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Background: The Articular Surface Replacement™ (ASR™) metal-on-metal hip arthroplasty system (DePuy Orthopaedics, Inc, Warsaw, IN, USA) reportedly has a higher than anticipated early failure rate leading to a voluntary recall. This prompted us to evaluate all ASR™ components implanted at our center.Questions/purposes: In all ASR™ components, we reported (1) revision rate, (2) blood metal ion levels, and (3) intraoperative findings for revisions related to adverse reaction to metal debris (ARMD).Methods: We retrospectively reviewed all 172 patients (190 hips) who underwent THA (149 hips) or hip resurfacing (41 hips) with the ASR™ system. We determined failure rates. We obtained blood metal ion concentrations from 93 patients at last followup. We evaluated MRI studies and intraoperative histopathology. Minimum followup was 12 months (mean, 40 months; range, 12-74 months).Results: At latest followup, we had revised 24 of 190 hips (13%): in 18 patients with THA and five patients with resurfacing. Mean time to revision was 45 months (range, 12-75 months). Mean blood concentrations were 13 μg/L (range, 0-150 μg/L) for cobalt and 6 μg/L (range, 0-87 μg/L) for chromium. Mean prerevision blood metal ion levels were higher in the revised group (cobalt: 48 μg/L; chromium: 18 μg/L) than in the nonrevised group (cobalt: 5 μg/L; chromium: 2 μg/L). ARMD was present in 14 of the 24 hips revised in this study.Conclusions: Surgeons must have a low threshold for concern for ARMD in patients with ASR™ systems. Blood metal ion levels and MRI can be used to evaluate patients with underperforming implants. Intraoperative histopathologic analysis and joint fluid cytology can help diagnose ARMD at the time of revision.Level Of Evidence: Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: The best method for managing large bone defects during revision knee arthroplasty is unknown. Metaphyseal fixation using porous tantalum cones has been proposed for severe bone loss. Whether this approach achieves osseointegration with low complication rates is unclear.Questions/purposes: We therefore asked: (1) What is the risk of infection in revision knee arthroplasty with large bone defects reconstructed with porous tantalum cones? (2) What is the rate of osseointegration with these cones? (3) What is the rate of loosening and reoperation? (4) Is knee function restored?Methods: We retrospectively reviewed 27 patients who had 33 tantalum cones (nine femoral, 24 tibial) implanted during 27 revision knee arthroplasties. There were 14 women and 13 men with a mean age of 64.6 years. Preoperative diagnosis was reimplantation for infection in 13 knees, aseptic loosening in 10, and wear-osteolysis in four. Patients were evaluated clinically and radiographically using the score systems of the Knee Society and followed for a minimum of 2 years (mean, 3.3 years; range, 2-5.7 years).Results: One knee with two cones was removed for infection. All but one cone showed osseointegration. One knee was revised for femoral cone and component loosening. There was one reoperation for femoral shaft fracture and one for superficial dehiscence. The mean Knee Society pain score improved from 40 points preoperatively to 79 points postoperatively. The mean function score improved from 19 points to 47 points.Conclusions: Our observations suggest metaphyseal fixation with tantalum cones can be achieved. Longer-term followup is required to determine whether the fixation is durable. [ABSTRACT FROM AUTHOR]

Recently, improved metal-on-metal bearing technology has led to the reemergence of resurfacing as a reasonable option for total hip arthroplasty. During the course of a prospective multicenter FDA-IDE evaluation of metal-on-metal total hip resurfacings, we modified our indications and emphasized surgical technique where the femoral surface area was small due to femoral cysts and small component size. We assessed the influence of these changes on complication rates in the first cohort of 292 patients and the second of 724, and then compared these outcomes in the second cohort with historical reports of resurfacing. We had a minimum followup of 24 months (mean, 33 months; range, 24-60 months). After changes were made in the indications and technique, the overall complication rate decreased from 13.4% to 2.1% with the femoral neck fracture rate reduced from 7.2% to 0.8%. The outcomes of the second cohort compare with modern-day resurfacing devices and appear superior to historical results. The data suggest patients should be carefully selected and technique optimized to reduce complications. Long-term followup is required to see if these promising results will be maintained. [ABSTRACT FROM AUTHOR]

