasty was performed, and the residual femoral interference screw was removed from the 12:30 position. A transtibial approach was used, with a 10-mm reamer brought through the proximal tibia, the posterior tibial ACL footprint, and the 2:00 distal femoral position, with 30 mm of femoral condyle drilled, leaving 1 mm of posterior femoral cortex.

After the right leg was exsanguinated, a central-third patellar tendon graft was harvested through a longitudinal incision with a 22-mm × 10-mm patellar plug, a 10-mm patellar graft, and a 22-mm × 11-mm tibial plug. The graft was prepared, the left tibia was overreamed, and the graft was passed. The graft was fixed with a 7-mm × 23-mm biointerference screw in the femur, trialed, and fixed with an 8-mm × 23-mm interference screw in the tibia. Excess bone graft was packed in the patellar defect in the right knee. The rent in the patellar tendon was closed. The rest of the incision was closed, and the patient was placed in an immobilizer and a cold therapy device (Polar Care; Breg, Inc).

At 2-week follow-up, the patient reported having slipped on ice and flexed the right knee, causing a pop, pain, and limitation in range of motion (ROM; 0°-70°).

Discussion

Cases of tibial tubercle fracture after BPTB autograft harvest are extremely rare in the published literature. PubMed and Cochrane Review searches revealed only 2—1 in the ipsilateral knee as ACL fixation¹ and 1 in the contralateral knee.² The middle third of the patellar tendon has been used for ACL reconstruction for more than 50 years, which supports the extreme rarity of this complication.³ Tibial tubercle fractures are so rare that they are not even mentioned in reviews of ACL complications.⁴ These fractures are universally treated with ORIF.^1,2

Far more common but still rare, fracture-type complications involve the extensor mechanism and the tibial plateau. Patellar fractures have been documented as occurring in 0.2% to 2.3% of cases.^5-7 One paper reported a fracture in 1.3% of cases at a mean of 57 days, with roughly half caused by trauma and the other half having atraumatic causes.⁸ Lee and colleagues⁹ found a 0.2% complication rate for all BPTB grafts in 1725 consecutive patients. Although some patients were treated nonoperatively, others underwent operative fixation. Time to clinical and radiographic healing was 7 and 10 weeks, respectively.

Tibial plateau fracture after BPTB harvest is a rare complication, with 11 cases reported in the literature.¹⁰ In 4 of those cases, the proposed mechanism of fracture was a stress riser resulting from the synergistic weakness of the tibial harvest site combined with the tibial tunnel reducing proximal tibial bone strength.^11-14 The mechanism of injury varied from traumatic to insufficiency fracture, with fixation varying with fracture displacement.

Tibial tubercle fracture after BPTB harvest is extremely rare, with the present case being only the third published in the literature. Like most reported post-ACL reconstruction extensor mechanism disruptions, our case resulted from a traumatic event at an interval after surgery. All other tibial tubercle fracture post-ACL reconstruction disruptions occurred within 2 weeks after surgery.^1,2 Sudden tension on the extensor mechanism secondary to hyperflexion caused a fracture through a weakened tibial tubercle with avulsion of the remaining tendon in 2 of the 3 cases, with the third being a lower stress popping noise that occurred during a pivot to stand.¹

The residual defect after tibial bone block harvest could represent a weakening of the tubercle by loss of structural bone and by development of stress risers. The previous reports of tibial tubercle fracture after BPTB harvest documented a similar methodology: Use a bone saw and osteotomes to harvest a trapezoidal tibial bone plug 10 mm to 11 mm wide and 22 cm to 35 cm long. As previously documented, we suggest taking care with saw cuts and osteotomes so as not to weaken the proximal tibia or distal patella more than is necessary.^1,2 Before surgery, patients should be warned about the possibility of extensor mechanism injuries with use of BPTB grafts.

Conclusion

Tibial tubercle fracture after BPTB harvest for ACL reconstruction is an extremely rare complication. Treatment is ORIF of the tubercle fragment, with a delay in ACL rehabilitation in cases involving the ipsilateral knee.

Am J Orthop. 2016;45(7):E469-E471. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

A fracture occurring after anterior cruciate ligament (ACL) reconstruction is rare, and rarer still when it involves the harvest site of a bone—patellar tendon—bone (BPTB) autograft. The vast majority of fractures described in the literature are patellar, with the weak point along the patellar bone cut. A number of fractures generally also occur through the bone tunnels in both hamstring and BPTB grafts. However, only 2 cases of tibial tubercle fracture after BPTB graft have been published, and we expound on them in this case report.^1,2 The patient provided written informed consent for print and electronic publication of this case report.

Case Report

Eight years after undergoing successful left ACL reconstruction with ipsilateral BPTB graft, a 45-year-old man developed a graft rupture and demonstrated recurrent instability. He requested revision reconstruction, again with a BPTB construct. In the operating room, he was prepared and draped in the usual sterile fashion, and left ACL reconstruction was performed with right-knee central-third BPTB graft.

During surgery, the left knee was arthroscopically examined, and residual ACL graft from the initial reconstruction was removed. Notchplasty was performed, and the residual femoral interference screw was removed from the 12:30 position. A transtibial approach was used, with a 10-mm reamer brought through the proximal tibia, the posterior tibial ACL footprint, and the 2:00 distal femoral position, with 30 mm of femoral condyle drilled, leaving 1 mm of posterior femoral cortex.

After the right leg was exsanguinated, a central-third patellar tendon graft was harvested through a longitudinal incision with a 22-mm × 10-mm patellar plug, a 10-mm patellar graft, and a 22-mm × 11-mm tibial plug. The graft was prepared, the left tibia was overreamed, and the graft was passed. The graft was fixed with a 7-mm × 23-mm biointerference screw in the femur, trialed, and fixed with an 8-mm × 23-mm interference screw in the tibia. Excess bone graft was packed in the patellar defect in the right knee. The rent in the patellar tendon was closed. The rest of the incision was closed, and the patient was placed in an immobilizer and a cold therapy device (Polar Care; Breg, Inc).

At 2-week follow-up, the patient reported having slipped on ice and flexed the right knee, causing a pop, pain, and limitation in range of motion (ROM; 0°-70°).

Discussion

Cases of tibial tubercle fracture after BPTB autograft harvest are extremely rare in the published literature. PubMed and Cochrane Review searches revealed only 2—1 in the ipsilateral knee as ACL fixation¹ and 1 in the contralateral knee.² The middle third of the patellar tendon has been used for ACL reconstruction for more than 50 years, which supports the extreme rarity of this complication.³ Tibial tubercle fractures are so rare that they are not even mentioned in reviews of ACL complications.⁴ These fractures are universally treated with ORIF.^1,2

Far more common but still rare, fracture-type complications involve the extensor mechanism and the tibial plateau. Patellar fractures have been documented as occurring in 0.2% to 2.3% of cases.^5-7 One paper reported a fracture in 1.3% of cases at a mean of 57 days, with roughly half caused by trauma and the other half having atraumatic causes.⁸ Lee and colleagues⁹ found a 0.2% complication rate for all BPTB grafts in 1725 consecutive patients. Although some patients were treated nonoperatively, others underwent operative fixation. Time to clinical and radiographic healing was 7 and 10 weeks, respectively.

Tibial plateau fracture after BPTB harvest is a rare complication, with 11 cases reported in the literature.¹⁰ In 4 of those cases, the proposed mechanism of fracture was a stress riser resulting from the synergistic weakness of the tibial harvest site combined with the tibial tunnel reducing proximal tibial bone strength.^11-14 The mechanism of injury varied from traumatic to insufficiency fracture, with fixation varying with fracture displacement.

Tibial tubercle fracture after BPTB harvest is extremely rare, with the present case being only the third published in the literature. Like most reported post-ACL reconstruction extensor mechanism disruptions, our case resulted from a traumatic event at an interval after surgery. All other tibial tubercle fracture post-ACL reconstruction disruptions occurred within 2 weeks after surgery.^1,2 Sudden tension on the extensor mechanism secondary to hyperflexion caused a fracture through a weakened tibial tubercle with avulsion of the remaining tendon in 2 of the 3 cases, with the third being a lower stress popping noise that occurred during a pivot to stand.¹

The residual defect after tibial bone block harvest could represent a weakening of the tubercle by loss of structural bone and by development of stress risers. The previous reports of tibial tubercle fracture after BPTB harvest documented a similar methodology: Use a bone saw and osteotomes to harvest a trapezoidal tibial bone plug 10 mm to 11 mm wide and 22 cm to 35 cm long. As previously documented, we suggest taking care with saw cuts and osteotomes so as not to weaken the proximal tibia or distal patella more than is necessary.^1,2 Before surgery, patients should be warned about the possibility of extensor mechanism injuries with use of BPTB grafts.

Conclusion

Tibial tubercle fracture after BPTB harvest for ACL reconstruction is an extremely rare complication. Treatment is ORIF of the tubercle fragment, with a delay in ACL rehabilitation in cases involving the ipsilateral knee.

Am J Orthop. 2016;45(7):E469-E471. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

A fracture occurring after anterior cruciate ligament (ACL) reconstruction is rare, and rarer still when it involves the harvest site of a bone—patellar tendon—bone (BPTB) autograft. The vast majority of fractures described in the literature are patellar, with the weak point along the patellar bone cut. A number of fractures generally also occur through the bone tunnels in both hamstring and BPTB grafts. However, only 2 cases of tibial tubercle fracture after BPTB graft have been published, and we expound on them in this case report.^1,2 The patient provided written informed consent for print and electronic publication of this case report.

Case Report

Eight years after undergoing successful left ACL reconstruction with ipsilateral BPTB graft, a 45-year-old man developed a graft rupture and demonstrated recurrent instability. He requested revision reconstruction, again with a BPTB construct. In the operating room, he was prepared and draped in the usual sterile fashion, and left ACL reconstruction was performed with right-knee central-third BPTB graft.

During surgery, the left knee was arthroscopically examined, and residual ACL graft from the initial reconstruction was removed. Notchplasty was performed, and the residual femoral interference screw was removed from the 12:30 position. A transtibial approach was used, with a 10-mm reamer brought through the proximal tibia, the posterior tibial ACL footprint, and the 2:00 distal femoral position, with 30 mm of femoral condyle drilled, leaving 1 mm of posterior femoral cortex.

After the right leg was exsanguinated, a central-third patellar tendon graft was harvested through a longitudinal incision with a 22-mm × 10-mm patellar plug, a 10-mm patellar graft, and a 22-mm × 11-mm tibial plug. The graft was prepared, the left tibia was overreamed, and the graft was passed. The graft was fixed with a 7-mm × 23-mm biointerference screw in the femur, trialed, and fixed with an 8-mm × 23-mm interference screw in the tibia. Excess bone graft was packed in the patellar defect in the right knee. The rent in the patellar tendon was closed. The rest of the incision was closed, and the patient was placed in an immobilizer and a cold therapy device (Polar Care; Breg, Inc).

At 2-week follow-up, the patient reported having slipped on ice and flexed the right knee, causing a pop, pain, and limitation in range of motion (ROM; 0°-70°).

Discussion

Cases of tibial tubercle fracture after BPTB autograft harvest are extremely rare in the published literature. PubMed and Cochrane Review searches revealed only 2—1 in the ipsilateral knee as ACL fixation¹ and 1 in the contralateral knee.² The middle third of the patellar tendon has been used for ACL reconstruction for more than 50 years, which supports the extreme rarity of this complication.³ Tibial tubercle fractures are so rare that they are not even mentioned in reviews of ACL complications.⁴ These fractures are universally treated with ORIF.^1,2

Far more common but still rare, fracture-type complications involve the extensor mechanism and the tibial plateau. Patellar fractures have been documented as occurring in 0.2% to 2.3% of cases.^5-7 One paper reported a fracture in 1.3% of cases at a mean of 57 days, with roughly half caused by trauma and the other half having atraumatic causes.⁸ Lee and colleagues⁹ found a 0.2% complication rate for all BPTB grafts in 1725 consecutive patients. Although some patients were treated nonoperatively, others underwent operative fixation. Time to clinical and radiographic healing was 7 and 10 weeks, respectively.

Tibial plateau fracture after BPTB harvest is a rare complication, with 11 cases reported in the literature.¹⁰ In 4 of those cases, the proposed mechanism of fracture was a stress riser resulting from the synergistic weakness of the tibial harvest site combined with the tibial tunnel reducing proximal tibial bone strength.^11-14 The mechanism of injury varied from traumatic to insufficiency fracture, with fixation varying with fracture displacement.

Tibial tubercle fracture after BPTB harvest is extremely rare, with the present case being only the third published in the literature. Like most reported post-ACL reconstruction extensor mechanism disruptions, our case resulted from a traumatic event at an interval after surgery. All other tibial tubercle fracture post-ACL reconstruction disruptions occurred within 2 weeks after surgery.^1,2 Sudden tension on the extensor mechanism secondary to hyperflexion caused a fracture through a weakened tibial tubercle with avulsion of the remaining tendon in 2 of the 3 cases, with the third being a lower stress popping noise that occurred during a pivot to stand.¹

The residual defect after tibial bone block harvest could represent a weakening of the tubercle by loss of structural bone and by development of stress risers. The previous reports of tibial tubercle fracture after BPTB harvest documented a similar methodology: Use a bone saw and osteotomes to harvest a trapezoidal tibial bone plug 10 mm to 11 mm wide and 22 cm to 35 cm long. As previously documented, we suggest taking care with saw cuts and osteotomes so as not to weaken the proximal tibia or distal patella more than is necessary.^1,2 Before surgery, patients should be warned about the possibility of extensor mechanism injuries with use of BPTB grafts.

Conclusion

Tibial tubercle fracture after BPTB harvest for ACL reconstruction is an extremely rare complication. Treatment is ORIF of the tubercle fragment, with a delay in ACL rehabilitation in cases involving the ipsilateral knee.

Am J Orthop. 2016;45(7):E469-E471. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Leg-length discrepancy (LLD) is common in the general population¹ and particularly in patients with degenerative joint diseases of the hip and knee.² Common complications of LLD include femoral, sciatic, and peroneal nerve palsy; lower back pain; gait abnormalities³; and general dissatisfaction. LLD is a concern for orthopedic surgeons who perform total knee arthroplasty (TKA) because limb lengthening is common after this procedure.^4,5 Surgeons are aware of the limb lengthening that occurs during TKA,^4,5 and studies have confirmed that LLD usually decreases after TKA.^4,5

Despite surgeons’ best efforts, some patients still perceive LLD after surgery, though the incidence of perceived LLD in patients who have had TKA has not been well documented. Aside from actual, objectively measured LLD, there may be other factors that lead patients to perceive LLD. Study results have suggested that preoperative varus–valgus alignment of the knee joint may correlate with how much an operative leg is lengthened after TKA^4,5; however, the outcome investigated was objective LLD measurements, not perceived LLD. Understanding the factors that may influence patients’ ability to perceive LLD would allow surgeons to preoperatively identify patients who are at higher risk for postoperative perceived LLD. This information, along with expected time to resolution of postoperative perceived LLD, would allow surgeons to educate their patients accordingly.

We conducted a study to determine the incidence of perceived LLD before and after primary TKA in patients with unilateral osteoarthritis and to determine the correlation between mechanical axis of the knee and perceived LLD before and after surgery. Given that surgery may correct mechanical axis misalignment, we investigated the correlation between this correction and its ability to change patients’ preoperative and postoperative perceived LLD. We hypothesized that a large correction of mechanical axis would lead patients to perceive LLD after surgery. The relationship of body mass index (BMI) and age to patients’ perceived LLD was also assessed. The incidence and time frame of resolution of postoperative perceived LLD were determined.

Methods

Approval for this study was received from the Institutional Review Board at our institution, Rush University Medical Center in Chicago, Illinois. Seventy-three patients undergoing primary TKA performed by 3 surgeons at 2 institutions between February 2010 and January 2013 were prospectively enrolled. Inclusion criteria were age 18 years to 90 years and primary TKA for unilateral osteoarthritis; exclusion criteria were allergy or intolerance to the study materials, operative treatment of affected joint or its underlying etiology within prior month, previous surgeries (other than arthroscopy) on affected joint, previous surgeries (on unaffected lower extremity) that may influence preoperative and postoperative leg lengths, and any substance abuse or dependence within the past 6 months. Patients provided written informed consent for total knee arthroplasty.

All surgeries were performed by Dr. Levine, Dr. Della Valle, and Dr. Sporer using the medial parapatellar or midvastus approach with tourniquet. Similar standard postoperative rehabilitation protocols with early mobilization were used in all cases.

During clinical evaluation, patient demographic data were collected and LLD surveys administered. Patients were asked, before surgery and 3 to 6 weeks, 3 months, 6 months, and 1 year after surgery, if they perceived LLD. A patient who no longer perceived LLD after surgery was no longer followed for this study.

At the preoperative clinic visit and at the 3-month or 6-week postoperative visit, standing mechanical axis radiographs were viewed by 2 of the authors (not the primary surgeons) using PACS (picture archiving and communication system software). The mechanical axis of the operative leg was measured with ImageJ software by taking the angle from the center of the femur to the middle of the ankle joint, with the vertex assigned to the middle of the knee joint.

We used a 2-tailed unpaired t test to determine the relationship of preoperative mechanical axis to perceived LLD (or lack thereof) before surgery. The data were analyzed for separate varus and valgus deformities. Then we determined the relationship of postoperative mechanical axis to perceived LLD (or lack thereof) after surgery. The McNemar test was used to determine the effect of surgery on patients’ LLD perceptions.

To determine the relationship between preoperative-to-postoperative change in mechanical axis and change in LLD perceptions, we divided patients into 4 groups. Group 1 had both preoperative and postoperative perceived LLD, group 2 had no preoperative or postoperative perceived LLD, group 3 had preoperative perceived LLD but no postoperative perceived LLD, and group 4 had postoperative perceived LLD but no preoperative perceived LLD. The absolute value of the difference between preoperative and postoperative mechanical axis was then determined, relative to 180°, to account for changes in varus to valgus deformity before and after surgery and vice versa. Analysis of variance (ANOVA) was used to detect differences between groups. This analysis was then stratified based on BMI and age.

Results

Of the 73 enrolled patients, 2 were excluded from results analysis because of inadequate data—one did not complete the postoperative LLD survey, and the other did not have postoperative standing mechanical axis radiographs—leaving 71 patients (27 men, 44 women) with adequate data. Mean (SD) age of all patients was 65 (8.4) years (range, 47-89 years). Mean (SD) BMI was 35.1 (9.9; range, 20.2-74.8).

Of the 71 patients with adequate data, 18 had preoperative perceived LLD and 53 did not; in addition, 7 had postoperative perceived LLD and 64 did not. All 7 patients with postoperative perceived LLD noted resolution of LLD, at a mean of 8.5 weeks (range, 3 weeks-3 months). There was a significant difference between the 18 patients with preoperative perceived LLD and the 7 with postoperative perceived LLD (P = .035, analyzed with the McNemar test).

Table 1 lists the mean preoperative mechanical axis measurements for patients with and without preoperative perceived LLD.

Discussion

In this study, 18 patients (25%) had preoperative perceived LLD, proving that perceived LLD is common in patients who undergo TKA for unilateral osteoarthritis. Surgeons should give their patients a preoperative survey on perceived LLD, as survey responses may inform and influence surgical decisions and strategies.

Of the 18 patients with preoperative perceived LLD, only 1 had postoperative perceived LLD. That perceived LLD decreased after surgery makes sense given the widely accepted notion that actual LLD is common before primary TKA but in most cases is corrected during surgery.^4,5 As LLD correction during surgery is so successful, surgeons should tell their patients with preoperative perceived LLD that in most cases it will be fixed after TKA.

Although the incidence of perceived LLD decreased after TKA (as mentioned earlier), the decrease seemed to be restricted mostly to patients with preoperative perceived LLD, and the underlying LLD was most probably corrected by the surgery. However, surgery introduced perceived LLD in 6 cases, supporting the notion that it is crucial to understand which patients are at higher risk for postoperative perceived LLD and what if any time frame can be expected for resolution in these cases. In our study, all cases of perceived LLD had resolved by a mean follow-up of 8.5 weeks (range, 3 weeks-3 months). This phenomenon of resolution may be attributed to some of the physical, objective LLD corrections that naturally occur throughout the postoperative course,⁴ though psychological factors may also be involved. Our study results suggest patients should be counseled that, though about 10% of patients perceive LLD after primary TKA, the vast majority of perceived LLD cases resolve within 3 months.

One study goal was to determine the relationship between the mechanical axis of the knee and perceived LLD both before and after surgery. There were no significant relationships. This was also true when cases of varus and valgus deformity were analyzed separately.