Background: Osteonecrosis of the femoral head is a debilitating condition characterized by progressive degeneration of bone that eventually leads to collapse of the femoral head in the majority of patients. Femoral head-sparing procedures have been more successful in pre-collapse stages of osteonecrosis than in post-collapse stages, although some patients with early post-collapse disease have had no additional progression of the disorder. Nevertheless, the effects of collapse on the articular cartilage are not well understood, and radiographic staging of femoral head collapse does not address the condition of the articular cartilage.Methods: In the current study, we investigated the relationship between the mechanical properties of post-collapse articular cartilage and the histologic findings and macroscopic grades of the articular cartilage from hips with stage-IV osteonecrosis, those with stage-V osteonecrosis, and those without osteonecrosis.Results: The cartilage from both stage-IV and stage-V hips showed significant degeneration compared with the normal control cartilage, but there was no significant difference between the two stages. There was significant variability in the histologic and mechanical properties of these samples that correlated strongly with the gross appearance of the cartilage surface but not with the lesion size.Conclusions: These results suggest that articular cartilage that appears macroscopically normal may remain mechanically functional even in patients with large osteonecrotic lesions or a late radiographic stage of the disease. [ABSTRACT FROM AUTHOR]

Background: Bone ingrowth into a cementless prosthesis can be achieved by both porous and hydroxyapatite coatings. The purpose of this study was to compare the performance of a hydroxyapatite-coated proximal sleeve and a porous bead-coated sleeve in patients managed with a modular revision hip system.Methods: Between August 1992 and December 1996, fifty-three consecutive femoral revisions performed with an S-ROM stem in fifty-two patients were prospectively randomized at the time of surgery to either a hydroxyapatite-coated or a porous-coated sleeve. All patients were evaluated clinically and radiographically at three months, six months, and yearly for a minimum of two years (average, four years; range, two to 7.5 years). Femoral defects were classified according to the criteria of Paprosky et al. Six patients died and four patients were lost to follow-up, leaving forty-two patients (forty-three hips) as the final study group.Results: For the entire group, two femoral stems, one of which had been implanted in a hip with a Paprosky type-II femoral defect and the other in a hip with a Paprosky type-IIIB femoral defect, required a repeat revision, one for pain and the other for aseptic loosening. Radiographic evidence of bone ingrowth was observed in 96% (twenty-six) of the twenty-seven femora with type-I or II defects and in 81% (thirteen) of the sixteen femora with type-III defects. Femoral component survival, with use of revision as the end point, was 95% at four years for the entire group. The Harris hip scores were not significantly different when stratified by implant type, but were significantly different when stratified by bone loss (p < 0.05). In the femora with type-I or II defects, no difference was detected between those treated with a hydroxyapatite-coated implant and those that received a porous-coated implant with respect to bone ingrowth. However, in femora with type-III defects, the likelihood of the development of bone ingrowth was 2.6 (95% confidence interval, 1.3 to 5.17) times greater in hips that received a hydroxyapatite-coated implant (all eight developed ingrowth) than in hips that had a porous-coated implant (five of eight developed ingrowth) (p = 0.05).Conclusions: Bone fixation was achieved more often with hydroxyapatite-coated sleeves in femora with Paprosky type-III defects, but no significant difference was noted in outcomes between the two implant types when used in bone with type-I or type-II femoral defects. Overall, the S-ROM modular hip stem performed better in femora with type-I or II bone defects than in femora with type-III defects.Level Of Evidence: Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: The relationship between volume and outcome of total knee arthroplasties has never been evaluated in a nationally representative sample, to our knowledge. We hypothesized that surgeons and hospitals with higher patient volumes would have better outcomes, as defined by lower mortality rates, shorter hospital stays, and lower postoperative complication rates.Methods: The 1997 Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample, Release 6, provided discharge abstracts of patients undergoing total knee arthroplasty from a national stratified probability sample. Logistic and multiple regression models were used to estimate the adjusted association of surgeon or hospital volume with rates of in-hospital mortality, pulmonary thromboembolism, deep venous thrombosis in the lower extremity, and postoperative wound infection as well as length of hospital stay. Estimates were calculated for a target population of 277,550 patients. Models were adjusted for comorbidity, age, gender, race, household income, and procedure (primary or revision arthroplasty).Results: The patients were mostly white (70.2%) and female (62.7%), with a mean age of 68.9 years. The overall in-hospital mortality rate for the target population was 0.2%, and the average length of stay was 4.6 days for the primary total knee arthroplasties and 4.9 days for the revision procedures. Surgeon volumes of at least fifteen procedures per year and hospital volumes of at least eighty-five per year were significantly and linearly associated with lower mortality rates (odds ratio = 0.56 [0.24 to 1.31] for surgeon volume of > or = 60). No other association demonstrated a significant and directionally consistent linear trend for improved outcomes.Conclusion: Patients treated by providers with lower caseload volumes had higher rates of mortality following total knee arthroplasty in 1997. Proposing volume standards could decrease patient mortality following this procedure. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to define the use of the extraarticular, lateral reconstruction in the spectrum of patients with cruciate deficiency. A review was conducted of 112 consecutive patients with a MacIntosh-type iliotibial and band transfer done between 1972 and 1986. Fifty-six of the patients had a partial or complete meniscectomy, and 24% had failed a previous extraarticular procedure. Eighty-one percent of the patients had radiographic degenerative changes at the knee at the outset. Ninety-eight percent had an anterior drawer of 1 + or greater; 97% had a pivot shift greater than trace. All patients had symptomatic knee instability. Seventy-seven of the 112 patients (69%) were available for followup (range, 24 months to 15.5 years; median, 7.6). Twenty-three patients (21%) returned for examination, KT-1000 and Cybex testing, and radiographs. An additional 54 patients (48%) were seen by their local physicians or returned a detailed questionnaire that included the Cincinnati knee rating scale. At final followup, 38% complained of some knee instability, 36% had recurrent effusions, 61% had intermittent pain, 79% had radiographic gonarthrosis, and 25% had undergone additional surgery. Forty-two percent had a positive Lachman after surgery, and only 15% had a pivot shift. The mean knee score was 81.1. Previous extraarticular anterior cruciate ligament reconstruction, mensicectomy, and generalized ligamentous laxity were associated with a significant decrement in the knee rating (P = 0.05). Ligamentous laxity strongly correlated with symptoms of giving way. Also, the incidence of pain, swelling, giving way, and activity modification correlated with meniscectomy and increased as the length of followup increased for all patients. In conclusion, this study suggests that extraarticular lateral reconstruction does not restore normal knee function, but does eliminate the pivot shift and may decrease the incidence of repeat knee injury in selected patients with symptomatic cruciate deficiency. Lateral reconstruction alone should be limited to low-demand patients without previous meniscectomy, or generalized ligamentous laxity in whom more anatomic reconstruction is not possible. [ABSTRACT FROM AUTHOR]

Background: Recovery following total joint arthroplasty is patient-specific, yet groups of patients tend to fall into certain similar patterns of recovery. The purpose of this study was to identify and characterize recovery patterns following total hip arthroplasty (THA) and total knee arthroplasty (TKA) using patient-reported outcomes that represent distinct health domains. We hypothesized that recovery patterns could be defined and predicted using preoperative data., Methods: Adult patients were recruited from a large, urban academic center. To model postoperative responses to THA and TKA across domains such as physical health, mental health, and joint-specific measures, we employed a longitudinal clustering algorithm that incorporates each of these health domains. The clustering algorithm from multiple health domains allows the ability to define distinct recovery trajectories, which could then be predicted from preoperative and perioperative factors using a multinomial regression., Results: Four hundred forty-one of 1134 patients undergoing THA and 346 of 921 undergoing TKA met eligibility criteria and were used to define distinct patterns of recovery. The clustering algorithm was optimized for 3 distinct patterns of recovery that were observed in THA and TKA patients. Patients recovering from THA were divided into 3 groups: standard responders (50.8%), late mental responders (13.2%), and substandard responders (36.1%). Multivariable, multinomial regression suggested that these 3 groups had defined characteristics. Late mental responders tended to be obese ( P  = .05) and use more opioids ( P  = .01). Substandard responders had a larger number of comorbidities ( P  = .02) and used more opioids ( P  = .001). Patients recovering from TKA were divided among standard responders (55.8%), poor mental responders (24%), and poor physical responders (20.2%). Poor mental responders were more likely to be female ( P  = .04) and American Society of Anesthesiologists class III/IV ( P  = .004). Poor physical responders were more likely to be female ( P  = .03), younger ( P  = .04), American Society of Anesthesiologists III/IV ( P  = .04), use more opioids ( P  = .02), and be discharged to a nursing facility ( P  = .001). The THA and TKA models demonstrated areas under the curve of 0.67 and 0.72., Conclusions: This multidomain, longitudinal clustering analysis defines 3 distinct patterns in the recovery of THA and TKA patients, with most patients in both cohorts experiencing robust improvement, while others had equally well defined yet less optimal recovery trajectories that were either delayed in recovery or failed to achieve a desired outcome. Patients in the delayed recovery and poor outcome groups were slightly different between THA and TKA. These groups of patients with similar recovery patterns were defined by patient characteristics that include potentially modifiable comorbid factors. This research suggests that there are multiple defined recovery trajectories after THA and TKA, which provides a new perspective on THA and TKA recovery., Level of Evidence: III., (© 2024 The Authors.)

Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest form is provided with the online version of the article (http://links.lww.com/JBJS/H151).

Background: Gluteal tendon tears (GTT) can cause pain and weakness of the hip. We analyze the impact of gluteal muscle fatty degeneration, atrophy and tear morphology on clinical outcomes of surgical repair., Methods: All sequential patients receiving surgical repair of GTTs via anchor sutures between 1/2015 and 11/2018 were retrospectively identified. MRIs were reviewed by a radiologist for tendon retraction, muscle atrophy and tear size. The Goutallier-Fuchs Classification (GFC) was used to quantify fatty degeneration as < 2° or ≥ 2°. Demographic and clinical variables were abstracted from the electronic records. The surveys HHS Section 1 and HOOS Jr. were obtained at last follow-up. The Pearson correlation and one-way ANOVA tests served for statistical analysis of clinical variance., Results: 38 patients were identified, 29 (76.3%) were female. The average age was 67. Of the 11 (28.9%) patients with a prior hip arthroplasty 87.5% of primary THAs had a direct lateral approach. 29 (76.3%) patients were treated open and 9 (23.7%) arthroscopically. At an average follow-up of 20.9 months, patients reported a significant improvement in pain (97%), analgesic use (85.7%), limp (52.6%) and abduction strength (54.2%) (all: P ≤ 0.01). GFC ≥ 2° were associated with significantly worse outcomes in terms of limp (0.19/3 vs. 1.2/3, P = 0.05), HHS-S1 (58.19 vs. 71.68, P = 0.04) and complication rates (37.5% vs. 0%, P = 0.02). There was a strong correlation between tear retraction (P = 0.005), tear size (P = 0.009) and muscle atrophy (P = 0.001) with GFC ≥ 2° but not with clinical outcomes. GFC ≥ 2° was strongly related to lateral THA exposures (P < 0.001). Surgical approach had no impact on clinical outcomes., Conclusion: While fatty degeneration can negatively impact functional outcomes, pain relief is reliably achieved. Tear morphology and muscle atrophy did not correlate with outcomes in this patient cohort. Patients should be counseled to expect a residual limp after surgery if they have GFC ≥ 2° on MRI., (© 2021. The Author(s).)

Musculoskeletal conditions impede patient biomechanical function. However, clinicians rely on subjective functional assessments with poor test characteristics for biomechanical outcomes because more advanced assessments are impractical in the ambulatory care setting. Using markerless motion capture (MMC) in clinic to record time-series joint position data, we implemented a spatiotemporal assessment of patient kinematics during lower extremity functional testing to evaluate whether kinematic models could identify disease states beyond conventional clinical scoring. 213 trials of the star excursion balance test (SEBT) were recorded by 36 subjects during routine ambulatory clinic visits using both MMC technology and conventional clinician scoring. Conventional clinical scoring failed to distinguish patients with symptomatic lower extremity osteoarthritis (OA) from healthy controls in each component of the assessment. However, principal component analysis of shape models generated from MMC recordings revealed significant differences in subject posture between the OA and control cohorts for six of the eight components. Additionally, time-series models of subject posture change over time revealed distinct movement patterns and reduced overall postural change in the OA cohort compared to the controls. Finally, a novel metric quantifying postural control was derived from subject specific kinematic models and was shown to distinguish OA (1.69), asymptomatic postoperative (1.27), and control (1.23) cohorts (p = 0.0025) and to correlate with patient-reported OA symptom severity (R = -0.72, p = 0.018). Time series motion data have superior discriminative validity and clinical utility than conventional functional assessments in the case of the SEBT. Novel spatiotemporal assessment approaches can enable routine in-clinic collection of objective patient-specific biomechanical data for clinical decision-making and monitoring recovery., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Halvorson et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/G889).