Another study goal was to determine if a surgical change in the mechanical alignment of the knee would influence preoperative-to-postoperative LLD perceptions. In our analysis, patients were divided into 4 groups based on their preoperative and postoperative LLD perceptions (see Methods section). ANOVA revealed no significant differences in absolute values of mechanical axis correction among the 4 groups. Likewise, there were no correlations between BMI and age and mechanical axis correction among the groups, suggesting LLD perception is unrelated to any of these variables. Ideally, if a relationship between a threshold knee alignment value and perceived LLD existed, surgeons would be able to counsel patients at higher risk for perceived LLD about how their knee alignment may contribute to their perception. Unfortunately, our study results did not show any significant statistical relationships in this regard.

The problem of LLD in patients undergoing TKA is not new, and much research is needed to determine the correlation between perceived versus actual discrepancies, and why they occur. Our study results confirmed that TKA corrects most cases of preoperative perceived LLD but introduces perceived LLD in other cases. Whether preoperative or postoperative LLD is merely perceived or is in fact an actual discrepancy remains to be seen.

One limitation of this study was its lack of leg-length measurements. Although we studied knee alignment specifically, it would have been useful to compare perceived LLD with measured leg lengths, either clinically or radiographically, especially since leg lengths obviously play a role in any perceived LLD. We used mechanical alignment as a surrogate for actual LLD because we hypothesized that alignment may contribute to patients’ perceived discrepancies.

Another limitation was the relatively small sample. Only 24 cases of perceived LLD were analyzed. Given our low rates of perceived LLD (25% before surgery, 10% after surgery), it is difficult to study a large enough TKA group to establish a statistically significant number of cases. Nevertheless, investigators may use larger groups to establish more meaningful relationships.

A third limitation was that alignment was measured on the operative side but not the contralateral side. As we were focusing on perceived discrepancy, contralateral knee alignment may play an important role. Our study involved patients with unilateral osteoarthritis, so it would be reasonable to assume the nonoperative knee was almost neutral in alignment in most cases. However, given that varus/valgus misalignment is a known risk factor for osteoarthritis,⁶ many of our patients with unilateral disease may very well have had preexisting misalignment of both knees. The undetermined alignment of the nonoperative side may be a confounding variable in the relationship between operative knee alignment and perceived LLD.

Fourth, not all patients were surveyed 3 weeks after surgery. Some were first surveyed at 6 weeks, and it is possible there were cases of transient postoperative LLD that resolved before that point. Therefore, our reported incidence of postoperative LLD could have missed some cases. In addition, our mean 8.5-week period for LLD resolution may not have accounted for these resolved cases of transient perceived LLD.

Am J Orthop. 2016;45(7):E429-E433. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Leg-length discrepancy (LLD) is common in the general population¹ and particularly in patients with degenerative joint diseases of the hip and knee.² Common complications of LLD include femoral, sciatic, and peroneal nerve palsy; lower back pain; gait abnormalities³; and general dissatisfaction. LLD is a concern for orthopedic surgeons who perform total knee arthroplasty (TKA) because limb lengthening is common after this procedure.^4,5 Surgeons are aware of the limb lengthening that occurs during TKA,^4,5 and studies have confirmed that LLD usually decreases after TKA.^4,5

Despite surgeons’ best efforts, some patients still perceive LLD after surgery, though the incidence of perceived LLD in patients who have had TKA has not been well documented. Aside from actual, objectively measured LLD, there may be other factors that lead patients to perceive LLD. Study results have suggested that preoperative varus–valgus alignment of the knee joint may correlate with how much an operative leg is lengthened after TKA^4,5; however, the outcome investigated was objective LLD measurements, not perceived LLD. Understanding the factors that may influence patients’ ability to perceive LLD would allow surgeons to preoperatively identify patients who are at higher risk for postoperative perceived LLD. This information, along with expected time to resolution of postoperative perceived LLD, would allow surgeons to educate their patients accordingly.

We conducted a study to determine the incidence of perceived LLD before and after primary TKA in patients with unilateral osteoarthritis and to determine the correlation between mechanical axis of the knee and perceived LLD before and after surgery. Given that surgery may correct mechanical axis misalignment, we investigated the correlation between this correction and its ability to change patients’ preoperative and postoperative perceived LLD. We hypothesized that a large correction of mechanical axis would lead patients to perceive LLD after surgery. The relationship of body mass index (BMI) and age to patients’ perceived LLD was also assessed. The incidence and time frame of resolution of postoperative perceived LLD were determined.

Methods

Approval for this study was received from the Institutional Review Board at our institution, Rush University Medical Center in Chicago, Illinois. Seventy-three patients undergoing primary TKA performed by 3 surgeons at 2 institutions between February 2010 and January 2013 were prospectively enrolled. Inclusion criteria were age 18 years to 90 years and primary TKA for unilateral osteoarthritis; exclusion criteria were allergy or intolerance to the study materials, operative treatment of affected joint or its underlying etiology within prior month, previous surgeries (other than arthroscopy) on affected joint, previous surgeries (on unaffected lower extremity) that may influence preoperative and postoperative leg lengths, and any substance abuse or dependence within the past 6 months. Patients provided written informed consent for total knee arthroplasty.

All surgeries were performed by Dr. Levine, Dr. Della Valle, and Dr. Sporer using the medial parapatellar or midvastus approach with tourniquet. Similar standard postoperative rehabilitation protocols with early mobilization were used in all cases.

During clinical evaluation, patient demographic data were collected and LLD surveys administered. Patients were asked, before surgery and 3 to 6 weeks, 3 months, 6 months, and 1 year after surgery, if they perceived LLD. A patient who no longer perceived LLD after surgery was no longer followed for this study.

At the preoperative clinic visit and at the 3-month or 6-week postoperative visit, standing mechanical axis radiographs were viewed by 2 of the authors (not the primary surgeons) using PACS (picture archiving and communication system software). The mechanical axis of the operative leg was measured with ImageJ software by taking the angle from the center of the femur to the middle of the ankle joint, with the vertex assigned to the middle of the knee joint.

We used a 2-tailed unpaired t test to determine the relationship of preoperative mechanical axis to perceived LLD (or lack thereof) before surgery. The data were analyzed for separate varus and valgus deformities. Then we determined the relationship of postoperative mechanical axis to perceived LLD (or lack thereof) after surgery. The McNemar test was used to determine the effect of surgery on patients’ LLD perceptions.

To determine the relationship between preoperative-to-postoperative change in mechanical axis and change in LLD perceptions, we divided patients into 4 groups. Group 1 had both preoperative and postoperative perceived LLD, group 2 had no preoperative or postoperative perceived LLD, group 3 had preoperative perceived LLD but no postoperative perceived LLD, and group 4 had postoperative perceived LLD but no preoperative perceived LLD. The absolute value of the difference between preoperative and postoperative mechanical axis was then determined, relative to 180°, to account for changes in varus to valgus deformity before and after surgery and vice versa. Analysis of variance (ANOVA) was used to detect differences between groups. This analysis was then stratified based on BMI and age.

Results

Of the 73 enrolled patients, 2 were excluded from results analysis because of inadequate data—one did not complete the postoperative LLD survey, and the other did not have postoperative standing mechanical axis radiographs—leaving 71 patients (27 men, 44 women) with adequate data. Mean (SD) age of all patients was 65 (8.4) years (range, 47-89 years). Mean (SD) BMI was 35.1 (9.9; range, 20.2-74.8).

Of the 71 patients with adequate data, 18 had preoperative perceived LLD and 53 did not; in addition, 7 had postoperative perceived LLD and 64 did not. All 7 patients with postoperative perceived LLD noted resolution of LLD, at a mean of 8.5 weeks (range, 3 weeks-3 months). There was a significant difference between the 18 patients with preoperative perceived LLD and the 7 with postoperative perceived LLD (P = .035, analyzed with the McNemar test).

Table 1 lists the mean preoperative mechanical axis measurements for patients with and without preoperative perceived LLD.

Discussion

In this study, 18 patients (25%) had preoperative perceived LLD, proving that perceived LLD is common in patients who undergo TKA for unilateral osteoarthritis. Surgeons should give their patients a preoperative survey on perceived LLD, as survey responses may inform and influence surgical decisions and strategies.

Of the 18 patients with preoperative perceived LLD, only 1 had postoperative perceived LLD. That perceived LLD decreased after surgery makes sense given the widely accepted notion that actual LLD is common before primary TKA but in most cases is corrected during surgery.^4,5 As LLD correction during surgery is so successful, surgeons should tell their patients with preoperative perceived LLD that in most cases it will be fixed after TKA.

Although the incidence of perceived LLD decreased after TKA (as mentioned earlier), the decrease seemed to be restricted mostly to patients with preoperative perceived LLD, and the underlying LLD was most probably corrected by the surgery. However, surgery introduced perceived LLD in 6 cases, supporting the notion that it is crucial to understand which patients are at higher risk for postoperative perceived LLD and what if any time frame can be expected for resolution in these cases. In our study, all cases of perceived LLD had resolved by a mean follow-up of 8.5 weeks (range, 3 weeks-3 months). This phenomenon of resolution may be attributed to some of the physical, objective LLD corrections that naturally occur throughout the postoperative course,⁴ though psychological factors may also be involved. Our study results suggest patients should be counseled that, though about 10% of patients perceive LLD after primary TKA, the vast majority of perceived LLD cases resolve within 3 months.

One study goal was to determine the relationship between the mechanical axis of the knee and perceived LLD both before and after surgery. There were no significant relationships. This was also true when cases of varus and valgus deformity were analyzed separately.

Another study goal was to determine if a surgical change in the mechanical alignment of the knee would influence preoperative-to-postoperative LLD perceptions. In our analysis, patients were divided into 4 groups based on their preoperative and postoperative LLD perceptions (see Methods section). ANOVA revealed no significant differences in absolute values of mechanical axis correction among the 4 groups. Likewise, there were no correlations between BMI and age and mechanical axis correction among the groups, suggesting LLD perception is unrelated to any of these variables. Ideally, if a relationship between a threshold knee alignment value and perceived LLD existed, surgeons would be able to counsel patients at higher risk for perceived LLD about how their knee alignment may contribute to their perception. Unfortunately, our study results did not show any significant statistical relationships in this regard.

The problem of LLD in patients undergoing TKA is not new, and much research is needed to determine the correlation between perceived versus actual discrepancies, and why they occur. Our study results confirmed that TKA corrects most cases of preoperative perceived LLD but introduces perceived LLD in other cases. Whether preoperative or postoperative LLD is merely perceived or is in fact an actual discrepancy remains to be seen.

One limitation of this study was its lack of leg-length measurements. Although we studied knee alignment specifically, it would have been useful to compare perceived LLD with measured leg lengths, either clinically or radiographically, especially since leg lengths obviously play a role in any perceived LLD. We used mechanical alignment as a surrogate for actual LLD because we hypothesized that alignment may contribute to patients’ perceived discrepancies.

Another limitation was the relatively small sample. Only 24 cases of perceived LLD were analyzed. Given our low rates of perceived LLD (25% before surgery, 10% after surgery), it is difficult to study a large enough TKA group to establish a statistically significant number of cases. Nevertheless, investigators may use larger groups to establish more meaningful relationships.

A third limitation was that alignment was measured on the operative side but not the contralateral side. As we were focusing on perceived discrepancy, contralateral knee alignment may play an important role. Our study involved patients with unilateral osteoarthritis, so it would be reasonable to assume the nonoperative knee was almost neutral in alignment in most cases. However, given that varus/valgus misalignment is a known risk factor for osteoarthritis,⁶ many of our patients with unilateral disease may very well have had preexisting misalignment of both knees. The undetermined alignment of the nonoperative side may be a confounding variable in the relationship between operative knee alignment and perceived LLD.

Fourth, not all patients were surveyed 3 weeks after surgery. Some were first surveyed at 6 weeks, and it is possible there were cases of transient postoperative LLD that resolved before that point. Therefore, our reported incidence of postoperative LLD could have missed some cases. In addition, our mean 8.5-week period for LLD resolution may not have accounted for these resolved cases of transient perceived LLD.

Am J Orthop. 2016;45(7):E429-E433. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Leg-length discrepancy (LLD) is common in the general population¹ and particularly in patients with degenerative joint diseases of the hip and knee.² Common complications of LLD include femoral, sciatic, and peroneal nerve palsy; lower back pain; gait abnormalities³; and general dissatisfaction. LLD is a concern for orthopedic surgeons who perform total knee arthroplasty (TKA) because limb lengthening is common after this procedure.^4,5 Surgeons are aware of the limb lengthening that occurs during TKA,^4,5 and studies have confirmed that LLD usually decreases after TKA.^4,5

Despite surgeons’ best efforts, some patients still perceive LLD after surgery, though the incidence of perceived LLD in patients who have had TKA has not been well documented. Aside from actual, objectively measured LLD, there may be other factors that lead patients to perceive LLD. Study results have suggested that preoperative varus–valgus alignment of the knee joint may correlate with how much an operative leg is lengthened after TKA^4,5; however, the outcome investigated was objective LLD measurements, not perceived LLD. Understanding the factors that may influence patients’ ability to perceive LLD would allow surgeons to preoperatively identify patients who are at higher risk for postoperative perceived LLD. This information, along with expected time to resolution of postoperative perceived LLD, would allow surgeons to educate their patients accordingly.

We conducted a study to determine the incidence of perceived LLD before and after primary TKA in patients with unilateral osteoarthritis and to determine the correlation between mechanical axis of the knee and perceived LLD before and after surgery. Given that surgery may correct mechanical axis misalignment, we investigated the correlation between this correction and its ability to change patients’ preoperative and postoperative perceived LLD. We hypothesized that a large correction of mechanical axis would lead patients to perceive LLD after surgery. The relationship of body mass index (BMI) and age to patients’ perceived LLD was also assessed. The incidence and time frame of resolution of postoperative perceived LLD were determined.

Methods

Approval for this study was received from the Institutional Review Board at our institution, Rush University Medical Center in Chicago, Illinois. Seventy-three patients undergoing primary TKA performed by 3 surgeons at 2 institutions between February 2010 and January 2013 were prospectively enrolled. Inclusion criteria were age 18 years to 90 years and primary TKA for unilateral osteoarthritis; exclusion criteria were allergy or intolerance to the study materials, operative treatment of affected joint or its underlying etiology within prior month, previous surgeries (other than arthroscopy) on affected joint, previous surgeries (on unaffected lower extremity) that may influence preoperative and postoperative leg lengths, and any substance abuse or dependence within the past 6 months. Patients provided written informed consent for total knee arthroplasty.

All surgeries were performed by Dr. Levine, Dr. Della Valle, and Dr. Sporer using the medial parapatellar or midvastus approach with tourniquet. Similar standard postoperative rehabilitation protocols with early mobilization were used in all cases.

During clinical evaluation, patient demographic data were collected and LLD surveys administered. Patients were asked, before surgery and 3 to 6 weeks, 3 months, 6 months, and 1 year after surgery, if they perceived LLD. A patient who no longer perceived LLD after surgery was no longer followed for this study.

At the preoperative clinic visit and at the 3-month or 6-week postoperative visit, standing mechanical axis radiographs were viewed by 2 of the authors (not the primary surgeons) using PACS (picture archiving and communication system software). The mechanical axis of the operative leg was measured with ImageJ software by taking the angle from the center of the femur to the middle of the ankle joint, with the vertex assigned to the middle of the knee joint.

We used a 2-tailed unpaired t test to determine the relationship of preoperative mechanical axis to perceived LLD (or lack thereof) before surgery. The data were analyzed for separate varus and valgus deformities. Then we determined the relationship of postoperative mechanical axis to perceived LLD (or lack thereof) after surgery. The McNemar test was used to determine the effect of surgery on patients’ LLD perceptions.

To determine the relationship between preoperative-to-postoperative change in mechanical axis and change in LLD perceptions, we divided patients into 4 groups. Group 1 had both preoperative and postoperative perceived LLD, group 2 had no preoperative or postoperative perceived LLD, group 3 had preoperative perceived LLD but no postoperative perceived LLD, and group 4 had postoperative perceived LLD but no preoperative perceived LLD. The absolute value of the difference between preoperative and postoperative mechanical axis was then determined, relative to 180°, to account for changes in varus to valgus deformity before and after surgery and vice versa. Analysis of variance (ANOVA) was used to detect differences between groups. This analysis was then stratified based on BMI and age.

Results

Of the 73 enrolled patients, 2 were excluded from results analysis because of inadequate data—one did not complete the postoperative LLD survey, and the other did not have postoperative standing mechanical axis radiographs—leaving 71 patients (27 men, 44 women) with adequate data. Mean (SD) age of all patients was 65 (8.4) years (range, 47-89 years). Mean (SD) BMI was 35.1 (9.9; range, 20.2-74.8).

Of the 71 patients with adequate data, 18 had preoperative perceived LLD and 53 did not; in addition, 7 had postoperative perceived LLD and 64 did not. All 7 patients with postoperative perceived LLD noted resolution of LLD, at a mean of 8.5 weeks (range, 3 weeks-3 months). There was a significant difference between the 18 patients with preoperative perceived LLD and the 7 with postoperative perceived LLD (P = .035, analyzed with the McNemar test).

Table 1 lists the mean preoperative mechanical axis measurements for patients with and without preoperative perceived LLD.

Discussion

In this study, 18 patients (25%) had preoperative perceived LLD, proving that perceived LLD is common in patients who undergo TKA for unilateral osteoarthritis. Surgeons should give their patients a preoperative survey on perceived LLD, as survey responses may inform and influence surgical decisions and strategies.

Of the 18 patients with preoperative perceived LLD, only 1 had postoperative perceived LLD. That perceived LLD decreased after surgery makes sense given the widely accepted notion that actual LLD is common before primary TKA but in most cases is corrected during surgery.^4,5 As LLD correction during surgery is so successful, surgeons should tell their patients with preoperative perceived LLD that in most cases it will be fixed after TKA.

Although the incidence of perceived LLD decreased after TKA (as mentioned earlier), the decrease seemed to be restricted mostly to patients with preoperative perceived LLD, and the underlying LLD was most probably corrected by the surgery. However, surgery introduced perceived LLD in 6 cases, supporting the notion that it is crucial to understand which patients are at higher risk for postoperative perceived LLD and what if any time frame can be expected for resolution in these cases. In our study, all cases of perceived LLD had resolved by a mean follow-up of 8.5 weeks (range, 3 weeks-3 months). This phenomenon of resolution may be attributed to some of the physical, objective LLD corrections that naturally occur throughout the postoperative course,⁴ though psychological factors may also be involved. Our study results suggest patients should be counseled that, though about 10% of patients perceive LLD after primary TKA, the vast majority of perceived LLD cases resolve within 3 months.

One study goal was to determine the relationship between the mechanical axis of the knee and perceived LLD both before and after surgery. There were no significant relationships. This was also true when cases of varus and valgus deformity were analyzed separately.

Another study goal was to determine if a surgical change in the mechanical alignment of the knee would influence preoperative-to-postoperative LLD perceptions. In our analysis, patients were divided into 4 groups based on their preoperative and postoperative LLD perceptions (see Methods section). ANOVA revealed no significant differences in absolute values of mechanical axis correction among the 4 groups. Likewise, there were no correlations between BMI and age and mechanical axis correction among the groups, suggesting LLD perception is unrelated to any of these variables. Ideally, if a relationship between a threshold knee alignment value and perceived LLD existed, surgeons would be able to counsel patients at higher risk for perceived LLD about how their knee alignment may contribute to their perception. Unfortunately, our study results did not show any significant statistical relationships in this regard.

The problem of LLD in patients undergoing TKA is not new, and much research is needed to determine the correlation between perceived versus actual discrepancies, and why they occur. Our study results confirmed that TKA corrects most cases of preoperative perceived LLD but introduces perceived LLD in other cases. Whether preoperative or postoperative LLD is merely perceived or is in fact an actual discrepancy remains to be seen.

One limitation of this study was its lack of leg-length measurements. Although we studied knee alignment specifically, it would have been useful to compare perceived LLD with measured leg lengths, either clinically or radiographically, especially since leg lengths obviously play a role in any perceived LLD. We used mechanical alignment as a surrogate for actual LLD because we hypothesized that alignment may contribute to patients’ perceived discrepancies.

Another limitation was the relatively small sample. Only 24 cases of perceived LLD were analyzed. Given our low rates of perceived LLD (25% before surgery, 10% after surgery), it is difficult to study a large enough TKA group to establish a statistically significant number of cases. Nevertheless, investigators may use larger groups to establish more meaningful relationships.

A third limitation was that alignment was measured on the operative side but not the contralateral side. As we were focusing on perceived discrepancy, contralateral knee alignment may play an important role. Our study involved patients with unilateral osteoarthritis, so it would be reasonable to assume the nonoperative knee was almost neutral in alignment in most cases. However, given that varus/valgus misalignment is a known risk factor for osteoarthritis,⁶ many of our patients with unilateral disease may very well have had preexisting misalignment of both knees. The undetermined alignment of the nonoperative side may be a confounding variable in the relationship between operative knee alignment and perceived LLD.

Fourth, not all patients were surveyed 3 weeks after surgery. Some were first surveyed at 6 weeks, and it is possible there were cases of transient postoperative LLD that resolved before that point. Therefore, our reported incidence of postoperative LLD could have missed some cases. In addition, our mean 8.5-week period for LLD resolution may not have accounted for these resolved cases of transient perceived LLD.