Purpose: To assess the correlation between changes in hip capsule morphology with improvements in patient-reported outcome (PRO) scores after arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) using the periportal capsulotomy technique., Methods: Twenty-eight patients with cam morphology FAIS (without arthritis, dysplasia, or hypermobility) were prospectively enrolled before arthroscopic labral repair and femoroplasty through periportal capsulotomy (anterolateral/midanterior portals) without closure. Patients completed the Hip Disability and Osteoarthritis Outcomes Score (HOOS) and had nonarthrographic 3T magnetic resonance imaging (MRI) scans of the affected hip before and 1 year after surgery. Anterior capsule thickness, posterior capsule thickness, anterior-posterior capsule thickness ratio, and proximal-distal anterior capsule thickness ratio were measured on axial-oblique MRI sequences. Pearson correlation coefficients were calculated to determine the association between hip capsule morphology and PRO scores., Results: Postoperative imaging showed that for all 28 patients (12 female), labral repairs and capsulotomies had healed within 1 year of surgery. Analysis revealed postoperative decreases in anterior hip capsule thickness (1395.4 ± 508.4 mm 3 vs 1758.4 ± 487.9 mm 3 ; P = .003) and anterior-posterior capsule thickness ratio (0.92 ± 0.33 vs 1.12 ± 0.38; P = .02). Higher preoperative anterior-posterior capsule thickness ratio correlated with lower preoperative scores for HOOS pain (R = -0.43; P = .02), activities of daily living (ADL) (R = -0.43; P = .02), and sport (R = -0.38; P = .04). Greater decrease from preoperative to postoperative anterior-posterior capsule thickness ratio correlated with greater improvement for HOOS pain (R = -0.40; P = .04), ADL (R = -0.45; P = .02), and sport (R = -0.46; P = .02)., Conclusions: Periportal capsulotomy without closure demonstrates capsule healing by 1 year after arthroscopic FAIS treatment. Changes in hip capsule morphology including decreased anterior-posterior capsule thickness ratio after surgery may be correlated with improvements in patient pain, function, and ability to return to sports., Level of Evidence: Level II, prospective cohort study., (Copyright © 2021 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest form is provided with the online version of the article (http://links.lww.com/JBJS/G738).

Background: The incidence of transfusion in contemporary revision total hip arthroplasty (THA) remains high despite recent advances in blood management, including the use of tranexamic acid. The purpose of this prospective investigation was to determine independent risk factors for transfusion in revision THA., Methods: Six centers prospectively collected data on 175 revision THAs. A multivariable logistic analysis was performed to determine independent risk factors for transfusion. Revisions were categorized into subgroups for analysis, including femur-only, acetabulum-only, both-component, explantation with spacer, and second-stage reimplantation. Patients undergoing an isolated modular exchange were excluded., Results: Twenty-nine patients required at least one unit of blood (16.6%). In the logistic model, significant risk factors for transfusion were lower preoperative hemoglobin, higher preoperative international normalized ratio (INR), and longer operative time (P < .01, P = .04, P = .05, respectively). For each preoperative 1g/dL decrease in hemoglobin, the chance of transfusion increased by 79%. For each 0.1-unit increase in the preoperative INR, transfusion chance increased by 158%. For each additional operative hour, the chance of transfusion increased by 74%. There were no differences in transfusion rates among categories of revision hip surgery (P = .23). No differences in demographic or surgical variables were found between revision types., Conclusion: Despite the use of tranexamic acid, transfusions are commonly required in revision THA. Preoperative hemoglobin and INR optimization are recommended when medically feasible. Efforts should also be made to decrease operative time when technically possible., (Copyright © 2021 Elsevier Inc. All rights reserved.)