Am J Orthop. 2016;45(7):E429-E433. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Risk factors for dislocation after reverse total shoulder arthroplasty (RTSA) are not clearly defined. Prosthetic dislocation can result in poor patient satisfaction, worse functional outcomes, and return to the operating room.^1-3 As a result, identification of modifiable risk factors for complications represents an important research initiative for shoulder surgeons.

There is a paucity of literature devoted to the study of dislocation after RTSA. Chalmers and colleagues⁴ found a 2.9% (11/385) incidence of early dislocation within 3 months after index surgery—an improvement over the 15.8% reported for early instability over the period 2004–2006.⁵ As prosthesis design has improved and surgeons have become more comfortable with the RTSA prosthesis, surgical indications have expanded,^6,7 and dislocation rates appear to have decreased. Although the most common indication for RTSA continues to be cuff tear arthropathy (CTA),⁶ there has been increased use in rheumatoid arthritis^8-10; proximal humerus fractures, especially in cases of poor bone quality and unreliable fixation of tuberosities^11-13; and failed previous shoulder reconstruction.^14,15 As RTSA is performed more often, limiting the complications will become more important for both patient care and economics.

We conducted a study to analyze dislocation rates at our institution and to identify both modifiable and nonmodifiable risk factors for dislocation after RTSA. By identifying risk factors for dislocation, we will be able to implement additional perioperative clinical measures to reduce the incidence of dislocation.

Materials and Methods

This retrospective study of dislocation after RTSA was conducted at the Rothman Institute of Orthopedics and Methodist Hospital (Thomas Jefferson University Hospitals, Philadelphia, PA). After obtaining Institutional Review Board approval for the study, we searched our institution’s electronic database of shoulder arthroplasties to identify all RTSAs performed at our 2 large-volume urban institutions between September 27, 2010 and December 31, 2013. For the record search, International Classification of Diseases, Ninth Revision (ICD-9) codes were used (Table 1).

The medical records of each patient were used to identify independent variables that could be associated with dislocation rate. Demographic variables included sex, age, and race. Preoperative clinical data included body mass index (BMI), etiology of shoulder disease leading to RTSA, individual comorbidities, and Charlson Comorbidity Index (CCI)¹⁶ modified to be used with ICD-9 codes.¹⁷ In addition, prior shoulder surgery history and arthroplasty type (primary or revision) were determined. Postoperative considerations were time to dislocation, mechanism of dislocation, and intervention(s) needed for dislocation. Although the institutional database did not include operative variables such as prosthesis type and surgical approach, all 6 surgeons in this study were using a standard deltopectoral approach in beach-chair position with a Grammont style prosthesis for RTSA cases.

Descriptive statistics for RTSA patients and the dislocation subpopulation were compiled. Bivariate analysis was used to evaluate which of the previously described variables influenced dislocation rates. Last, multivariate logistic regression analysis was performed to evaluate which factors were independent predictors of dislocation. We included demographic variables (age, sex, ethnicity), clinical variables (BMI, individual comorbidities, CCI), and surgical variables (primary vs revision, diagnosis at time of surgery). All statistical analyses were performed with Excel 2013 (Microsoft) and SPSS Statistics Version 20.0 (SPSS Inc.).

Results

From the database, we identified 487 patients who underwent 510 RTSAs during the study period. These surgeries were performed by 6 shoulder and elbow fellowship–trained surgeons. Of the 510 RTSAs, 393 (77.1%) were primary cases, and 117 (22.9%) were revision cases.

Of the 510 shoulders that underwent RTSA, 15 (2.9%; 14 patients) dislocated. Of these 15 cases, 5 were primary (1.3% of all primary cases) and 10 were revision (8.5% of all revision cases). Mean time from index surgery to diagnosis of dislocation was 58.2 days (range, 0-319 days). One dislocation occurred immediately after surgery, 2 after falls, 4 from patient-identified low-energy mechanisms of injury, and 8 without known inciting events. Nine dislocations (60%) did not have a subscapularis repair (7 were irreparable, 2 underwent subscapularis peel without repair), and the other 6 were repaired primarily (Table 2).

Discussion

With more RTSAs being performed, evaluation of their common complications becomes increasingly important.¹⁸ We found a 3.0% rate of dislocation after RTSA, which is consistent with the most recently reported incidence⁴ and falls within the previously described range of 0% to 8.6%.^19-26 Of the clinical risk factors identified in this study, those previously described were prior surgery, subscapularis insufficiency, higher BMI, and male sex.⁴ However, our finding of lower risk of dislocation after RTSA for primary rotator cuff pathology was not previously described. Although Chalmers and colleagues⁴ did not report this lower risk, 3 (27.3%) of their 11 patients with dislocation had primary CTA, compared with 1 (6.7%) of 15 patients in the present study.⁴ Our literature review did not identify any studies that independently reported the dislocation rate in patients who underwent RTSA for rotator cuff failure.

The risk factors of subscapularis irreparability and revision surgery suggest the importance of the soft-tissue envelope and bony anatomy in dislocation prevention. Previous analyses have suggested implant malpositioning,^27,28 poor subscapularis quality,²⁹ and inadequate muscle tensioning^5,30-32 as risk factors for RTSA. Patients with an irreparable subscapularis tendon have often had multiple surgeries with compromise to the muscle/soft-tissue envelope or bony anatomy of the shoulder. A biomechanical study by Gutiérrez and colleagues³¹ found the compressive forces of the soft tissue at the glenohumeral joint to be the most important contributor to stability in the RTSA prosthesis. In clinical studies, the role of the subscapularis in preventing instability after RTSA remains unclear. Edwards and colleagues²⁹ prospectively compared dislocation rates in patients with reparable and irreparable subscapularis tendons during RTSA and found a higher rate of dislocation in the irreparable subscapularis group. Of note, patients in the irreparable subscapularis group also had more complex diagnoses, including proximal humeral nonunion, fixed glenohumeral dislocation, and failed prior arthroplasty. Clark and colleagues³³ retrospectively analyzed subscapularis repair in 2 RTSA groups and found no appreciable effect on complication rate, dislocation events, range-of-motion gains, or pain relief.

Our finding that higher BMI is an independent risk factor was previously described.⁴ The association is unclear but could be related to implant positioning, difficulty in intraoperative assessment of muscle tensioning, or body habitus that may generate a lever arm for impingement and dislocation when the arm is in adduction. Last, our finding that male sex is a risk factor for dislocation approached significance, and this relationship was previously reported.⁴ This could be attributable to a higher rate of activity or of indolent infection in male patients.^34,35Besides studying risk factors for dislocation after RTSA, we investigated treatment. None of our patients were treated successfully and definitively with closed reduction in the clinic. This finding diverges from findings in studies by Teusink and colleagues² and Chalmers and colleagues,⁴who respectively reported 62% and 44% rates of success with closed reduction. Our cohort of 14 patients with 15 dislocations required a total of 17 trips to the operating room after dislocation. This significantly higher rate of return to the operating room suggests that dislocation after RTSA may be a more costly and morbid problem than has been previously described.

This study had several weaknesses. Despite its large consecutive series of patients, the study was retrospective, and several variables that would be documented and controlled in a prospective study could not be measured here. Specifically, neither preoperative physical examination nor patient-specific assessments of pain or function were consistently obtained. Similarly, postoperative patient-specific instruments of outcomes evaluation were not obtained consistently, so results of patients with dislocation could not be compared with those of a control group. In addition, preoperative and postoperative radiographs were not consistently present in our electronic medical records, so the influence of preoperative bony anatomy, intraoperative limb lengthening, and any implant malpositioning could not be determined. Furthermore, operative details, such as reparability of the subscapularis, were not fully available for the control group and could not be included in statistical analysis. In addition, that the known dislocation risk factor of male sex⁴ was identified here but was not significant in multivariate regression analysis suggests that this study may not have been adequately powered to identify a significant difference in dislocation rate between the sexes. Last, though our results suggested associations between the aforementioned variables and dislocation after RTSA, a truly causative relationship could not be confirmed with this study design or analysis. Therefore, our study findings are hypothesis-generating and may indicate a benefit to greater deltoid tensioning, use of retentive liners, or more conservative rehabilitation protocols for high-risk patients.

Conclusion

Dislocation after RTSA is an uncommon complication that often requires a return to the operating room. This study identified a modifiable risk factor (higher BMI) and 3 nonmodifiable risk factors (male sex, subscapularis insufficiency, revision surgery) for dislocation after RTSA. In contrast, patients who undergo RTSA for primary rotator cuff pathology are unlikely to dislocate after surgery. This low risk of dislocation after RTSA for primary cuff pathology was not previously described. Patients in the higher risk category may benefit from preoperative lifestyle modification, intraoperative techniques for increasing stability, and more conservative therapy after surgery. In addition, unlike previous investigations, this study did not find closed reduction in the clinic alone to be successful in definitively treating this patient population.

Am J Orthop. 2016;45(7):E444-E450. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Risk factors for dislocation after reverse total shoulder arthroplasty (RTSA) are not clearly defined. Prosthetic dislocation can result in poor patient satisfaction, worse functional outcomes, and return to the operating room.^1-3 As a result, identification of modifiable risk factors for complications represents an important research initiative for shoulder surgeons.

There is a paucity of literature devoted to the study of dislocation after RTSA. Chalmers and colleagues⁴ found a 2.9% (11/385) incidence of early dislocation within 3 months after index surgery—an improvement over the 15.8% reported for early instability over the period 2004–2006.⁵ As prosthesis design has improved and surgeons have become more comfortable with the RTSA prosthesis, surgical indications have expanded,^6,7 and dislocation rates appear to have decreased. Although the most common indication for RTSA continues to be cuff tear arthropathy (CTA),⁶ there has been increased use in rheumatoid arthritis^8-10; proximal humerus fractures, especially in cases of poor bone quality and unreliable fixation of tuberosities^11-13; and failed previous shoulder reconstruction.^14,15 As RTSA is performed more often, limiting the complications will become more important for both patient care and economics.

We conducted a study to analyze dislocation rates at our institution and to identify both modifiable and nonmodifiable risk factors for dislocation after RTSA. By identifying risk factors for dislocation, we will be able to implement additional perioperative clinical measures to reduce the incidence of dislocation.

Materials and Methods

This retrospective study of dislocation after RTSA was conducted at the Rothman Institute of Orthopedics and Methodist Hospital (Thomas Jefferson University Hospitals, Philadelphia, PA). After obtaining Institutional Review Board approval for the study, we searched our institution’s electronic database of shoulder arthroplasties to identify all RTSAs performed at our 2 large-volume urban institutions between September 27, 2010 and December 31, 2013. For the record search, International Classification of Diseases, Ninth Revision (ICD-9) codes were used (Table 1).

The medical records of each patient were used to identify independent variables that could be associated with dislocation rate. Demographic variables included sex, age, and race. Preoperative clinical data included body mass index (BMI), etiology of shoulder disease leading to RTSA, individual comorbidities, and Charlson Comorbidity Index (CCI)¹⁶ modified to be used with ICD-9 codes.¹⁷ In addition, prior shoulder surgery history and arthroplasty type (primary or revision) were determined. Postoperative considerations were time to dislocation, mechanism of dislocation, and intervention(s) needed for dislocation. Although the institutional database did not include operative variables such as prosthesis type and surgical approach, all 6 surgeons in this study were using a standard deltopectoral approach in beach-chair position with a Grammont style prosthesis for RTSA cases.

Descriptive statistics for RTSA patients and the dislocation subpopulation were compiled. Bivariate analysis was used to evaluate which of the previously described variables influenced dislocation rates. Last, multivariate logistic regression analysis was performed to evaluate which factors were independent predictors of dislocation. We included demographic variables (age, sex, ethnicity), clinical variables (BMI, individual comorbidities, CCI), and surgical variables (primary vs revision, diagnosis at time of surgery). All statistical analyses were performed with Excel 2013 (Microsoft) and SPSS Statistics Version 20.0 (SPSS Inc.).

Results

From the database, we identified 487 patients who underwent 510 RTSAs during the study period. These surgeries were performed by 6 shoulder and elbow fellowship–trained surgeons. Of the 510 RTSAs, 393 (77.1%) were primary cases, and 117 (22.9%) were revision cases.

Of the 510 shoulders that underwent RTSA, 15 (2.9%; 14 patients) dislocated. Of these 15 cases, 5 were primary (1.3% of all primary cases) and 10 were revision (8.5% of all revision cases). Mean time from index surgery to diagnosis of dislocation was 58.2 days (range, 0-319 days). One dislocation occurred immediately after surgery, 2 after falls, 4 from patient-identified low-energy mechanisms of injury, and 8 without known inciting events. Nine dislocations (60%) did not have a subscapularis repair (7 were irreparable, 2 underwent subscapularis peel without repair), and the other 6 were repaired primarily (Table 2).

Discussion

With more RTSAs being performed, evaluation of their common complications becomes increasingly important.¹⁸ We found a 3.0% rate of dislocation after RTSA, which is consistent with the most recently reported incidence⁴ and falls within the previously described range of 0% to 8.6%.^19-26 Of the clinical risk factors identified in this study, those previously described were prior surgery, subscapularis insufficiency, higher BMI, and male sex.⁴ However, our finding of lower risk of dislocation after RTSA for primary rotator cuff pathology was not previously described. Although Chalmers and colleagues⁴ did not report this lower risk, 3 (27.3%) of their 11 patients with dislocation had primary CTA, compared with 1 (6.7%) of 15 patients in the present study.⁴ Our literature review did not identify any studies that independently reported the dislocation rate in patients who underwent RTSA for rotator cuff failure.

The risk factors of subscapularis irreparability and revision surgery suggest the importance of the soft-tissue envelope and bony anatomy in dislocation prevention. Previous analyses have suggested implant malpositioning,^27,28 poor subscapularis quality,²⁹ and inadequate muscle tensioning^5,30-32 as risk factors for RTSA. Patients with an irreparable subscapularis tendon have often had multiple surgeries with compromise to the muscle/soft-tissue envelope or bony anatomy of the shoulder. A biomechanical study by Gutiérrez and colleagues³¹ found the compressive forces of the soft tissue at the glenohumeral joint to be the most important contributor to stability in the RTSA prosthesis. In clinical studies, the role of the subscapularis in preventing instability after RTSA remains unclear. Edwards and colleagues²⁹ prospectively compared dislocation rates in patients with reparable and irreparable subscapularis tendons during RTSA and found a higher rate of dislocation in the irreparable subscapularis group. Of note, patients in the irreparable subscapularis group also had more complex diagnoses, including proximal humeral nonunion, fixed glenohumeral dislocation, and failed prior arthroplasty. Clark and colleagues³³ retrospectively analyzed subscapularis repair in 2 RTSA groups and found no appreciable effect on complication rate, dislocation events, range-of-motion gains, or pain relief.

Our finding that higher BMI is an independent risk factor was previously described.⁴ The association is unclear but could be related to implant positioning, difficulty in intraoperative assessment of muscle tensioning, or body habitus that may generate a lever arm for impingement and dislocation when the arm is in adduction. Last, our finding that male sex is a risk factor for dislocation approached significance, and this relationship was previously reported.⁴ This could be attributable to a higher rate of activity or of indolent infection in male patients.^34,35Besides studying risk factors for dislocation after RTSA, we investigated treatment. None of our patients were treated successfully and definitively with closed reduction in the clinic. This finding diverges from findings in studies by Teusink and colleagues² and Chalmers and colleagues,⁴who respectively reported 62% and 44% rates of success with closed reduction. Our cohort of 14 patients with 15 dislocations required a total of 17 trips to the operating room after dislocation. This significantly higher rate of return to the operating room suggests that dislocation after RTSA may be a more costly and morbid problem than has been previously described.

This study had several weaknesses. Despite its large consecutive series of patients, the study was retrospective, and several variables that would be documented and controlled in a prospective study could not be measured here. Specifically, neither preoperative physical examination nor patient-specific assessments of pain or function were consistently obtained. Similarly, postoperative patient-specific instruments of outcomes evaluation were not obtained consistently, so results of patients with dislocation could not be compared with those of a control group. In addition, preoperative and postoperative radiographs were not consistently present in our electronic medical records, so the influence of preoperative bony anatomy, intraoperative limb lengthening, and any implant malpositioning could not be determined. Furthermore, operative details, such as reparability of the subscapularis, were not fully available for the control group and could not be included in statistical analysis. In addition, that the known dislocation risk factor of male sex⁴ was identified here but was not significant in multivariate regression analysis suggests that this study may not have been adequately powered to identify a significant difference in dislocation rate between the sexes. Last, though our results suggested associations between the aforementioned variables and dislocation after RTSA, a truly causative relationship could not be confirmed with this study design or analysis. Therefore, our study findings are hypothesis-generating and may indicate a benefit to greater deltoid tensioning, use of retentive liners, or more conservative rehabilitation protocols for high-risk patients.

Conclusion

Dislocation after RTSA is an uncommon complication that often requires a return to the operating room. This study identified a modifiable risk factor (higher BMI) and 3 nonmodifiable risk factors (male sex, subscapularis insufficiency, revision surgery) for dislocation after RTSA. In contrast, patients who undergo RTSA for primary rotator cuff pathology are unlikely to dislocate after surgery. This low risk of dislocation after RTSA for primary cuff pathology was not previously described. Patients in the higher risk category may benefit from preoperative lifestyle modification, intraoperative techniques for increasing stability, and more conservative therapy after surgery. In addition, unlike previous investigations, this study did not find closed reduction in the clinic alone to be successful in definitively treating this patient population.

Am J Orthop. 2016;45(7):E444-E450. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Risk factors for dislocation after reverse total shoulder arthroplasty (RTSA) are not clearly defined. Prosthetic dislocation can result in poor patient satisfaction, worse functional outcomes, and return to the operating room.^1-3 As a result, identification of modifiable risk factors for complications represents an important research initiative for shoulder surgeons.

There is a paucity of literature devoted to the study of dislocation after RTSA. Chalmers and colleagues⁴ found a 2.9% (11/385) incidence of early dislocation within 3 months after index surgery—an improvement over the 15.8% reported for early instability over the period 2004–2006.⁵ As prosthesis design has improved and surgeons have become more comfortable with the RTSA prosthesis, surgical indications have expanded,^6,7 and dislocation rates appear to have decreased. Although the most common indication for RTSA continues to be cuff tear arthropathy (CTA),⁶ there has been increased use in rheumatoid arthritis^8-10; proximal humerus fractures, especially in cases of poor bone quality and unreliable fixation of tuberosities^11-13; and failed previous shoulder reconstruction.^14,15 As RTSA is performed more often, limiting the complications will become more important for both patient care and economics.

We conducted a study to analyze dislocation rates at our institution and to identify both modifiable and nonmodifiable risk factors for dislocation after RTSA. By identifying risk factors for dislocation, we will be able to implement additional perioperative clinical measures to reduce the incidence of dislocation.

Materials and Methods

This retrospective study of dislocation after RTSA was conducted at the Rothman Institute of Orthopedics and Methodist Hospital (Thomas Jefferson University Hospitals, Philadelphia, PA). After obtaining Institutional Review Board approval for the study, we searched our institution’s electronic database of shoulder arthroplasties to identify all RTSAs performed at our 2 large-volume urban institutions between September 27, 2010 and December 31, 2013. For the record search, International Classification of Diseases, Ninth Revision (ICD-9) codes were used (Table 1).

The medical records of each patient were used to identify independent variables that could be associated with dislocation rate. Demographic variables included sex, age, and race. Preoperative clinical data included body mass index (BMI), etiology of shoulder disease leading to RTSA, individual comorbidities, and Charlson Comorbidity Index (CCI)¹⁶ modified to be used with ICD-9 codes.¹⁷ In addition, prior shoulder surgery history and arthroplasty type (primary or revision) were determined. Postoperative considerations were time to dislocation, mechanism of dislocation, and intervention(s) needed for dislocation. Although the institutional database did not include operative variables such as prosthesis type and surgical approach, all 6 surgeons in this study were using a standard deltopectoral approach in beach-chair position with a Grammont style prosthesis for RTSA cases.

Descriptive statistics for RTSA patients and the dislocation subpopulation were compiled. Bivariate analysis was used to evaluate which of the previously described variables influenced dislocation rates. Last, multivariate logistic regression analysis was performed to evaluate which factors were independent predictors of dislocation. We included demographic variables (age, sex, ethnicity), clinical variables (BMI, individual comorbidities, CCI), and surgical variables (primary vs revision, diagnosis at time of surgery). All statistical analyses were performed with Excel 2013 (Microsoft) and SPSS Statistics Version 20.0 (SPSS Inc.).

Results

From the database, we identified 487 patients who underwent 510 RTSAs during the study period. These surgeries were performed by 6 shoulder and elbow fellowship–trained surgeons. Of the 510 RTSAs, 393 (77.1%) were primary cases, and 117 (22.9%) were revision cases.

Of the 510 shoulders that underwent RTSA, 15 (2.9%; 14 patients) dislocated. Of these 15 cases, 5 were primary (1.3% of all primary cases) and 10 were revision (8.5% of all revision cases). Mean time from index surgery to diagnosis of dislocation was 58.2 days (range, 0-319 days). One dislocation occurred immediately after surgery, 2 after falls, 4 from patient-identified low-energy mechanisms of injury, and 8 without known inciting events. Nine dislocations (60%) did not have a subscapularis repair (7 were irreparable, 2 underwent subscapularis peel without repair), and the other 6 were repaired primarily (Table 2).

Discussion

With more RTSAs being performed, evaluation of their common complications becomes increasingly important.¹⁸ We found a 3.0% rate of dislocation after RTSA, which is consistent with the most recently reported incidence⁴ and falls within the previously described range of 0% to 8.6%.^19-26 Of the clinical risk factors identified in this study, those previously described were prior surgery, subscapularis insufficiency, higher BMI, and male sex.⁴ However, our finding of lower risk of dislocation after RTSA for primary rotator cuff pathology was not previously described. Although Chalmers and colleagues⁴ did not report this lower risk, 3 (27.3%) of their 11 patients with dislocation had primary CTA, compared with 1 (6.7%) of 15 patients in the present study.⁴ Our literature review did not identify any studies that independently reported the dislocation rate in patients who underwent RTSA for rotator cuff failure.

The risk factors of subscapularis irreparability and revision surgery suggest the importance of the soft-tissue envelope and bony anatomy in dislocation prevention. Previous analyses have suggested implant malpositioning,^27,28 poor subscapularis quality,²⁹ and inadequate muscle tensioning^5,30-32 as risk factors for RTSA. Patients with an irreparable subscapularis tendon have often had multiple surgeries with compromise to the muscle/soft-tissue envelope or bony anatomy of the shoulder. A biomechanical study by Gutiérrez and colleagues³¹ found the compressive forces of the soft tissue at the glenohumeral joint to be the most important contributor to stability in the RTSA prosthesis. In clinical studies, the role of the subscapularis in preventing instability after RTSA remains unclear. Edwards and colleagues²⁹ prospectively compared dislocation rates in patients with reparable and irreparable subscapularis tendons during RTSA and found a higher rate of dislocation in the irreparable subscapularis group. Of note, patients in the irreparable subscapularis group also had more complex diagnoses, including proximal humeral nonunion, fixed glenohumeral dislocation, and failed prior arthroplasty. Clark and colleagues³³ retrospectively analyzed subscapularis repair in 2 RTSA groups and found no appreciable effect on complication rate, dislocation events, range-of-motion gains, or pain relief.

Our finding that higher BMI is an independent risk factor was previously described.⁴ The association is unclear but could be related to implant positioning, difficulty in intraoperative assessment of muscle tensioning, or body habitus that may generate a lever arm for impingement and dislocation when the arm is in adduction. Last, our finding that male sex is a risk factor for dislocation approached significance, and this relationship was previously reported.⁴ This could be attributable to a higher rate of activity or of indolent infection in male patients.^34,35Besides studying risk factors for dislocation after RTSA, we investigated treatment. None of our patients were treated successfully and definitively with closed reduction in the clinic. This finding diverges from findings in studies by Teusink and colleagues² and Chalmers and colleagues,⁴who respectively reported 62% and 44% rates of success with closed reduction. Our cohort of 14 patients with 15 dislocations required a total of 17 trips to the operating room after dislocation. This significantly higher rate of return to the operating room suggests that dislocation after RTSA may be a more costly and morbid problem than has been previously described.

This study had several weaknesses. Despite its large consecutive series of patients, the study was retrospective, and several variables that would be documented and controlled in a prospective study could not be measured here. Specifically, neither preoperative physical examination nor patient-specific assessments of pain or function were consistently obtained. Similarly, postoperative patient-specific instruments of outcomes evaluation were not obtained consistently, so results of patients with dislocation could not be compared with those of a control group. In addition, preoperative and postoperative radiographs were not consistently present in our electronic medical records, so the influence of preoperative bony anatomy, intraoperative limb lengthening, and any implant malpositioning could not be determined. Furthermore, operative details, such as reparability of the subscapularis, were not fully available for the control group and could not be included in statistical analysis. In addition, that the known dislocation risk factor of male sex⁴ was identified here but was not significant in multivariate regression analysis suggests that this study may not have been adequately powered to identify a significant difference in dislocation rate between the sexes. Last, though our results suggested associations between the aforementioned variables and dislocation after RTSA, a truly causative relationship could not be confirmed with this study design or analysis. Therefore, our study findings are hypothesis-generating and may indicate a benefit to greater deltoid tensioning, use of retentive liners, or more conservative rehabilitation protocols for high-risk patients.

Conclusion

Dislocation after RTSA is an uncommon complication that often requires a return to the operating room. This study identified a modifiable risk factor (higher BMI) and 3 nonmodifiable risk factors (male sex, subscapularis insufficiency, revision surgery) for dislocation after RTSA. In contrast, patients who undergo RTSA for primary rotator cuff pathology are unlikely to dislocate after surgery. This low risk of dislocation after RTSA for primary cuff pathology was not previously described. Patients in the higher risk category may benefit from preoperative lifestyle modification, intraoperative techniques for increasing stability, and more conservative therapy after surgery. In addition, unlike previous investigations, this study did not find closed reduction in the clinic alone to be successful in definitively treating this patient population.

Am J Orthop. 2016;45(7):E444-E450. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The training model for orthopedic resident education has been transformed. Surgeon factors, patient expectations, financial and legal concerns, associated costs, and work hour restrictions have put pressure on resident autonomy in the operating room.^1,2 At the end of resident training, the expectation is that board-eligible surgeons will have the surgical skills necessary to perform a wide range of surgical procedures.^3,4 Helping residents become proficient for independent practice requires a multidisciplinary approach.⁵ This approach, regardless of its details, requires investment in time, resources, expertise, and funding.

Many residency programs are trying to bridge the gap between observation and autonomy with surgical simulation. According to one study, 76% of residency programs have a surgical skills laboratory, and 46% have a structured surgical skills curriculum.⁶Surgical skills preparation is available in different modalities. Synthetic bones, virtual reality, and arthroscopic simulators represent potential opportunities for practice. Through these modalities, residents become more comfortable with the tools used in orthopedic procedures. Cadaveric dissection allows them to practice surgical approaches in the setting of real anatomy.¹ Independent dissection helps them appreciate the planes, layers, and proximity of crucial body structures and understand important surgical anatomy.⁴Surgical simulation can be expensive, and funding comes in many forms. Cadaver laboratories require investment in specimens, facilities, and time away from clinical obligations.⁴ Cadaver availability varies with regional resources, and the cost of a cadaver ranges from $1000 to $2000.^7,8 Arthroscopic simulators and virtual reality programs are expensive as well. These modalities range from a less expensive video box (with standard arthroscopic equipment) to a virtual reality haptic simulation costing a residency program as much as $80,000.⁹ Synthetic bone simulations are less expensive but require investment in faculty time and outside implants and instrumentation.¹⁰ The cost of simulation raises the question of funding sources.

Funding surgical simulation is a challenge. In a national survey of program directors, conducted by Karam and colleagues,⁶ 87.3% of residencies cited lack of funding as the most significant barrier to a formal surgical skills program. Simulation can be residency-sponsored, industry-sponsored, or specialty-sponsored. Karam and colleagues⁶ found that department, hospital, and industry funding were the 3 main sponsors of surgical simulation. Each funding mechanism brings its own set of challenges and opportunities. Industry-sponsored simulation provides a cost-effective outlet for residency programs. However, this type of funding is under scrutiny, as industry funding for education becomes more transparent. In addition, industry funding typically limits the technology that can be used during the simulation to the sponsor’s technology. Courses offered by the American Academy of Orthopaedic Surgeons (AAOS) and a number of subspecialty societies provide less conflicted simulation at reasonable cost.

If residents, residency programs, hospitals, industry, subspecialty societies, and the AAOS are going to invest in resident education through simulation, then the effect of simulation on resident education must be understood. Intuitively, simulation as a modality for improving resident skills makes sense. For residency programs to invest in simulation and surgical skills, different modalities must be objectively evaluated and their utility validated. If simulation is to become valuable, first it must be done correctly.

Kneebone¹¹ proposed a framework for evaluating simulation. In this framework, simulation should allow for sustained, deliberate practice in a safe environment. It should provide access to expert tutors when appropriate. It should map onto real-life clinical experience. Last, it should provide a supportive, motivational, learner-centered milieu. Residents and program directors should consider this framework when deciding which simulation exercises to engage in and which resources to supply for exercises. Having supportive supervision during simulation can lead to a positive outcome. Likewise, learning incorrect techniques or bad habits or having inexperienced teachers can have the opposite effect.

Several authors have reviewed the evidence and found simulation to be an important part of orthopedic resident education.^{1,2,4,9,12,13} They have evaluated cadaveric simulation, synthetic bone simulation, arthroscopic simulation, and virtual reality simulation. Their studies demonstrated that simulation is an effective tool and provided objective criteria for evaluating residents on a larger scale. In a blinded, randomized study by Howells and colleagues,¹⁴ junior residents were either trained on a knee simulator or received no training before evaluation. Those who received the training scored significantly better than their peers on validated assessment measures.

The literature on different modalities shows simulation is an effective teaching tool for general orthopedic surgical skills⁵; knee, shoulder, and ankle arthroscopy^14-21; spine surgery²²; and orthopedic trauma surgery.^23-26 Investigators in several other surgical specialties have studied the utility of simulation, and many are incorporating simulation into their resident curricula.

More effective simulation seems correlated with a yearlong structured curriculum rather than with intermittent, isolated experiences.³ Dunn and colleagues²⁷ evaluated arthroscopic shoulder simulation 1 year after a training exercise. The group that received formal training did better than the control group on an initial arthroscopic surgery skill evaluation tool. At 1 year, however, the gains made through training were lost.

Simulation is a new paradigm for resident education. It offers multiple opportunities and challenges for residents, residency programs, industry partners, specialty and subspecialty societies, and medical examiners. The Accreditation Council for Graduate Medical Education’s ACGME Program Requirements for Graduate Medical Education in Orthopaedic Surgery requires of residency programs a didactic curriculum dedicated to basic motor skills in addition to a dedicated space for facilitating basic surgical skills training.²⁸ Residency programs must demonstrate to ACGME their commitment to surgical skills training and simulation. Implementation of simulation for resident education has many variables, including funding, type of simulation, demonstrated efficacy, provision of supervision, resident time, and establishment of a formal curriculum. Residents and residency programs should embrace this changing paradigm to bridge the gap between observation and autonomy in orthopedic surgical and arthroscopic technique.

Am J Orthop. 2016;45(7):E426-E428. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The training model for orthopedic resident education has been transformed. Surgeon factors, patient expectations, financial and legal concerns, associated costs, and work hour restrictions have put pressure on resident autonomy in the operating room.^1,2 At the end of resident training, the expectation is that board-eligible surgeons will have the surgical skills necessary to perform a wide range of surgical procedures.^3,4 Helping residents become proficient for independent practice requires a multidisciplinary approach.⁵ This approach, regardless of its details, requires investment in time, resources, expertise, and funding.

Many residency programs are trying to bridge the gap between observation and autonomy with surgical simulation. According to one study, 76% of residency programs have a surgical skills laboratory, and 46% have a structured surgical skills curriculum.⁶Surgical skills preparation is available in different modalities. Synthetic bones, virtual reality, and arthroscopic simulators represent potential opportunities for practice. Through these modalities, residents become more comfortable with the tools used in orthopedic procedures. Cadaveric dissection allows them to practice surgical approaches in the setting of real anatomy.¹ Independent dissection helps them appreciate the planes, layers, and proximity of crucial body structures and understand important surgical anatomy.⁴Surgical simulation can be expensive, and funding comes in many forms. Cadaver laboratories require investment in specimens, facilities, and time away from clinical obligations.⁴ Cadaver availability varies with regional resources, and the cost of a cadaver ranges from $1000 to $2000.^7,8 Arthroscopic simulators and virtual reality programs are expensive as well. These modalities range from a less expensive video box (with standard arthroscopic equipment) to a virtual reality haptic simulation costing a residency program as much as $80,000.⁹ Synthetic bone simulations are less expensive but require investment in faculty time and outside implants and instrumentation.¹⁰ The cost of simulation raises the question of funding sources.

Funding surgical simulation is a challenge. In a national survey of program directors, conducted by Karam and colleagues,⁶ 87.3% of residencies cited lack of funding as the most significant barrier to a formal surgical skills program. Simulation can be residency-sponsored, industry-sponsored, or specialty-sponsored. Karam and colleagues⁶ found that department, hospital, and industry funding were the 3 main sponsors of surgical simulation. Each funding mechanism brings its own set of challenges and opportunities. Industry-sponsored simulation provides a cost-effective outlet for residency programs. However, this type of funding is under scrutiny, as industry funding for education becomes more transparent. In addition, industry funding typically limits the technology that can be used during the simulation to the sponsor’s technology. Courses offered by the American Academy of Orthopaedic Surgeons (AAOS) and a number of subspecialty societies provide less conflicted simulation at reasonable cost.

If residents, residency programs, hospitals, industry, subspecialty societies, and the AAOS are going to invest in resident education through simulation, then the effect of simulation on resident education must be understood. Intuitively, simulation as a modality for improving resident skills makes sense. For residency programs to invest in simulation and surgical skills, different modalities must be objectively evaluated and their utility validated. If simulation is to become valuable, first it must be done correctly.

Kneebone¹¹ proposed a framework for evaluating simulation. In this framework, simulation should allow for sustained, deliberate practice in a safe environment. It should provide access to expert tutors when appropriate. It should map onto real-life clinical experience. Last, it should provide a supportive, motivational, learner-centered milieu. Residents and program directors should consider this framework when deciding which simulation exercises to engage in and which resources to supply for exercises. Having supportive supervision during simulation can lead to a positive outcome. Likewise, learning incorrect techniques or bad habits or having inexperienced teachers can have the opposite effect.

Several authors have reviewed the evidence and found simulation to be an important part of orthopedic resident education.^{1,2,4,9,12,13} They have evaluated cadaveric simulation, synthetic bone simulation, arthroscopic simulation, and virtual reality simulation. Their studies demonstrated that simulation is an effective tool and provided objective criteria for evaluating residents on a larger scale. In a blinded, randomized study by Howells and colleagues,¹⁴ junior residents were either trained on a knee simulator or received no training before evaluation. Those who received the training scored significantly better than their peers on validated assessment measures.

The literature on different modalities shows simulation is an effective teaching tool for general orthopedic surgical skills⁵; knee, shoulder, and ankle arthroscopy^14-21; spine surgery²²; and orthopedic trauma surgery.^23-26 Investigators in several other surgical specialties have studied the utility of simulation, and many are incorporating simulation into their resident curricula.

More effective simulation seems correlated with a yearlong structured curriculum rather than with intermittent, isolated experiences.³ Dunn and colleagues²⁷ evaluated arthroscopic shoulder simulation 1 year after a training exercise. The group that received formal training did better than the control group on an initial arthroscopic surgery skill evaluation tool. At 1 year, however, the gains made through training were lost.

Simulation is a new paradigm for resident education. It offers multiple opportunities and challenges for residents, residency programs, industry partners, specialty and subspecialty societies, and medical examiners. The Accreditation Council for Graduate Medical Education’s ACGME Program Requirements for Graduate Medical Education in Orthopaedic Surgery requires of residency programs a didactic curriculum dedicated to basic motor skills in addition to a dedicated space for facilitating basic surgical skills training.²⁸ Residency programs must demonstrate to ACGME their commitment to surgical skills training and simulation. Implementation of simulation for resident education has many variables, including funding, type of simulation, demonstrated efficacy, provision of supervision, resident time, and establishment of a formal curriculum. Residents and residency programs should embrace this changing paradigm to bridge the gap between observation and autonomy in orthopedic surgical and arthroscopic technique.

Am J Orthop. 2016;45(7):E426-E428. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The training model for orthopedic resident education has been transformed. Surgeon factors, patient expectations, financial and legal concerns, associated costs, and work hour restrictions have put pressure on resident autonomy in the operating room.^1,2 At the end of resident training, the expectation is that board-eligible surgeons will have the surgical skills necessary to perform a wide range of surgical procedures.^3,4 Helping residents become proficient for independent practice requires a multidisciplinary approach.⁵ This approach, regardless of its details, requires investment in time, resources, expertise, and funding.

Many residency programs are trying to bridge the gap between observation and autonomy with surgical simulation. According to one study, 76% of residency programs have a surgical skills laboratory, and 46% have a structured surgical skills curriculum.⁶Surgical skills preparation is available in different modalities. Synthetic bones, virtual reality, and arthroscopic simulators represent potential opportunities for practice. Through these modalities, residents become more comfortable with the tools used in orthopedic procedures. Cadaveric dissection allows them to practice surgical approaches in the setting of real anatomy.¹ Independent dissection helps them appreciate the planes, layers, and proximity of crucial body structures and understand important surgical anatomy.⁴Surgical simulation can be expensive, and funding comes in many forms. Cadaver laboratories require investment in specimens, facilities, and time away from clinical obligations.⁴ Cadaver availability varies with regional resources, and the cost of a cadaver ranges from $1000 to $2000.^7,8 Arthroscopic simulators and virtual reality programs are expensive as well. These modalities range from a less expensive video box (with standard arthroscopic equipment) to a virtual reality haptic simulation costing a residency program as much as $80,000.⁹ Synthetic bone simulations are less expensive but require investment in faculty time and outside implants and instrumentation.¹⁰ The cost of simulation raises the question of funding sources.

Funding surgical simulation is a challenge. In a national survey of program directors, conducted by Karam and colleagues,⁶ 87.3% of residencies cited lack of funding as the most significant barrier to a formal surgical skills program. Simulation can be residency-sponsored, industry-sponsored, or specialty-sponsored. Karam and colleagues⁶ found that department, hospital, and industry funding were the 3 main sponsors of surgical simulation. Each funding mechanism brings its own set of challenges and opportunities. Industry-sponsored simulation provides a cost-effective outlet for residency programs. However, this type of funding is under scrutiny, as industry funding for education becomes more transparent. In addition, industry funding typically limits the technology that can be used during the simulation to the sponsor’s technology. Courses offered by the American Academy of Orthopaedic Surgeons (AAOS) and a number of subspecialty societies provide less conflicted simulation at reasonable cost.

If residents, residency programs, hospitals, industry, subspecialty societies, and the AAOS are going to invest in resident education through simulation, then the effect of simulation on resident education must be understood. Intuitively, simulation as a modality for improving resident skills makes sense. For residency programs to invest in simulation and surgical skills, different modalities must be objectively evaluated and their utility validated. If simulation is to become valuable, first it must be done correctly.

Kneebone¹¹ proposed a framework for evaluating simulation. In this framework, simulation should allow for sustained, deliberate practice in a safe environment. It should provide access to expert tutors when appropriate. It should map onto real-life clinical experience. Last, it should provide a supportive, motivational, learner-centered milieu. Residents and program directors should consider this framework when deciding which simulation exercises to engage in and which resources to supply for exercises. Having supportive supervision during simulation can lead to a positive outcome. Likewise, learning incorrect techniques or bad habits or having inexperienced teachers can have the opposite effect.

Several authors have reviewed the evidence and found simulation to be an important part of orthopedic resident education.^{1,2,4,9,12,13} They have evaluated cadaveric simulation, synthetic bone simulation, arthroscopic simulation, and virtual reality simulation. Their studies demonstrated that simulation is an effective tool and provided objective criteria for evaluating residents on a larger scale. In a blinded, randomized study by Howells and colleagues,¹⁴ junior residents were either trained on a knee simulator or received no training before evaluation. Those who received the training scored significantly better than their peers on validated assessment measures.

The literature on different modalities shows simulation is an effective teaching tool for general orthopedic surgical skills⁵; knee, shoulder, and ankle arthroscopy^14-21; spine surgery²²; and orthopedic trauma surgery.^23-26 Investigators in several other surgical specialties have studied the utility of simulation, and many are incorporating simulation into their resident curricula.

More effective simulation seems correlated with a yearlong structured curriculum rather than with intermittent, isolated experiences.³ Dunn and colleagues²⁷ evaluated arthroscopic shoulder simulation 1 year after a training exercise. The group that received formal training did better than the control group on an initial arthroscopic surgery skill evaluation tool. At 1 year, however, the gains made through training were lost.

Simulation is a new paradigm for resident education. It offers multiple opportunities and challenges for residents, residency programs, industry partners, specialty and subspecialty societies, and medical examiners. The Accreditation Council for Graduate Medical Education’s ACGME Program Requirements for Graduate Medical Education in Orthopaedic Surgery requires of residency programs a didactic curriculum dedicated to basic motor skills in addition to a dedicated space for facilitating basic surgical skills training.²⁸ Residency programs must demonstrate to ACGME their commitment to surgical skills training and simulation. Implementation of simulation for resident education has many variables, including funding, type of simulation, demonstrated efficacy, provision of supervision, resident time, and establishment of a formal curriculum. Residents and residency programs should embrace this changing paradigm to bridge the gap between observation and autonomy in orthopedic surgical and arthroscopic technique.

Am J Orthop. 2016;45(7):E426-E428. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

WASHINGTON – Biologic agents should be stopped prior to elective total knee or hip arthroplasty in patients with rheumatic diseases, according to a draft guideline developed by the American College of Rheumatology and the American Association of Hip and Knee Surgeons.

The guideline, which address the perioperative management of antirheumatic medications in patients with rheumatoid arthritis, spondyloarthritis, psoriatic arthritis, juvenile idiopathic arthritis (JIA), or lupus who are undergoing such surgery, is currently under review, Dr. Susan Goodman, MD, coprincipal investigator, reported at the annual meeting of the American College of Rheumatology.

The draft guideline was created because “guidance was needed for common clinical situations, even where data were sparse. We didn’t want to configure treatment mandates – that’s not what these are,” Dr. Goodman of Cornell University, New York, said.

The recommendations are conditional, she said, meaning that the benefits probably outweigh the harms, that the recommendations apply to most but not all patients, and that future research may lead to changes.

“They’re also preference sensitive,” she said, explaining that patients’ values and preferences should be carefully considered, as they might differ from those of the patient panel consulted during guideline development; the panel expressed greater concern about the risk of infection following surgery than about perioperative flares resulting from medication discontinuation.

Based on agreement by at least 80% of a voting panel which considered available evidence in the context of their clinical experience along with the input from the patient panel, the draft guideline states that:

• Current doses of methotrexate, leflunomide, hydroxychloroquine, and sulfasalazine should be continued in patients with rheumatic diseases undergoing elective hip and knee replacement. This recommendation is based on an extensive literature review that showed the infection rate is decreased in patients who continue these medications, Dr. Goodman said.

• All biologics should be withheld prior to surgery in patients with inflammatory arthritis, and surgery should be planned for the end of the dosing cycle. This matter wasn’t specifically addressed in the literature; however, numerous randomized controlled trials outside of the surgical setting demonstrate an increased risk of infection associated with their use, she noted.

“All of the biologic medications were found to be associated with an increased risk of infection,” she said. “Because of this and the level of importance patients place on minimizing infection risk, we’ve recommended that biologics be withheld prior to surgery.”

• Tofacitinib, which was considered in a separate oral, targeted therapy category, should be withheld for at least 7 days prior to surgery in patients with RA, spondyloarthritis, and JIA. Data from systematic reviews and meta-analyses showed an increased risk of infection with tofacitinib, although more research is needed in order to “firm up” this recommendation, Dr. Goodman said.

• In lupus patients, rituximab and belimumab should be withheld prior to surgery, and surgery should be planned for the end of the dosing period.

“Again, this was not answered in the literature. We depended on observational studies that we reviewed that did show that patients with severe active lupus were at much higher risk for adverse events. But since rituximab isn’t approved by the [Food and Drug Administration] for use in lupus, and belimumab isn’t approved for use in severe lupus – and those seem to be the high-risk patients – we thought withholding them was more prudent,” she said.

• Patients with severe lupus should continue on current doses of methotrexate, mycophenolic acid, azathioprine, mizoribine, cyclosporine, and tacrolimus through surgery. This recommendation is based on indirect data from experience in organ transplant patients.

• All medications should be discontinued in patients whose lupus is not severe.

“Our recommendation is to withhold for 7 days to 2-5 days after surgery in the absence of any wound healing complications or any other complications,” she said, noting that the literature does not directly address this; the recommendation is based on indirect evidence in patients with either active infection or who are at risk for infection.

“We thought that careful monitoring of the patient would permit us to identify flare and intervene quickly. … and that, for mild cases of lupus, the morbidity associated with infection might not be greater than the morbidity associated with the disease flare,” she said.

• Biologics should be restarted once surgical wounds show evidence of healing and there is no clinical evidence of infection. The literature does not directly address this; the recommendation is based on the rationale for use of these medications in patients with either active infection or risk for infection.

• Current daily doses of glucocorticoids, rather than supraphysiologic doses, should be continued in adults with RA, lupus, or inflammatory arthritis. A meta-analysis and systematic review of randomized controlled trial data and observational data showed no hemodynamic difference between daily doses and stress doses.

“In addition, there are abundant observational data demonstrating an increase in infection in patients on chronic steroids greater than 15 mg, and we thought that part of the optimization of the patient would be getting them on the lowest possible steroid dose,” she said, stressing that this refers only to adults receiving glucocorticoids for their rheumatic disease, and not to those with a history of JIA who may have received steroids during development, or to those receiving glucocorticoids for primary, adrenal, or hypothalamic disease.

According to Dr. Goodman, the time is right for the introduction of these recommendations, because the increased use of disease-modifying drugs and biologics means that most patients coming in for these surgeries will be taking these medications.

Further, despite the widespread use of the medications, the rate of total knee and hip arthroplasty surgeries among patients with rheumatic diseases is about the same as it was 20 or 30 years ago – and their risk for devastating complications, including infections, remains high, she said, noting that appropriate medication management provides an opportunity to mitigate risk.

Coprincipal investigator, Bryan Springer, MD, further emphasized the importance of the guideline, noting that the 5-year survival among rheumatic disease patients who develop certain perioperative complications is lower than for many common cancers, and that the literature offers little guidance on managing medications in the perioperative period.

“We now have a document that’s based on the available evidence, and also based on expert opinion, to help us manage these patients much more thoroughly in the perioperative period,” Dr. Springer, an orthopedic surgeon in Charlotte, N.C., said during a press briefing on the guideline.

Dr. Springer highlighted the value of the unique collaboration between the ACR and the AAHKS, calling the effort a win both for patients, and for “collaborative efforts, collaborative research, which we just really don’t do enough of,” he said. “I hope this is a huge step towards that direction.”

This guideline development process was funded by the ACR and AAHKS.

sworcester@frontlinemedcom.com

WASHINGTON – Biologic agents should be stopped prior to elective total knee or hip arthroplasty in patients with rheumatic diseases, according to a draft guideline developed by the American College of Rheumatology and the American Association of Hip and Knee Surgeons.

The guideline, which address the perioperative management of antirheumatic medications in patients with rheumatoid arthritis, spondyloarthritis, psoriatic arthritis, juvenile idiopathic arthritis (JIA), or lupus who are undergoing such surgery, is currently under review, Dr. Susan Goodman, MD, coprincipal investigator, reported at the annual meeting of the American College of Rheumatology.

The draft guideline was created because “guidance was needed for common clinical situations, even where data were sparse. We didn’t want to configure treatment mandates – that’s not what these are,” Dr. Goodman of Cornell University, New York, said.

The recommendations are conditional, she said, meaning that the benefits probably outweigh the harms, that the recommendations apply to most but not all patients, and that future research may lead to changes.

“They’re also preference sensitive,” she said, explaining that patients’ values and preferences should be carefully considered, as they might differ from those of the patient panel consulted during guideline development; the panel expressed greater concern about the risk of infection following surgery than about perioperative flares resulting from medication discontinuation.

Based on agreement by at least 80% of a voting panel which considered available evidence in the context of their clinical experience along with the input from the patient panel, the draft guideline states that:

• Current doses of methotrexate, leflunomide, hydroxychloroquine, and sulfasalazine should be continued in patients with rheumatic diseases undergoing elective hip and knee replacement. This recommendation is based on an extensive literature review that showed the infection rate is decreased in patients who continue these medications, Dr. Goodman said.

• All biologics should be withheld prior to surgery in patients with inflammatory arthritis, and surgery should be planned for the end of the dosing cycle. This matter wasn’t specifically addressed in the literature; however, numerous randomized controlled trials outside of the surgical setting demonstrate an increased risk of infection associated with their use, she noted.

“All of the biologic medications were found to be associated with an increased risk of infection,” she said. “Because of this and the level of importance patients place on minimizing infection risk, we’ve recommended that biologics be withheld prior to surgery.”

• Tofacitinib, which was considered in a separate oral, targeted therapy category, should be withheld for at least 7 days prior to surgery in patients with RA, spondyloarthritis, and JIA. Data from systematic reviews and meta-analyses showed an increased risk of infection with tofacitinib, although more research is needed in order to “firm up” this recommendation, Dr. Goodman said.

• In lupus patients, rituximab and belimumab should be withheld prior to surgery, and surgery should be planned for the end of the dosing period.

“Again, this was not answered in the literature. We depended on observational studies that we reviewed that did show that patients with severe active lupus were at much higher risk for adverse events. But since rituximab isn’t approved by the [Food and Drug Administration] for use in lupus, and belimumab isn’t approved for use in severe lupus – and those seem to be the high-risk patients – we thought withholding them was more prudent,” she said.

• Patients with severe lupus should continue on current doses of methotrexate, mycophenolic acid, azathioprine, mizoribine, cyclosporine, and tacrolimus through surgery. This recommendation is based on indirect data from experience in organ transplant patients.

• All medications should be discontinued in patients whose lupus is not severe.

“Our recommendation is to withhold for 7 days to 2-5 days after surgery in the absence of any wound healing complications or any other complications,” she said, noting that the literature does not directly address this; the recommendation is based on indirect evidence in patients with either active infection or who are at risk for infection.

“We thought that careful monitoring of the patient would permit us to identify flare and intervene quickly. … and that, for mild cases of lupus, the morbidity associated with infection might not be greater than the morbidity associated with the disease flare,” she said.

• Biologics should be restarted once surgical wounds show evidence of healing and there is no clinical evidence of infection. The literature does not directly address this; the recommendation is based on the rationale for use of these medications in patients with either active infection or risk for infection.

• Current daily doses of glucocorticoids, rather than supraphysiologic doses, should be continued in adults with RA, lupus, or inflammatory arthritis. A meta-analysis and systematic review of randomized controlled trial data and observational data showed no hemodynamic difference between daily doses and stress doses.

“In addition, there are abundant observational data demonstrating an increase in infection in patients on chronic steroids greater than 15 mg, and we thought that part of the optimization of the patient would be getting them on the lowest possible steroid dose,” she said, stressing that this refers only to adults receiving glucocorticoids for their rheumatic disease, and not to those with a history of JIA who may have received steroids during development, or to those receiving glucocorticoids for primary, adrenal, or hypothalamic disease.

According to Dr. Goodman, the time is right for the introduction of these recommendations, because the increased use of disease-modifying drugs and biologics means that most patients coming in for these surgeries will be taking these medications.

Further, despite the widespread use of the medications, the rate of total knee and hip arthroplasty surgeries among patients with rheumatic diseases is about the same as it was 20 or 30 years ago – and their risk for devastating complications, including infections, remains high, she said, noting that appropriate medication management provides an opportunity to mitigate risk.

Coprincipal investigator, Bryan Springer, MD, further emphasized the importance of the guideline, noting that the 5-year survival among rheumatic disease patients who develop certain perioperative complications is lower than for many common cancers, and that the literature offers little guidance on managing medications in the perioperative period.

“We now have a document that’s based on the available evidence, and also based on expert opinion, to help us manage these patients much more thoroughly in the perioperative period,” Dr. Springer, an orthopedic surgeon in Charlotte, N.C., said during a press briefing on the guideline.

Dr. Springer highlighted the value of the unique collaboration between the ACR and the AAHKS, calling the effort a win both for patients, and for “collaborative efforts, collaborative research, which we just really don’t do enough of,” he said. “I hope this is a huge step towards that direction.”

This guideline development process was funded by the ACR and AAHKS.

sworcester@frontlinemedcom.com

WASHINGTON – Biologic agents should be stopped prior to elective total knee or hip arthroplasty in patients with rheumatic diseases, according to a draft guideline developed by the American College of Rheumatology and the American Association of Hip and Knee Surgeons.

The guideline, which address the perioperative management of antirheumatic medications in patients with rheumatoid arthritis, spondyloarthritis, psoriatic arthritis, juvenile idiopathic arthritis (JIA), or lupus who are undergoing such surgery, is currently under review, Dr. Susan Goodman, MD, coprincipal investigator, reported at the annual meeting of the American College of Rheumatology.

The draft guideline was created because “guidance was needed for common clinical situations, even where data were sparse. We didn’t want to configure treatment mandates – that’s not what these are,” Dr. Goodman of Cornell University, New York, said.

The recommendations are conditional, she said, meaning that the benefits probably outweigh the harms, that the recommendations apply to most but not all patients, and that future research may lead to changes.

“They’re also preference sensitive,” she said, explaining that patients’ values and preferences should be carefully considered, as they might differ from those of the patient panel consulted during guideline development; the panel expressed greater concern about the risk of infection following surgery than about perioperative flares resulting from medication discontinuation.

Based on agreement by at least 80% of a voting panel which considered available evidence in the context of their clinical experience along with the input from the patient panel, the draft guideline states that:

• Current doses of methotrexate, leflunomide, hydroxychloroquine, and sulfasalazine should be continued in patients with rheumatic diseases undergoing elective hip and knee replacement. This recommendation is based on an extensive literature review that showed the infection rate is decreased in patients who continue these medications, Dr. Goodman said.

• All biologics should be withheld prior to surgery in patients with inflammatory arthritis, and surgery should be planned for the end of the dosing cycle. This matter wasn’t specifically addressed in the literature; however, numerous randomized controlled trials outside of the surgical setting demonstrate an increased risk of infection associated with their use, she noted.

“All of the biologic medications were found to be associated with an increased risk of infection,” she said. “Because of this and the level of importance patients place on minimizing infection risk, we’ve recommended that biologics be withheld prior to surgery.”

• Tofacitinib, which was considered in a separate oral, targeted therapy category, should be withheld for at least 7 days prior to surgery in patients with RA, spondyloarthritis, and JIA. Data from systematic reviews and meta-analyses showed an increased risk of infection with tofacitinib, although more research is needed in order to “firm up” this recommendation, Dr. Goodman said.

• In lupus patients, rituximab and belimumab should be withheld prior to surgery, and surgery should be planned for the end of the dosing period.

“Again, this was not answered in the literature. We depended on observational studies that we reviewed that did show that patients with severe active lupus were at much higher risk for adverse events. But since rituximab isn’t approved by the [Food and Drug Administration] for use in lupus, and belimumab isn’t approved for use in severe lupus – and those seem to be the high-risk patients – we thought withholding them was more prudent,” she said.

• Patients with severe lupus should continue on current doses of methotrexate, mycophenolic acid, azathioprine, mizoribine, cyclosporine, and tacrolimus through surgery. This recommendation is based on indirect data from experience in organ transplant patients.

• All medications should be discontinued in patients whose lupus is not severe.

“Our recommendation is to withhold for 7 days to 2-5 days after surgery in the absence of any wound healing complications or any other complications,” she said, noting that the literature does not directly address this; the recommendation is based on indirect evidence in patients with either active infection or who are at risk for infection.

“We thought that careful monitoring of the patient would permit us to identify flare and intervene quickly. … and that, for mild cases of lupus, the morbidity associated with infection might not be greater than the morbidity associated with the disease flare,” she said.

• Biologics should be restarted once surgical wounds show evidence of healing and there is no clinical evidence of infection. The literature does not directly address this; the recommendation is based on the rationale for use of these medications in patients with either active infection or risk for infection.

• Current daily doses of glucocorticoids, rather than supraphysiologic doses, should be continued in adults with RA, lupus, or inflammatory arthritis. A meta-analysis and systematic review of randomized controlled trial data and observational data showed no hemodynamic difference between daily doses and stress doses.

“In addition, there are abundant observational data demonstrating an increase in infection in patients on chronic steroids greater than 15 mg, and we thought that part of the optimization of the patient would be getting them on the lowest possible steroid dose,” she said, stressing that this refers only to adults receiving glucocorticoids for their rheumatic disease, and not to those with a history of JIA who may have received steroids during development, or to those receiving glucocorticoids for primary, adrenal, or hypothalamic disease.

According to Dr. Goodman, the time is right for the introduction of these recommendations, because the increased use of disease-modifying drugs and biologics means that most patients coming in for these surgeries will be taking these medications.

Further, despite the widespread use of the medications, the rate of total knee and hip arthroplasty surgeries among patients with rheumatic diseases is about the same as it was 20 or 30 years ago – and their risk for devastating complications, including infections, remains high, she said, noting that appropriate medication management provides an opportunity to mitigate risk.

Coprincipal investigator, Bryan Springer, MD, further emphasized the importance of the guideline, noting that the 5-year survival among rheumatic disease patients who develop certain perioperative complications is lower than for many common cancers, and that the literature offers little guidance on managing medications in the perioperative period.

“We now have a document that’s based on the available evidence, and also based on expert opinion, to help us manage these patients much more thoroughly in the perioperative period,” Dr. Springer, an orthopedic surgeon in Charlotte, N.C., said during a press briefing on the guideline.

Dr. Springer highlighted the value of the unique collaboration between the ACR and the AAHKS, calling the effort a win both for patients, and for “collaborative efforts, collaborative research, which we just really don’t do enough of,” he said. “I hope this is a huge step towards that direction.”

This guideline development process was funded by the ACR and AAHKS.

sworcester@frontlinemedcom.com

The rate of medical visits for rotator cuff pathology and the US incidence of arthroscopic rotator cuff repair (RCR) have increased over the past 10 years.¹ The increased use of RCR has been justified with improved patient outcomes.^2,3 Advances in surgical techniques and instrumentation have contributed to better outcomes for patients with rotator cuff pathology.^3-5 Several studies have validated RCR with functional outcome measures, cost–benefit analysis, and health-related quality-of-life measurements.^6-9

Healthcare reimbursement models are being changed to include capitated care, pay for performance, and penalties.¹⁰ Given the changing healthcare climate and the increasing incidence of RCR, it is becoming increasingly important for orthopedic surgeons to critically evaluate and modify their practice and procedures to decrease costs without compromising outcomes.¹¹ RCR outcome studies have focused on comparing open/mini-open with arthroscopic techniques, and single-row with double-row techniques, among others.^4,12-18 Furthermore, several studies on the cost-effectiveness of these surgical techniques have been conducted.^19-21Arthroscopic anchorless (transosseous [TO]) RCR, which is increasingly popular,²² combines the minimal invasiveness of arthroscopic procedures with the biomechanical strength of open TO repair. In addition, this technique avoids the potential complications and costs associated with suture anchors, such as anchor pullout and greater tuberosity osteolysis.^22,23 Several studies have documented the effectiveness of this technique.^24-26 Biomechanical and clinical outcome data supporting arthroscopic TO-RCR have been published, but there are no reports of studies that have analyzed the cost savings associated with this technique.

In this study, we compared implant costs associated with arthroscopic TO-RCR and arthroscopic TO-equivalent (TOE) RCR. We also evaluated these techniques’ operative time and outcomes. Our hypothesis was that arthroscopic TO-RCR can be performed at lower cost and without increasing operative time or compromising outcomes.

Materials and Methods

Our Institutional Review Board approved this study. Between February 2013 and January 2014, participating surgeons performed 43 arthroscopic TO-RCRs that met the study’s inclusion criteria. Twenty-one of the 43 patients enrolled and became the study group. The control group of 21 patients, who underwent arthroscopic TOE-RCR the preceding year (between January 2012 and January 2013), was matched to the study group on tear size and concomitant procedures, including biceps treatment, labral treatment, acromioplasty, and distal clavicle excision (Table 1).

The primary outcome measure was implant cost (amount paid by institution). Cost was determined and reported by an independent third party using Cerner Surginet as the operating room documentation system and McKessen Pathways Materials Management System for item pricing.

All arthroscopic RCRs were performed by 1 of 3 orthopedic surgeons fellowship-trained in either sports medicine or shoulder and elbow surgery. Using the Cofield classification,²⁷ the treating surgeon recorded the size of the rotator cuff tear: small (<1 cm), medium (1-3 cm), large (3-5 cm), massive (>5 cm). The surgeon also recorded the number of suture anchors used, repair technique, biceps treatment, execution of subacromial decompression, execution of distal clavicle excision, and intraoperative complications. TO repair surgical technique is described in the next section. TOE repair was double-row repair with suture anchors. The number of suture anchors varied by tear size: small (3 anchors), medium (2-5 anchors), large (4-6 anchors), massive (4-5 anchors).

Secondary outcome measures were operative time (time from cut to close) and scores on pain VAS (visual analog scale), SANE (Single Assessment Numeric Evaluation), and SST (Simple Shoulder Test). Demographic information was also obtained: age, sex, body mass index, smoking status (Table 1). All patients were asked to fill out questionnaires before surgery and 3, 6, and >12 months after surgery. Outcome surveys were scored by a single research coordinator, who recorded each patient’s outcome scores at the preoperative and postoperative intervals. Follow-up of >12 months was reached by 17 (81%) of the 21 TO patients and 14 (67%) of the 21 TOE patients. For >12 months, the overall rate of follow-up was 74%.

All patients followed the same postoperative rehabilitation protocol: sling immobilization with pendulums for 6 weeks starting at 2 weeks, passive range of motion starting at 6 weeks, and active range of motion starting at 8 weeks. At 3 months, they were allowed progressive resistant exercises with a 10-pound limit, and at 4.5 months they progressed to a 20-pound limit. At 6 months, they were cleared for discharge.

Surgical Technique: Arthroscopic Transosseous Repair

Surgery was performed with the patient in either the beach-chair position or the lateral decubitus position, based on surgeon preference. Our technique is similar to what has been described in the past.^22,28 The glenohumeral joint is accessed through a standard posterior portal, followed by an anterior accessory portal through the rotator interval. Standard diagnostic arthroscopy is performed and intra-articular pathology addressed. Next, the scope is placed in the subacromial space through the posterior portal. A lateral subacromial portal is established and cannulated, and a bursectomy performed. The scope is then placed in a posterolateral portal for better visualization of the rotator cuff tear. The greater tuberosity is débrided with a curette to prepare the bed for repair. An ArthroTunneler (Tornier) is used to pass sutures through the greater tuberosity. For standard 2-tunnel repair, 3 sutures are placed through each tunnel. All 6 sutures are next passed (using a suture passer) through the rotator cuff. The second and fifth suture ends that are passed through the cuff are brought out through the cannula and tied together. They are then brought into the shoulder by pulling on the opposite ends and tied alongside the greater tuberosity to create a box stitch. The box stitch acts as a medial row fixation and as a rip stitch that strengthens the vertical mattress sutures against pullout. The other 4 sutures are tied in vertical mattress configuration.

Statistical Analysis

After obtaining the TO and TOE implant costs, we compared them using a generalized linear model with negative binomial distribution and an identity link function so returned parameters were in additive dollars. This comparison included evaluation of tear size and concomitant procedures. Operative times for TO and TOE were obtained and evaluated, and then compared using time-to-event analysis and the log-rank test. Outcome scores were obtained from patients at baseline and 3, 6, and >12 months after surgery and were compared using a linear mixed model that identified change in outcome scores over time, and difference in outcome scores between the TO and TOE groups.

Results

Table 1 lists patient demographics, including age, sex, body mass index, smoking status, and concomitant procedures. The TO and TOE groups had identical tear-size distributions. In addition, they had similar numbers of concomitant procedures, though our study was underpowered to confirm equivalence. Treatment techniques differed: more biceps tenodesis cases in the TO group (n = 12) than in the TOE group (n = 2) and more biceps tenotomy cases in the TOE group (n = 8) than in the TO group (n = 1).

TO implant cost was significantly lower than TOE implant cost for all tear sizes and independent of concomitant procedures (Figure 1).

Discussion

RCR is one of the most common orthopedic surgical procedures, and its use has increased over the past decade.^9,21 This increase coincides with the emergence of new repair techniques and implants. These advancements come at a cost. Given the increasingly cost-conscious healthcare environment and its changing reimbursement models, now surgeons must evaluate the economics of their surgical procedures in an attempt to decrease costs without compromising outcomes. We hypothesized that arthroscopic TO-RCR can be performed at lower cost relative to arthroscopic TOE-RCR and without increasing operative time or compromising short-term outcomes.

Studies on the cost-effectiveness of different RCR techniques have been conducted.^19-21 Adla and colleagues¹⁹ found that open RCR was more cost-effective than arthroscopic RCR, with most of the difference attributable to disposables and suture anchors. Genuario and colleagues²¹ found that double-row RCR was not as cost-effective as single-row RCR in treating tears of any size. They attributed the difference to 2 more anchors and about 15 more minutes in the operating room.

The increased interest in healthcare costs and the understanding that a substantial part of the cost of arthroscopic RCR is attributable to implants (suture anchors, specifically) led to recent efforts to eliminate the need for anchors. Newly available instrumentation was designed to assist in arthroscopic anchorless repair constructs using the concepts of traditional TO repair.²² Although still considered to be the RCR gold standard, TO fixation has been used less often in recent years, owing to the shift from open to arthroscopic surgery.²⁴ Arthroscopic TO-RCR allows for all the benefits of arthroscopic surgery, plus the biological and mechanical benefits of traditional open or mini-open TO repair. In addition, this technique eliminates the cost of anchors. Kummer and colleagues²⁵ confirmed with biomechanical testing that arthroscopic TO repair and double-row TOE repair are similar in strength, with a trend of less tendon displacement in the TO group.

Our study results support the hypothesis that arthroscopic TO repair provides significant cost savings over tear size–matched arthroscopic TOE repair. Implant cost was substantially higher for TOE repair than for TO repair. Mean (SD) total savings of $946.91 ($100.70) (P < .0001) can be realized performing TO rather than TOE repair. In the United States, where about 250,000 RCRs are performed each year, the use of TO repair would result in an annual savings of almost $250 million.⁶Operative time was analyzed as well. Running an operating room in the United States costs an estimated $62 per minute (range, $22-$133 per minute).²⁹ Much of this cost is indirect, unrelated to the surgery (eg, capital investment, personnel, insurance), and is being paid even when the operating room is not in use. Therefore, for the hospital’s bottom line, operative time savings are less important than direct cost savings (supplies, implants). However, operative time has more of an effect on the surgeon’s bottom line, and longer procedures reduce the number of surgeries that can be performed and billed. We found no significant difference in operative time between TO and TOE repairs. Critical evaluation revealed that operative time was 5.96 minutes shorter for TOE repairs, but this difference was not significant (P = .677).

Our study results showed no significant difference in clinical outcomes between TO and TOE repair patients. Both groups’ outcome scores improved. At all follow-ups, both groups’ VAS, SANE, and SST scores were significantly improved. Overall, this is the first study to validate the proposed cost benefit of arthroscopic TO repair and confirm no compromise in patient outcomes.

This study had limitations. First, it enrolled relatively few patients, particularly those with small tears. In addition, despite the fact that patients were matched on tear size and concomitant procedures, the groups differed in their biceps pathology treatments. Of the 13 TO patients who had biceps treatment, 12 underwent tenodesis (1 had tenotomy); in contrast, of the 10 TOE patients who had biceps treatment, only 2 underwent tenodesis (8 had tenotomy). The difference is explained by the consecutive course of this study and the increasing popularity of tenodesis over tenotomy. The TOE group underwent surgery before the TO group did, at a time when the involved surgeons were routinely performing tenotomy more than tenodesis. We did not include the costs of implants related to biceps treatment in our analysis, as our focus was on the implant cost of RCR. As for operative time, biceps tenodesis would be expected to extend surgery and potentially affect the comparison of operative times between the TO and TOE groups. However, despite the fact that 12 of the 13 TO patients underwent biceps tenodesis, there was no significant difference in overall operative time. Last, regarding the effect of biceps treatment on clinical outcomes, there are no data showing improved outcomes with tenodesis over tenotomy in the setting of RCR.

A final limitation is lack of data from longer term (>12 months) follow-up for all patients. Our analysis included cost and operative time data for all 42 enrolled patients, but our clinical outcome data represent only 74% of the patients enrolled. Eleven of the 42 patients were lost to follow-up at >12 months, and outcome scores could not be obtained, despite multiple attempts at contact (phone, mail, email). The study design and primary outcome variable focused on cost analysis rather than clinical outcomes. Nevertheless, our data support our hypothesis that there is no difference in clinical outcomes between TO and TOE repairs.

Conclusion

Arthroscopic TO-RCR provides significant cost savings over arthroscopic TOE-RCR without increasing operative time or compromising outcomes. Arthroscopic TO-RCR may have an important role in the evolving healthcare environment and its changing reimbursement models.

Am J Orthop. 2016;45(7):E415-E420. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The rate of medical visits for rotator cuff pathology and the US incidence of arthroscopic rotator cuff repair (RCR) have increased over the past 10 years.¹ The increased use of RCR has been justified with improved patient outcomes.^2,3 Advances in surgical techniques and instrumentation have contributed to better outcomes for patients with rotator cuff pathology.^3-5 Several studies have validated RCR with functional outcome measures, cost–benefit analysis, and health-related quality-of-life measurements.^6-9

Healthcare reimbursement models are being changed to include capitated care, pay for performance, and penalties.¹⁰ Given the changing healthcare climate and the increasing incidence of RCR, it is becoming increasingly important for orthopedic surgeons to critically evaluate and modify their practice and procedures to decrease costs without compromising outcomes.¹¹ RCR outcome studies have focused on comparing open/mini-open with arthroscopic techniques, and single-row with double-row techniques, among others.^4,12-18 Furthermore, several studies on the cost-effectiveness of these surgical techniques have been conducted.^19-21Arthroscopic anchorless (transosseous [TO]) RCR, which is increasingly popular,²² combines the minimal invasiveness of arthroscopic procedures with the biomechanical strength of open TO repair. In addition, this technique avoids the potential complications and costs associated with suture anchors, such as anchor pullout and greater tuberosity osteolysis.^22,23 Several studies have documented the effectiveness of this technique.^24-26 Biomechanical and clinical outcome data supporting arthroscopic TO-RCR have been published, but there are no reports of studies that have analyzed the cost savings associated with this technique.

In this study, we compared implant costs associated with arthroscopic TO-RCR and arthroscopic TO-equivalent (TOE) RCR. We also evaluated these techniques’ operative time and outcomes. Our hypothesis was that arthroscopic TO-RCR can be performed at lower cost and without increasing operative time or compromising outcomes.

Materials and Methods

Our Institutional Review Board approved this study. Between February 2013 and January 2014, participating surgeons performed 43 arthroscopic TO-RCRs that met the study’s inclusion criteria. Twenty-one of the 43 patients enrolled and became the study group. The control group of 21 patients, who underwent arthroscopic TOE-RCR the preceding year (between January 2012 and January 2013), was matched to the study group on tear size and concomitant procedures, including biceps treatment, labral treatment, acromioplasty, and distal clavicle excision (Table 1).

The primary outcome measure was implant cost (amount paid by institution). Cost was determined and reported by an independent third party using Cerner Surginet as the operating room documentation system and McKessen Pathways Materials Management System for item pricing.

All arthroscopic RCRs were performed by 1 of 3 orthopedic surgeons fellowship-trained in either sports medicine or shoulder and elbow surgery. Using the Cofield classification,²⁷ the treating surgeon recorded the size of the rotator cuff tear: small (<1 cm), medium (1-3 cm), large (3-5 cm), massive (>5 cm). The surgeon also recorded the number of suture anchors used, repair technique, biceps treatment, execution of subacromial decompression, execution of distal clavicle excision, and intraoperative complications. TO repair surgical technique is described in the next section. TOE repair was double-row repair with suture anchors. The number of suture anchors varied by tear size: small (3 anchors), medium (2-5 anchors), large (4-6 anchors), massive (4-5 anchors).

Secondary outcome measures were operative time (time from cut to close) and scores on pain VAS (visual analog scale), SANE (Single Assessment Numeric Evaluation), and SST (Simple Shoulder Test). Demographic information was also obtained: age, sex, body mass index, smoking status (Table 1). All patients were asked to fill out questionnaires before surgery and 3, 6, and >12 months after surgery. Outcome surveys were scored by a single research coordinator, who recorded each patient’s outcome scores at the preoperative and postoperative intervals. Follow-up of >12 months was reached by 17 (81%) of the 21 TO patients and 14 (67%) of the 21 TOE patients. For >12 months, the overall rate of follow-up was 74%.

All patients followed the same postoperative rehabilitation protocol: sling immobilization with pendulums for 6 weeks starting at 2 weeks, passive range of motion starting at 6 weeks, and active range of motion starting at 8 weeks. At 3 months, they were allowed progressive resistant exercises with a 10-pound limit, and at 4.5 months they progressed to a 20-pound limit. At 6 months, they were cleared for discharge.

Surgical Technique: Arthroscopic Transosseous Repair

Surgery was performed with the patient in either the beach-chair position or the lateral decubitus position, based on surgeon preference. Our technique is similar to what has been described in the past.^22,28 The glenohumeral joint is accessed through a standard posterior portal, followed by an anterior accessory portal through the rotator interval. Standard diagnostic arthroscopy is performed and intra-articular pathology addressed. Next, the scope is placed in the subacromial space through the posterior portal. A lateral subacromial portal is established and cannulated, and a bursectomy performed. The scope is then placed in a posterolateral portal for better visualization of the rotator cuff tear. The greater tuberosity is débrided with a curette to prepare the bed for repair. An ArthroTunneler (Tornier) is used to pass sutures through the greater tuberosity. For standard 2-tunnel repair, 3 sutures are placed through each tunnel. All 6 sutures are next passed (using a suture passer) through the rotator cuff. The second and fifth suture ends that are passed through the cuff are brought out through the cannula and tied together. They are then brought into the shoulder by pulling on the opposite ends and tied alongside the greater tuberosity to create a box stitch. The box stitch acts as a medial row fixation and as a rip stitch that strengthens the vertical mattress sutures against pullout. The other 4 sutures are tied in vertical mattress configuration.

Statistical Analysis

After obtaining the TO and TOE implant costs, we compared them using a generalized linear model with negative binomial distribution and an identity link function so returned parameters were in additive dollars. This comparison included evaluation of tear size and concomitant procedures. Operative times for TO and TOE were obtained and evaluated, and then compared using time-to-event analysis and the log-rank test. Outcome scores were obtained from patients at baseline and 3, 6, and >12 months after surgery and were compared using a linear mixed model that identified change in outcome scores over time, and difference in outcome scores between the TO and TOE groups.

Results

Table 1 lists patient demographics, including age, sex, body mass index, smoking status, and concomitant procedures. The TO and TOE groups had identical tear-size distributions. In addition, they had similar numbers of concomitant procedures, though our study was underpowered to confirm equivalence. Treatment techniques differed: more biceps tenodesis cases in the TO group (n = 12) than in the TOE group (n = 2) and more biceps tenotomy cases in the TOE group (n = 8) than in the TO group (n = 1).

TO implant cost was significantly lower than TOE implant cost for all tear sizes and independent of concomitant procedures (Figure 1).

Discussion

RCR is one of the most common orthopedic surgical procedures, and its use has increased over the past decade.^9,21 This increase coincides with the emergence of new repair techniques and implants. These advancements come at a cost. Given the increasingly cost-conscious healthcare environment and its changing reimbursement models, now surgeons must evaluate the economics of their surgical procedures in an attempt to decrease costs without compromising outcomes. We hypothesized that arthroscopic TO-RCR can be performed at lower cost relative to arthroscopic TOE-RCR and without increasing operative time or compromising short-term outcomes.

Studies on the cost-effectiveness of different RCR techniques have been conducted.^19-21 Adla and colleagues¹⁹ found that open RCR was more cost-effective than arthroscopic RCR, with most of the difference attributable to disposables and suture anchors. Genuario and colleagues²¹ found that double-row RCR was not as cost-effective as single-row RCR in treating tears of any size. They attributed the difference to 2 more anchors and about 15 more minutes in the operating room.

The increased interest in healthcare costs and the understanding that a substantial part of the cost of arthroscopic RCR is attributable to implants (suture anchors, specifically) led to recent efforts to eliminate the need for anchors. Newly available instrumentation was designed to assist in arthroscopic anchorless repair constructs using the concepts of traditional TO repair.²² Although still considered to be the RCR gold standard, TO fixation has been used less often in recent years, owing to the shift from open to arthroscopic surgery.²⁴ Arthroscopic TO-RCR allows for all the benefits of arthroscopic surgery, plus the biological and mechanical benefits of traditional open or mini-open TO repair. In addition, this technique eliminates the cost of anchors. Kummer and colleagues²⁵ confirmed with biomechanical testing that arthroscopic TO repair and double-row TOE repair are similar in strength, with a trend of less tendon displacement in the TO group.

Our study results support the hypothesis that arthroscopic TO repair provides significant cost savings over tear size–matched arthroscopic TOE repair. Implant cost was substantially higher for TOE repair than for TO repair. Mean (SD) total savings of $946.91 ($100.70) (P < .0001) can be realized performing TO rather than TOE repair. In the United States, where about 250,000 RCRs are performed each year, the use of TO repair would result in an annual savings of almost $250 million.⁶Operative time was analyzed as well. Running an operating room in the United States costs an estimated $62 per minute (range, $22-$133 per minute).²⁹ Much of this cost is indirect, unrelated to the surgery (eg, capital investment, personnel, insurance), and is being paid even when the operating room is not in use. Therefore, for the hospital’s bottom line, operative time savings are less important than direct cost savings (supplies, implants). However, operative time has more of an effect on the surgeon’s bottom line, and longer procedures reduce the number of surgeries that can be performed and billed. We found no significant difference in operative time between TO and TOE repairs. Critical evaluation revealed that operative time was 5.96 minutes shorter for TOE repairs, but this difference was not significant (P = .677).

Our study results showed no significant difference in clinical outcomes between TO and TOE repair patients. Both groups’ outcome scores improved. At all follow-ups, both groups’ VAS, SANE, and SST scores were significantly improved. Overall, this is the first study to validate the proposed cost benefit of arthroscopic TO repair and confirm no compromise in patient outcomes.

This study had limitations. First, it enrolled relatively few patients, particularly those with small tears. In addition, despite the fact that patients were matched on tear size and concomitant procedures, the groups differed in their biceps pathology treatments. Of the 13 TO patients who had biceps treatment, 12 underwent tenodesis (1 had tenotomy); in contrast, of the 10 TOE patients who had biceps treatment, only 2 underwent tenodesis (8 had tenotomy). The difference is explained by the consecutive course of this study and the increasing popularity of tenodesis over tenotomy. The TOE group underwent surgery before the TO group did, at a time when the involved surgeons were routinely performing tenotomy more than tenodesis. We did not include the costs of implants related to biceps treatment in our analysis, as our focus was on the implant cost of RCR. As for operative time, biceps tenodesis would be expected to extend surgery and potentially affect the comparison of operative times between the TO and TOE groups. However, despite the fact that 12 of the 13 TO patients underwent biceps tenodesis, there was no significant difference in overall operative time. Last, regarding the effect of biceps treatment on clinical outcomes, there are no data showing improved outcomes with tenodesis over tenotomy in the setting of RCR.

A final limitation is lack of data from longer term (>12 months) follow-up for all patients. Our analysis included cost and operative time data for all 42 enrolled patients, but our clinical outcome data represent only 74% of the patients enrolled. Eleven of the 42 patients were lost to follow-up at >12 months, and outcome scores could not be obtained, despite multiple attempts at contact (phone, mail, email). The study design and primary outcome variable focused on cost analysis rather than clinical outcomes. Nevertheless, our data support our hypothesis that there is no difference in clinical outcomes between TO and TOE repairs.

Conclusion

Arthroscopic TO-RCR provides significant cost savings over arthroscopic TOE-RCR without increasing operative time or compromising outcomes. Arthroscopic TO-RCR may have an important role in the evolving healthcare environment and its changing reimbursement models.

Am J Orthop. 2016;45(7):E415-E420. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The rate of medical visits for rotator cuff pathology and the US incidence of arthroscopic rotator cuff repair (RCR) have increased over the past 10 years.¹ The increased use of RCR has been justified with improved patient outcomes.^2,3 Advances in surgical techniques and instrumentation have contributed to better outcomes for patients with rotator cuff pathology.^3-5 Several studies have validated RCR with functional outcome measures, cost–benefit analysis, and health-related quality-of-life measurements.^6-9

Healthcare reimbursement models are being changed to include capitated care, pay for performance, and penalties.¹⁰ Given the changing healthcare climate and the increasing incidence of RCR, it is becoming increasingly important for orthopedic surgeons to critically evaluate and modify their practice and procedures to decrease costs without compromising outcomes.¹¹ RCR outcome studies have focused on comparing open/mini-open with arthroscopic techniques, and single-row with double-row techniques, among others.^4,12-18 Furthermore, several studies on the cost-effectiveness of these surgical techniques have been conducted.^19-21Arthroscopic anchorless (transosseous [TO]) RCR, which is increasingly popular,²² combines the minimal invasiveness of arthroscopic procedures with the biomechanical strength of open TO repair. In addition, this technique avoids the potential complications and costs associated with suture anchors, such as anchor pullout and greater tuberosity osteolysis.^22,23 Several studies have documented the effectiveness of this technique.^24-26 Biomechanical and clinical outcome data supporting arthroscopic TO-RCR have been published, but there are no reports of studies that have analyzed the cost savings associated with this technique.

In this study, we compared implant costs associated with arthroscopic TO-RCR and arthroscopic TO-equivalent (TOE) RCR. We also evaluated these techniques’ operative time and outcomes. Our hypothesis was that arthroscopic TO-RCR can be performed at lower cost and without increasing operative time or compromising outcomes.

Materials and Methods

Our Institutional Review Board approved this study. Between February 2013 and January 2014, participating surgeons performed 43 arthroscopic TO-RCRs that met the study’s inclusion criteria. Twenty-one of the 43 patients enrolled and became the study group. The control group of 21 patients, who underwent arthroscopic TOE-RCR the preceding year (between January 2012 and January 2013), was matched to the study group on tear size and concomitant procedures, including biceps treatment, labral treatment, acromioplasty, and distal clavicle excision (Table 1).

The primary outcome measure was implant cost (amount paid by institution). Cost was determined and reported by an independent third party using Cerner Surginet as the operating room documentation system and McKessen Pathways Materials Management System for item pricing.

All arthroscopic RCRs were performed by 1 of 3 orthopedic surgeons fellowship-trained in either sports medicine or shoulder and elbow surgery. Using the Cofield classification,²⁷ the treating surgeon recorded the size of the rotator cuff tear: small (<1 cm), medium (1-3 cm), large (3-5 cm), massive (>5 cm). The surgeon also recorded the number of suture anchors used, repair technique, biceps treatment, execution of subacromial decompression, execution of distal clavicle excision, and intraoperative complications. TO repair surgical technique is described in the next section. TOE repair was double-row repair with suture anchors. The number of suture anchors varied by tear size: small (3 anchors), medium (2-5 anchors), large (4-6 anchors), massive (4-5 anchors).

Secondary outcome measures were operative time (time from cut to close) and scores on pain VAS (visual analog scale), SANE (Single Assessment Numeric Evaluation), and SST (Simple Shoulder Test). Demographic information was also obtained: age, sex, body mass index, smoking status (Table 1). All patients were asked to fill out questionnaires before surgery and 3, 6, and >12 months after surgery. Outcome surveys were scored by a single research coordinator, who recorded each patient’s outcome scores at the preoperative and postoperative intervals. Follow-up of >12 months was reached by 17 (81%) of the 21 TO patients and 14 (67%) of the 21 TOE patients. For >12 months, the overall rate of follow-up was 74%.

All patients followed the same postoperative rehabilitation protocol: sling immobilization with pendulums for 6 weeks starting at 2 weeks, passive range of motion starting at 6 weeks, and active range of motion starting at 8 weeks. At 3 months, they were allowed progressive resistant exercises with a 10-pound limit, and at 4.5 months they progressed to a 20-pound limit. At 6 months, they were cleared for discharge.

Surgical Technique: Arthroscopic Transosseous Repair

Surgery was performed with the patient in either the beach-chair position or the lateral decubitus position, based on surgeon preference. Our technique is similar to what has been described in the past.^22,28 The glenohumeral joint is accessed through a standard posterior portal, followed by an anterior accessory portal through the rotator interval. Standard diagnostic arthroscopy is performed and intra-articular pathology addressed. Next, the scope is placed in the subacromial space through the posterior portal. A lateral subacromial portal is established and cannulated, and a bursectomy performed. The scope is then placed in a posterolateral portal for better visualization of the rotator cuff tear. The greater tuberosity is débrided with a curette to prepare the bed for repair. An ArthroTunneler (Tornier) is used to pass sutures through the greater tuberosity. For standard 2-tunnel repair, 3 sutures are placed through each tunnel. All 6 sutures are next passed (using a suture passer) through the rotator cuff. The second and fifth suture ends that are passed through the cuff are brought out through the cannula and tied together. They are then brought into the shoulder by pulling on the opposite ends and tied alongside the greater tuberosity to create a box stitch. The box stitch acts as a medial row fixation and as a rip stitch that strengthens the vertical mattress sutures against pullout. The other 4 sutures are tied in vertical mattress configuration.

Statistical Analysis

After obtaining the TO and TOE implant costs, we compared them using a generalized linear model with negative binomial distribution and an identity link function so returned parameters were in additive dollars. This comparison included evaluation of tear size and concomitant procedures. Operative times for TO and TOE were obtained and evaluated, and then compared using time-to-event analysis and the log-rank test. Outcome scores were obtained from patients at baseline and 3, 6, and >12 months after surgery and were compared using a linear mixed model that identified change in outcome scores over time, and difference in outcome scores between the TO and TOE groups.

Results

Table 1 lists patient demographics, including age, sex, body mass index, smoking status, and concomitant procedures. The TO and TOE groups had identical tear-size distributions. In addition, they had similar numbers of concomitant procedures, though our study was underpowered to confirm equivalence. Treatment techniques differed: more biceps tenodesis cases in the TO group (n = 12) than in the TOE group (n = 2) and more biceps tenotomy cases in the TOE group (n = 8) than in the TO group (n = 1).

TO implant cost was significantly lower than TOE implant cost for all tear sizes and independent of concomitant procedures (Figure 1).

Discussion

RCR is one of the most common orthopedic surgical procedures, and its use has increased over the past decade.^9,21 This increase coincides with the emergence of new repair techniques and implants. These advancements come at a cost. Given the increasingly cost-conscious healthcare environment and its changing reimbursement models, now surgeons must evaluate the economics of their surgical procedures in an attempt to decrease costs without compromising outcomes. We hypothesized that arthroscopic TO-RCR can be performed at lower cost relative to arthroscopic TOE-RCR and without increasing operative time or compromising short-term outcomes.

Studies on the cost-effectiveness of different RCR techniques have been conducted.^19-21 Adla and colleagues¹⁹ found that open RCR was more cost-effective than arthroscopic RCR, with most of the difference attributable to disposables and suture anchors. Genuario and colleagues²¹ found that double-row RCR was not as cost-effective as single-row RCR in treating tears of any size. They attributed the difference to 2 more anchors and about 15 more minutes in the operating room.

The increased interest in healthcare costs and the understanding that a substantial part of the cost of arthroscopic RCR is attributable to implants (suture anchors, specifically) led to recent efforts to eliminate the need for anchors. Newly available instrumentation was designed to assist in arthroscopic anchorless repair constructs using the concepts of traditional TO repair.²² Although still considered to be the RCR gold standard, TO fixation has been used less often in recent years, owing to the shift from open to arthroscopic surgery.²⁴ Arthroscopic TO-RCR allows for all the benefits of arthroscopic surgery, plus the biological and mechanical benefits of traditional open or mini-open TO repair. In addition, this technique eliminates the cost of anchors. Kummer and colleagues²⁵ confirmed with biomechanical testing that arthroscopic TO repair and double-row TOE repair are similar in strength, with a trend of less tendon displacement in the TO group.

Our study results support the hypothesis that arthroscopic TO repair provides significant cost savings over tear size–matched arthroscopic TOE repair. Implant cost was substantially higher for TOE repair than for TO repair. Mean (SD) total savings of $946.91 ($100.70) (P < .0001) can be realized performing TO rather than TOE repair. In the United States, where about 250,000 RCRs are performed each year, the use of TO repair would result in an annual savings of almost $250 million.⁶Operative time was analyzed as well. Running an operating room in the United States costs an estimated $62 per minute (range, $22-$133 per minute).²⁹ Much of this cost is indirect, unrelated to the surgery (eg, capital investment, personnel, insurance), and is being paid even when the operating room is not in use. Therefore, for the hospital’s bottom line, operative time savings are less important than direct cost savings (supplies, implants). However, operative time has more of an effect on the surgeon’s bottom line, and longer procedures reduce the number of surgeries that can be performed and billed. We found no significant difference in operative time between TO and TOE repairs. Critical evaluation revealed that operative time was 5.96 minutes shorter for TOE repairs, but this difference was not significant (P = .677).

Our study results showed no significant difference in clinical outcomes between TO and TOE repair patients. Both groups’ outcome scores improved. At all follow-ups, both groups’ VAS, SANE, and SST scores were significantly improved. Overall, this is the first study to validate the proposed cost benefit of arthroscopic TO repair and confirm no compromise in patient outcomes.

This study had limitations. First, it enrolled relatively few patients, particularly those with small tears. In addition, despite the fact that patients were matched on tear size and concomitant procedures, the groups differed in their biceps pathology treatments. Of the 13 TO patients who had biceps treatment, 12 underwent tenodesis (1 had tenotomy); in contrast, of the 10 TOE patients who had biceps treatment, only 2 underwent tenodesis (8 had tenotomy). The difference is explained by the consecutive course of this study and the increasing popularity of tenodesis over tenotomy. The TOE group underwent surgery before the TO group did, at a time when the involved surgeons were routinely performing tenotomy more than tenodesis. We did not include the costs of implants related to biceps treatment in our analysis, as our focus was on the implant cost of RCR. As for operative time, biceps tenodesis would be expected to extend surgery and potentially affect the comparison of operative times between the TO and TOE groups. However, despite the fact that 12 of the 13 TO patients underwent biceps tenodesis, there was no significant difference in overall operative time. Last, regarding the effect of biceps treatment on clinical outcomes, there are no data showing improved outcomes with tenodesis over tenotomy in the setting of RCR.

A final limitation is lack of data from longer term (>12 months) follow-up for all patients. Our analysis included cost and operative time data for all 42 enrolled patients, but our clinical outcome data represent only 74% of the patients enrolled. Eleven of the 42 patients were lost to follow-up at >12 months, and outcome scores could not be obtained, despite multiple attempts at contact (phone, mail, email). The study design and primary outcome variable focused on cost analysis rather than clinical outcomes. Nevertheless, our data support our hypothesis that there is no difference in clinical outcomes between TO and TOE repairs.

Conclusion

Arthroscopic TO-RCR provides significant cost savings over arthroscopic TOE-RCR without increasing operative time or compromising outcomes. Arthroscopic TO-RCR may have an important role in the evolving healthcare environment and its changing reimbursement models.

Am J Orthop. 2016;45(7):E415-E420. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

WASHINGTON – The perioperative use of disease-modifying antirheumatic drug monotherapy or combined therapy with methotrexate and a tumor necrosis factor (TNF) inhibitor is not associated with increased rates of postoperative infectious complications or wound infections in patients with rheumatoid arthritis, according to findings from a retrospective review of more than 9,000 surgeries.

With respect to monotherapy, treatment was continued in 1,951 of 2,601 surgeries among patients receiving methotrexate, in 1,496 of 2,012 surgeries among patients receiving hydroxychloroquine, and in 508 of 652 surgeries among patient receiving leflunomide. The odds ratios for postoperative infection (including urinary tract, pneumonia, or sepsis) and postoperative wound infection, respectively, were 0.79 and 0.77 with methotrexate continuation, 0.93 and 0.86 with hydroxychloroquine continuation, and 0.78 and 0.87 with leflunomide continuation, Hsin-Hsuan Juo, MD, reported at the annual meeting of the American College of Rheumatology.

Dmitrii Kotin/Thinkstock

sworcester@frontlinemedcom.com

WASHINGTON – The perioperative use of disease-modifying antirheumatic drug monotherapy or combined therapy with methotrexate and a tumor necrosis factor (TNF) inhibitor is not associated with increased rates of postoperative infectious complications or wound infections in patients with rheumatoid arthritis, according to findings from a retrospective review of more than 9,000 surgeries.

With respect to monotherapy, treatment was continued in 1,951 of 2,601 surgeries among patients receiving methotrexate, in 1,496 of 2,012 surgeries among patients receiving hydroxychloroquine, and in 508 of 652 surgeries among patient receiving leflunomide. The odds ratios for postoperative infection (including urinary tract, pneumonia, or sepsis) and postoperative wound infection, respectively, were 0.79 and 0.77 with methotrexate continuation, 0.93 and 0.86 with hydroxychloroquine continuation, and 0.78 and 0.87 with leflunomide continuation, Hsin-Hsuan Juo, MD, reported at the annual meeting of the American College of Rheumatology.

Dmitrii Kotin/Thinkstock

sworcester@frontlinemedcom.com

WASHINGTON – The perioperative use of disease-modifying antirheumatic drug monotherapy or combined therapy with methotrexate and a tumor necrosis factor (TNF) inhibitor is not associated with increased rates of postoperative infectious complications or wound infections in patients with rheumatoid arthritis, according to findings from a retrospective review of more than 9,000 surgeries.

With respect to monotherapy, treatment was continued in 1,951 of 2,601 surgeries among patients receiving methotrexate, in 1,496 of 2,012 surgeries among patients receiving hydroxychloroquine, and in 508 of 652 surgeries among patient receiving leflunomide. The odds ratios for postoperative infection (including urinary tract, pneumonia, or sepsis) and postoperative wound infection, respectively, were 0.79 and 0.77 with methotrexate continuation, 0.93 and 0.86 with hydroxychloroquine continuation, and 0.78 and 0.87 with leflunomide continuation, Hsin-Hsuan Juo, MD, reported at the annual meeting of the American College of Rheumatology.

Dmitrii Kotin/Thinkstock

sworcester@frontlinemedcom.com

The amniotic membrane is a multilayer tissue forming the innermost layer of the amniotic sac that surrounds the developing fetus. It is comprised of 5 layers, from the inside out: a single layer of epithelial cells, a thick basement membrane, a compact layer, a fibroblast layer, and a spongy layer that abuts the surrounding chorion (Figure 1).¹

Amniotic epithelial cells are derived from the pluripotent epiblast at approximately day 8 of gestation. This is well before gastrulation occurs at days 15 to 17, considered the “tipping point” when pluripotent cells differentiate into ectoderm, mesoderm, and endoderm.³ These cells express Oct-4 and Nanog, 2 molecular markers that are indicative of pluripotency.³ Two cell types have been identified in amniotic tissues that possess stem cell-like characteristics: human amniotic epithelial cells and human amniotic mesenchymal stromal cells.⁴ Both of these cell types have demonstrated the ability to differentiate into various cell lineages, including endothelial cells, adipocytes, myogenic cells, neurogenic cells, chondrocytes, tenocytes, and osteogenic cells.^5-7 These previously reported findings indicate that amniotic cells and tissue have the capability to generate mesenchymal tissues.

FDA Classification and Available Forms

The US Food and Drug Administration (FDA) classifies amnion as an allograft tissue under Human Cells, Tissues, and Cellular and Tissue-Based Products (HCT/Ps) 361. To meet criteria, the tissue needs to be minimally manipulated. It is to be for homologous use and cannot be combined with other cells or tissues. There can be no systemic effect or dependence on the metabolic activity of living cells to achieve its primary function. The tissue has to have a localized effect in vivo. Therefore, amnion allograft tissue can be commercialized, provided it is not marketed as a stem cell product or to contain viable cells.

Amniotic tissue is commercially available in several forms.

Safety

Amniotic tissue has been used for over 100 years in burn, ophthalmology, and chronic wound patients with favorable outcomes and no adverse effects reported in the literature. Unlike embryonic stem cells, which may be tumorigenic,⁸ amniotic cells do not possess any known tumorigenicity.⁹ In one study, 50 immunodeficient mice were injected with 1 to 2 million amniotic epithelial cells and observed for a maximum of 516 days with no tumorigenicity observed in any of the animals.¹⁰ In another study, amniotic epithelial cells were implanted into the forearms of healthy volunteers and no immunologic response was observed in any of the recipients.¹¹ Furthermore, viable amniotic cells were recovered via biopsy 7 weeks following transplantation, demonstrating viability of the transplanted cells.¹¹ The lack of tumorigenicity and immunologic response in hosts is due in part to the fact that amniotic cells do not express human leukocyte antigen class II antigens and only express class I antigens in small amounts.³

Advantages of Amnion Tissue

Amniotic tissue is readily available, as it is often discarded after childbirth. The use of this tissue poses no added risk to the fetus or mother, eliminating the ethical concerns associated with obtaining embryonic stem cells. Amniotic tissue is comprised of an extracellular matrix, which acts as a natural scaffold for cellular attachment and structural support for cells as well as collagen types I, III, IV, V, and VI, hyaluronic acid, and a host of growth factors.¹² In addition, it possesses antimicrobial properties, including beta-defensins.¹³

Amniotic tissue has been shown to exert an anti-inflammatory effect by inhibiting the inflammatory cascade. Specifically, it has been shown to inhibit cytokines such as tumor necrosis factor-alpha in the presence of dendritic cells,¹⁴ as well as inhibiting transforming growth factor-beta, interleukin-8, and fibroblast proliferation.¹⁵ These findings indicate that amniotic tissue has the ability to dampen the “cytokine storm” that occurs after an injury in an adult, which would lead to beneficial impacts on healing and scar formation in patients.¹⁶

Basic Science and Animal Studies

Several studies have demonstrated promising outcomes for orthopedic applications in vitro. A comparison of osteogenic potential found that amniotic fluid-derived cells were able to produce approximately 5 times more mineralized matrix than bone marrow-derived mesenchymal stem cells.¹⁷ More recently, Si and colleagues¹⁸ compared the osteogenic potential of human amniotic epithelial cells, amniotic cells, and human bone marrow-derived mesenchymal stem cells. They found that all 3 cell lines were osteogenic, though the amniotic epithelial cells had better immunomodulatory properties and marginally less osteogenic potential than the other 2 cell types. Furthermore, several in vivo animal studies have demonstrated the ability of human amniotic cells to stimulate bone growth in rats,^19,20 rabbits,²¹ and sheep.²²

Amniotic tissue also possesses potential for chondrogenesis. Cryopreserved human amniotic membrane cells used for in vitro human osteoarthritis tissue scaffolds did not differentiate in culture, and they integrated and repaired damaged articular cartilage.²³ Various in vitro^24,25 and animal in vivo^26,27 studies have reported similar supportive findings. Kunisaki and colleagues²⁸ used sheep amniotic fluid mesenchymal stem cells to reconstruct lamb tracheal cartilage in utero, concluding that cells obtained from the amniotic fluid possess chondrogenic capabilities. Further in utero lamb studies of cartilage artificial defects, given 7 days to settle before adding a hypocellular matrix as a scaffold, showed chondrocyte density and cell architecture was restored at the defect site after 28 days without the formation of an inflammatory response or scar tissue.²⁹

Amniotic tissue has had similar success in tendon repair studies in vivo.^9,30,31 Barboni and colleagues³² implanted amniotic epithelial cells (AECs) into artificially created sheep Achilles tendon defects in situ, inducing superior structural and mechanical recovery in the defects at a faster rate compared to controls not receiving AECs. Healing via AECs started at the healthy tissue around the borders of the defect and progressed centrally, suggesting recruitment of native progenitor cells to the lesion.³² Kueckelhaus and colleagues³³ investigated the role of amnion-derived cellular cytokine solution in the healing of transections of rat Achilles tendons, reporting improved mechanical properties of healing tendons at early time points compared to controls. Beredjiklian and colleagues³⁴ compared the healing of transected extensor tendons of pregnant ewes and of their fetus in utero, reporting a reparative form of healing with scar formation in adult subjects and regenerative form of healing without scar formation or inflammation in fetal subjects.

Amniotic tissue has properties that prevent adhesion formation around tendons following injury and reconstruction.³⁵ Ozgenel³⁶ investigated the effects of hyaluronic acid and amniotic membrane alone and in combination on the presence of adhesions and the rate of healing following chicken flexor tendon repair. The study found amniotic membrane wrapped around the repaired tendon was superior in preventing adhesion formation. Kim and colleagues³⁷ report a similar reduction in fibrosis and adhesion following application of a human amniotic membrane wrap to rabbit ulnar neurorrhaphy sites.

This barrier function of amniotic tissue has also been investigated in the prevention of surgical scarring and peridural fibrosis in animal models following spinal discectomy. A study in canine models showed a reduction of scarring following the application of cross-linked amniotic membrane compared to freeze dried amniotic membrane.³⁸ Similar reductions in scarring in rat models with the application of freeze-dried amniotic membrane compared to negative controls have been reported.³⁹

Human Studies

A randomized trial investigated the outcomes of prenatal vs postnatal repair of myelomeningocele in humans, finding a reduced need for implanted shunts and improved functional outcomes at 30 months of life in the prenatal intervention group compared to the postnatal group.⁴⁰ This study was concluded early due to the efficacy of prenatal surgery and the benefit of nervous system repair in utero in the presence of amniotic growth factors.

Vines and colleagues⁴¹ performed a 6-patient feasibility study using amnion injections to treat symptomatic knee osteoarthritis. Each patient received a single intra-articular cryopreserved amniotic suspension allograft (ASA) injection and was followed for 1 year. No adverse outcomes were reported, with the only abnormal finding being a small increase in serum immunoglobulin G and immunoglobulin E levels. Intra-articular ASA injection was found to be safe, but a large-scale trial investigating symptomatic relief was recommended.⁴¹

Most of the human studies using amnion pertain to foot and ankle surgery. Its use as a treatment for diabetic foot ulcers and recalcitrant plantar fasciitis was one of the early-recognized successes.^42-45 Zelen and colleagues⁴⁶ investigated the applications of injectable micronized dehydrated human amniotic/chorionic membrane as an alternative to surgical intervention in the treatment of refractory plantar fasciitis. This prospective, randomized trial with 45 patients showed significant improvement in plantar fasciitis symptoms at 8 weeks compared to controls (saline injections). A similar study compared the use of cryopreserved human amniotic membrane (c-hAM) injections to corticosteroid injections in plantar fasciitis patients.⁴⁷ The results indicated that c-hAM is safe and comparable to corticosteroids, with the authors noting that pain improvement was greatest in patients receiving 2 injections of c-hAM at 18 weeks.

Tendon wrapping, in which the amniotic membrane is laid over a tendon repair, has been reported with success. Amniotic membrane is superior to collagen for tendon wrapping as it actively contributes to healing while minimizing adhesions, which collagen alone cannot do.⁴⁸ The membrane serves as a protective sheath around repaired tendons with anti-inflammatory, anti-adhesive, immunomodulatory, and antimicrobial benefits. A 124-patient study demonstrated the safety of using amnion in this manner, and the authors reported a decreased rate of complication compared to previously published data.⁴⁹ Another study of 14 patients undergoing foot and ankle surgery with tendon wrapping reported clinical improvement with reduced pain and greater functional outcomes postoperatively compared to preoperative measurements.⁵⁰

Conclusion

Amniotic membrane-derived tissues are safe and non-tumorigenic, producing an abundance of growth factors that have shown promise as tissue scaffolds and as aids in the regeneration of human bone and soft tissues. Amnion applications in orthopedic surgery may be numerous, but development is ongoing. Given the vast array of in vitro and in vivo animal data supporting the benefits of amnion in tissue regeneration, orthopedic surgeons and researchers should place emphasis on conducting clinical studies to validate the safety and efficacy of amniotic cells in the treatment of orthopedic conditions.

Am J Orthop. 2016;45(7):E421-E425. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The amniotic membrane is a multilayer tissue forming the innermost layer of the amniotic sac that surrounds the developing fetus. It is comprised of 5 layers, from the inside out: a single layer of epithelial cells, a thick basement membrane, a compact layer, a fibroblast layer, and a spongy layer that abuts the surrounding chorion (Figure 1).¹

Amniotic epithelial cells are derived from the pluripotent epiblast at approximately day 8 of gestation. This is well before gastrulation occurs at days 15 to 17, considered the “tipping point” when pluripotent cells differentiate into ectoderm, mesoderm, and endoderm.³ These cells express Oct-4 and Nanog, 2 molecular markers that are indicative of pluripotency.³ Two cell types have been identified in amniotic tissues that possess stem cell-like characteristics: human amniotic epithelial cells and human amniotic mesenchymal stromal cells.⁴ Both of these cell types have demonstrated the ability to differentiate into various cell lineages, including endothelial cells, adipocytes, myogenic cells, neurogenic cells, chondrocytes, tenocytes, and osteogenic cells.^5-7 These previously reported findings indicate that amniotic cells and tissue have the capability to generate mesenchymal tissues.

FDA Classification and Available Forms

The US Food and Drug Administration (FDA) classifies amnion as an allograft tissue under Human Cells, Tissues, and Cellular and Tissue-Based Products (HCT/Ps) 361. To meet criteria, the tissue needs to be minimally manipulated. It is to be for homologous use and cannot be combined with other cells or tissues. There can be no systemic effect or dependence on the metabolic activity of living cells to achieve its primary function. The tissue has to have a localized effect in vivo. Therefore, amnion allograft tissue can be commercialized, provided it is not marketed as a stem cell product or to contain viable cells.

Amniotic tissue is commercially available in several forms.

Safety

Amniotic tissue has been used for over 100 years in burn, ophthalmology, and chronic wound patients with favorable outcomes and no adverse effects reported in the literature. Unlike embryonic stem cells, which may be tumorigenic,⁸ amniotic cells do not possess any known tumorigenicity.⁹ In one study, 50 immunodeficient mice were injected with 1 to 2 million amniotic epithelial cells and observed for a maximum of 516 days with no tumorigenicity observed in any of the animals.¹⁰ In another study, amniotic epithelial cells were implanted into the forearms of healthy volunteers and no immunologic response was observed in any of the recipients.¹¹ Furthermore, viable amniotic cells were recovered via biopsy 7 weeks following transplantation, demonstrating viability of the transplanted cells.¹¹ The lack of tumorigenicity and immunologic response in hosts is due in part to the fact that amniotic cells do not express human leukocyte antigen class II antigens and only express class I antigens in small amounts.³

Advantages of Amnion Tissue

Amniotic tissue is readily available, as it is often discarded after childbirth. The use of this tissue poses no added risk to the fetus or mother, eliminating the ethical concerns associated with obtaining embryonic stem cells. Amniotic tissue is comprised of an extracellular matrix, which acts as a natural scaffold for cellular attachment and structural support for cells as well as collagen types I, III, IV, V, and VI, hyaluronic acid, and a host of growth factors.¹² In addition, it possesses antimicrobial properties, including beta-defensins.¹³

Amniotic tissue has been shown to exert an anti-inflammatory effect by inhibiting the inflammatory cascade. Specifically, it has been shown to inhibit cytokines such as tumor necrosis factor-alpha in the presence of dendritic cells,¹⁴ as well as inhibiting transforming growth factor-beta, interleukin-8, and fibroblast proliferation.¹⁵ These findings indicate that amniotic tissue has the ability to dampen the “cytokine storm” that occurs after an injury in an adult, which would lead to beneficial impacts on healing and scar formation in patients.¹⁶

Basic Science and Animal Studies

Several studies have demonstrated promising outcomes for orthopedic applications in vitro. A comparison of osteogenic potential found that amniotic fluid-derived cells were able to produce approximately 5 times more mineralized matrix than bone marrow-derived mesenchymal stem cells.¹⁷ More recently, Si and colleagues¹⁸ compared the osteogenic potential of human amniotic epithelial cells, amniotic cells, and human bone marrow-derived mesenchymal stem cells. They found that all 3 cell lines were osteogenic, though the amniotic epithelial cells had better immunomodulatory properties and marginally less osteogenic potential than the other 2 cell types. Furthermore, several in vivo animal studies have demonstrated the ability of human amniotic cells to stimulate bone growth in rats,^19,20 rabbits,²¹ and sheep.²²

Amniotic tissue also possesses potential for chondrogenesis. Cryopreserved human amniotic membrane cells used for in vitro human osteoarthritis tissue scaffolds did not differentiate in culture, and they integrated and repaired damaged articular cartilage.²³ Various in vitro^24,25 and animal in vivo^26,27 studies have reported similar supportive findings. Kunisaki and colleagues²⁸ used sheep amniotic fluid mesenchymal stem cells to reconstruct lamb tracheal cartilage in utero, concluding that cells obtained from the amniotic fluid possess chondrogenic capabilities. Further in utero lamb studies of cartilage artificial defects, given 7 days to settle before adding a hypocellular matrix as a scaffold, showed chondrocyte density and cell architecture was restored at the defect site after 28 days without the formation of an inflammatory response or scar tissue.²⁹

Amniotic tissue has had similar success in tendon repair studies in vivo.^9,30,31 Barboni and colleagues³² implanted amniotic epithelial cells (AECs) into artificially created sheep Achilles tendon defects in situ, inducing superior structural and mechanical recovery in the defects at a faster rate compared to controls not receiving AECs. Healing via AECs started at the healthy tissue around the borders of the defect and progressed centrally, suggesting recruitment of native progenitor cells to the lesion.³² Kueckelhaus and colleagues³³ investigated the role of amnion-derived cellular cytokine solution in the healing of transections of rat Achilles tendons, reporting improved mechanical properties of healing tendons at early time points compared to controls. Beredjiklian and colleagues³⁴ compared the healing of transected extensor tendons of pregnant ewes and of their fetus in utero, reporting a reparative form of healing with scar formation in adult subjects and regenerative form of healing without scar formation or inflammation in fetal subjects.

Amniotic tissue has properties that prevent adhesion formation around tendons following injury and reconstruction.³⁵ Ozgenel³⁶ investigated the effects of hyaluronic acid and amniotic membrane alone and in combination on the presence of adhesions and the rate of healing following chicken flexor tendon repair. The study found amniotic membrane wrapped around the repaired tendon was superior in preventing adhesion formation. Kim and colleagues³⁷ report a similar reduction in fibrosis and adhesion following application of a human amniotic membrane wrap to rabbit ulnar neurorrhaphy sites.

This barrier function of amniotic tissue has also been investigated in the prevention of surgical scarring and peridural fibrosis in animal models following spinal discectomy. A study in canine models showed a reduction of scarring following the application of cross-linked amniotic membrane compared to freeze dried amniotic membrane.³⁸ Similar reductions in scarring in rat models with the application of freeze-dried amniotic membrane compared to negative controls have been reported.³⁹

Human Studies

A randomized trial investigated the outcomes of prenatal vs postnatal repair of myelomeningocele in humans, finding a reduced need for implanted shunts and improved functional outcomes at 30 months of life in the prenatal intervention group compared to the postnatal group.⁴⁰ This study was concluded early due to the efficacy of prenatal surgery and the benefit of nervous system repair in utero in the presence of amniotic growth factors.

Vines and colleagues⁴¹ performed a 6-patient feasibility study using amnion injections to treat symptomatic knee osteoarthritis. Each patient received a single intra-articular cryopreserved amniotic suspension allograft (ASA) injection and was followed for 1 year. No adverse outcomes were reported, with the only abnormal finding being a small increase in serum immunoglobulin G and immunoglobulin E levels. Intra-articular ASA injection was found to be safe, but a large-scale trial investigating symptomatic relief was recommended.⁴¹

Most of the human studies using amnion pertain to foot and ankle surgery. Its use as a treatment for diabetic foot ulcers and recalcitrant plantar fasciitis was one of the early-recognized successes.^42-45 Zelen and colleagues⁴⁶ investigated the applications of injectable micronized dehydrated human amniotic/chorionic membrane as an alternative to surgical intervention in the treatment of refractory plantar fasciitis. This prospective, randomized trial with 45 patients showed significant improvement in plantar fasciitis symptoms at 8 weeks compared to controls (saline injections). A similar study compared the use of cryopreserved human amniotic membrane (c-hAM) injections to corticosteroid injections in plantar fasciitis patients.⁴⁷ The results indicated that c-hAM is safe and comparable to corticosteroids, with the authors noting that pain improvement was greatest in patients receiving 2 injections of c-hAM at 18 weeks.

Tendon wrapping, in which the amniotic membrane is laid over a tendon repair, has been reported with success. Amniotic membrane is superior to collagen for tendon wrapping as it actively contributes to healing while minimizing adhesions, which collagen alone cannot do.⁴⁸ The membrane serves as a protective sheath around repaired tendons with anti-inflammatory, anti-adhesive, immunomodulatory, and antimicrobial benefits. A 124-patient study demonstrated the safety of using amnion in this manner, and the authors reported a decreased rate of complication compared to previously published data.⁴⁹ Another study of 14 patients undergoing foot and ankle surgery with tendon wrapping reported clinical improvement with reduced pain and greater functional outcomes postoperatively compared to preoperative measurements.⁵⁰

Conclusion

Amniotic membrane-derived tissues are safe and non-tumorigenic, producing an abundance of growth factors that have shown promise as tissue scaffolds and as aids in the regeneration of human bone and soft tissues. Amnion applications in orthopedic surgery may be numerous, but development is ongoing. Given the vast array of in vitro and in vivo animal data supporting the benefits of amnion in tissue regeneration, orthopedic surgeons and researchers should place emphasis on conducting clinical studies to validate the safety and efficacy of amniotic cells in the treatment of orthopedic conditions.

Am J Orthop. 2016;45(7):E421-E425. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The amniotic membrane is a multilayer tissue forming the innermost layer of the amniotic sac that surrounds the developing fetus. It is comprised of 5 layers, from the inside out: a single layer of epithelial cells, a thick basement membrane, a compact layer, a fibroblast layer, and a spongy layer that abuts the surrounding chorion (Figure 1).¹

Amniotic epithelial cells are derived from the pluripotent epiblast at approximately day 8 of gestation. This is well before gastrulation occurs at days 15 to 17, considered the “tipping point” when pluripotent cells differentiate into ectoderm, mesoderm, and endoderm.³ These cells express Oct-4 and Nanog, 2 molecular markers that are indicative of pluripotency.³ Two cell types have been identified in amniotic tissues that possess stem cell-like characteristics: human amniotic epithelial cells and human amniotic mesenchymal stromal cells.⁴ Both of these cell types have demonstrated the ability to differentiate into various cell lineages, including endothelial cells, adipocytes, myogenic cells, neurogenic cells, chondrocytes, tenocytes, and osteogenic cells.^5-7 These previously reported findings indicate that amniotic cells and tissue have the capability to generate mesenchymal tissues.

FDA Classification and Available Forms

The US Food and Drug Administration (FDA) classifies amnion as an allograft tissue under Human Cells, Tissues, and Cellular and Tissue-Based Products (HCT/Ps) 361. To meet criteria, the tissue needs to be minimally manipulated. It is to be for homologous use and cannot be combined with other cells or tissues. There can be no systemic effect or dependence on the metabolic activity of living cells to achieve its primary function. The tissue has to have a localized effect in vivo. Therefore, amnion allograft tissue can be commercialized, provided it is not marketed as a stem cell product or to contain viable cells.

Amniotic tissue is commercially available in several forms.

Safety

Amniotic tissue has been used for over 100 years in burn, ophthalmology, and chronic wound patients with favorable outcomes and no adverse effects reported in the literature. Unlike embryonic stem cells, which may be tumorigenic,⁸ amniotic cells do not possess any known tumorigenicity.⁹ In one study, 50 immunodeficient mice were injected with 1 to 2 million amniotic epithelial cells and observed for a maximum of 516 days with no tumorigenicity observed in any of the animals.¹⁰ In another study, amniotic epithelial cells were implanted into the forearms of healthy volunteers and no immunologic response was observed in any of the recipients.¹¹ Furthermore, viable amniotic cells were recovered via biopsy 7 weeks following transplantation, demonstrating viability of the transplanted cells.¹¹ The lack of tumorigenicity and immunologic response in hosts is due in part to the fact that amniotic cells do not express human leukocyte antigen class II antigens and only express class I antigens in small amounts.³

Advantages of Amnion Tissue

Amniotic tissue is readily available, as it is often discarded after childbirth. The use of this tissue poses no added risk to the fetus or mother, eliminating the ethical concerns associated with obtaining embryonic stem cells. Amniotic tissue is comprised of an extracellular matrix, which acts as a natural scaffold for cellular attachment and structural support for cells as well as collagen types I, III, IV, V, and VI, hyaluronic acid, and a host of growth factors.¹² In addition, it possesses antimicrobial properties, including beta-defensins.¹³

Amniotic tissue has been shown to exert an anti-inflammatory effect by inhibiting the inflammatory cascade. Specifically, it has been shown to inhibit cytokines such as tumor necrosis factor-alpha in the presence of dendritic cells,¹⁴ as well as inhibiting transforming growth factor-beta, interleukin-8, and fibroblast proliferation.¹⁵ These findings indicate that amniotic tissue has the ability to dampen the “cytokine storm” that occurs after an injury in an adult, which would lead to beneficial impacts on healing and scar formation in patients.¹⁶

Basic Science and Animal Studies

Several studies have demonstrated promising outcomes for orthopedic applications in vitro. A comparison of osteogenic potential found that amniotic fluid-derived cells were able to produce approximately 5 times more mineralized matrix than bone marrow-derived mesenchymal stem cells.¹⁷ More recently, Si and colleagues¹⁸ compared the osteogenic potential of human amniotic epithelial cells, amniotic cells, and human bone marrow-derived mesenchymal stem cells. They found that all 3 cell lines were osteogenic, though the amniotic epithelial cells had better immunomodulatory properties and marginally less osteogenic potential than the other 2 cell types. Furthermore, several in vivo animal studies have demonstrated the ability of human amniotic cells to stimulate bone growth in rats,^19,20 rabbits,²¹ and sheep.²²

Amniotic tissue also possesses potential for chondrogenesis. Cryopreserved human amniotic membrane cells used for in vitro human osteoarthritis tissue scaffolds did not differentiate in culture, and they integrated and repaired damaged articular cartilage.²³ Various in vitro^24,25 and animal in vivo^26,27 studies have reported similar supportive findings. Kunisaki and colleagues²⁸ used sheep amniotic fluid mesenchymal stem cells to reconstruct lamb tracheal cartilage in utero, concluding that cells obtained from the amniotic fluid possess chondrogenic capabilities. Further in utero lamb studies of cartilage artificial defects, given 7 days to settle before adding a hypocellular matrix as a scaffold, showed chondrocyte density and cell architecture was restored at the defect site after 28 days without the formation of an inflammatory response or scar tissue.²⁹

Amniotic tissue has had similar success in tendon repair studies in vivo.^9,30,31 Barboni and colleagues³² implanted amniotic epithelial cells (AECs) into artificially created sheep Achilles tendon defects in situ, inducing superior structural and mechanical recovery in the defects at a faster rate compared to controls not receiving AECs. Healing via AECs started at the healthy tissue around the borders of the defect and progressed centrally, suggesting recruitment of native progenitor cells to the lesion.³² Kueckelhaus and colleagues³³ investigated the role of amnion-derived cellular cytokine solution in the healing of transections of rat Achilles tendons, reporting improved mechanical properties of healing tendons at early time points compared to controls. Beredjiklian and colleagues³⁴ compared the healing of transected extensor tendons of pregnant ewes and of their fetus in utero, reporting a reparative form of healing with scar formation in adult subjects and regenerative form of healing without scar formation or inflammation in fetal subjects.

Amniotic tissue has properties that prevent adhesion formation around tendons following injury and reconstruction.³⁵ Ozgenel³⁶ investigated the effects of hyaluronic acid and amniotic membrane alone and in combination on the presence of adhesions and the rate of healing following chicken flexor tendon repair. The study found amniotic membrane wrapped around the repaired tendon was superior in preventing adhesion formation. Kim and colleagues³⁷ report a similar reduction in fibrosis and adhesion following application of a human amniotic membrane wrap to rabbit ulnar neurorrhaphy sites.

This barrier function of amniotic tissue has also been investigated in the prevention of surgical scarring and peridural fibrosis in animal models following spinal discectomy. A study in canine models showed a reduction of scarring following the application of cross-linked amniotic membrane compared to freeze dried amniotic membrane.³⁸ Similar reductions in scarring in rat models with the application of freeze-dried amniotic membrane compared to negative controls have been reported.³⁹

Human Studies

A randomized trial investigated the outcomes of prenatal vs postnatal repair of myelomeningocele in humans, finding a reduced need for implanted shunts and improved functional outcomes at 30 months of life in the prenatal intervention group compared to the postnatal group.⁴⁰ This study was concluded early due to the efficacy of prenatal surgery and the benefit of nervous system repair in utero in the presence of amniotic growth factors.

Vines and colleagues⁴¹ performed a 6-patient feasibility study using amnion injections to treat symptomatic knee osteoarthritis. Each patient received a single intra-articular cryopreserved amniotic suspension allograft (ASA) injection and was followed for 1 year. No adverse outcomes were reported, with the only abnormal finding being a small increase in serum immunoglobulin G and immunoglobulin E levels. Intra-articular ASA injection was found to be safe, but a large-scale trial investigating symptomatic relief was recommended.⁴¹

Most of the human studies using amnion pertain to foot and ankle surgery. Its use as a treatment for diabetic foot ulcers and recalcitrant plantar fasciitis was one of the early-recognized successes.^42-45 Zelen and colleagues⁴⁶ investigated the applications of injectable micronized dehydrated human amniotic/chorionic membrane as an alternative to surgical intervention in the treatment of refractory plantar fasciitis. This prospective, randomized trial with 45 patients showed significant improvement in plantar fasciitis symptoms at 8 weeks compared to controls (saline injections). A similar study compared the use of cryopreserved human amniotic membrane (c-hAM) injections to corticosteroid injections in plantar fasciitis patients.⁴⁷ The results indicated that c-hAM is safe and comparable to corticosteroids, with the authors noting that pain improvement was greatest in patients receiving 2 injections of c-hAM at 18 weeks.

Tendon wrapping, in which the amniotic membrane is laid over a tendon repair, has been reported with success. Amniotic membrane is superior to collagen for tendon wrapping as it actively contributes to healing while minimizing adhesions, which collagen alone cannot do.⁴⁸ The membrane serves as a protective sheath around repaired tendons with anti-inflammatory, anti-adhesive, immunomodulatory, and antimicrobial benefits. A 124-patient study demonstrated the safety of using amnion in this manner, and the authors reported a decreased rate of complication compared to previously published data.⁴⁹ Another study of 14 patients undergoing foot and ankle surgery with tendon wrapping reported clinical improvement with reduced pain and greater functional outcomes postoperatively compared to preoperative measurements.⁵⁰

Conclusion

Amniotic membrane-derived tissues are safe and non-tumorigenic, producing an abundance of growth factors that have shown promise as tissue scaffolds and as aids in the regeneration of human bone and soft tissues. Amnion applications in orthopedic surgery may be numerous, but development is ongoing. Given the vast array of in vitro and in vivo animal data supporting the benefits of amnion in tissue regeneration, orthopedic surgeons and researchers should place emphasis on conducting clinical studies to validate the safety and efficacy of amniotic cells in the treatment of orthopedic conditions.

Am J Orthop. 2016;45(7):E421-E425. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.