As the life expectancy of the worldwide population increases, the number of hip fractures in the elderly cohort is expected to grow. It is important for surgeons to critically analyze available treatment options for these injuries, with the goal of optimizing outcomes and minimizing complications. Femoral neck fractures make up approximately half of all hip fractures. Nonoperative treatment of valgus-impacted and nondisplaced (Garden I and II) femoral neck fractures has high rates of secondary displacement, osteonecrosis, and nonunion; only patients with notable risk for perioperative complications are treated nonoperatively. Surgical intervention is the standard of care, with options including internal fixation (IF) with multiple cancellous screws or a sliding hip screw, hemiarthroplasty, or total hip arthroplasty. Patients with a posterior tilt of greater than 20° have a high rate of revision surgery when treated with IF and may benefit from primary arthroplasty. Furthermore, primary arthroplasty has demonstrated lower revision surgery rates and equivalent postoperative mortality when compared with IF. Surgeons should be aware of the functional outcomes, complications, revision surgery rates, and mortality rates associated with each treatment modality to make a patient-specific decision regarding their care., (Copyright © 2021 by the American Academy of Orthopaedic Surgeons.)

The relationship between morphological characteristics of the hip capsule and patient symptoms in the setting of femoroacetabular impingement (FAI) is undefined. In this study, patients with symptomatic FAI prospectively underwent 3T magnetic resonance (MR) imaging of the affected hip and completed the hip disability and osteoarthritis outcome score (HOOS) to determine the correlation between hip capsule anatomy and patient symptoms. Anterior hip capsule volume, posterior capsule volume, anterior-posterior capsule volume ratio, and proximal-distal volume ratio in the anterior capsule were quantified and measured using axial-oblique intermediate-weighted 3D fast spin echo MR images. A total of 35 patients (35 hips) were included for analysis (mean age: 30.6 years; mean body mass index [BMI]: 24.9 kg/m 2 ; 57% male). The mean alpha angle was 62.2° ± 4.7°, the mean anterior hip capsule volume was 1705.1 ± 450.3 mm 3 , the mean posterior hip capsule volume was 1284.8 ± 268.5 mm 3 , the mean anterior to posterior capsule volume ratio was 1.1 ± 0.39, and the mean proximal to distal volume ratio of the anterior capsule was 0.65 ± 0.28. There was no correlation between age, gender, or BMI, and any hip capsule characteristics. Worse scores on the HOOS pain scale were correlated with increased anterior to posterior volume ratio (r = -.38; 95% confidence interval: -0.06 to -0.63). In conclusion, hip capsule morphology correlates with patient symptoms in the setting of FAI as increased anterior capsular volume, relative to posterior capsular volume, is associated with greater patient pain., (© 2020 Orthopaedic Research Society. Published by Wiley Periodicals LLC.)

Background: The purpose of this multicenter, randomized trial was to determine the optimal dosing regimen of tranexamic acid (TXA) to minimize perioperative blood loss in revision total hip arthroplasty., Methods: Six centers prospectively randomized 175 patients to 1 of 4 regimens: (1) 1-g intravenous (IV) TXA prior to incision (the single-dose IV group), (2) 1-g IV TXA prior to incision followed by 1-g IV TXA after arthrotomy wound closure (the double-dose IV group), (3) a combination of 1-g IV TXA prior to incision and 1-g intraoperative topical TXA (the combined IV and topical group), or (4) 3 doses totaling 1,950-mg oral TXA (the multidose oral group). Randomization was based on revision subgroups to ensure equivalent group distribution. An a priori power analysis (α = 0.05; β = 0.80) determined that 40 patients per group were required to identify a >1-g/dL difference in postoperative hemoglobin reduction between groups. Per-protocol analysis involved an analysis of variance, Fisher exact tests, and two 1-sided t tests for equivalence. Demographic and surgical variables were equivalent between groups., Results: No significant differences were found between TXA regimens when evaluating reduction in hemoglobin (3.4 g/dL for the single-dose IV group, 3.6 g/dL for the double-dose IV group, 3.5 g/dL for the combined IV and topical group, and 3.4 g/dL for the multidose oral group; p = 0.95), calculated blood loss (p = 0.90), or transfusion rates (14% for the single-dose IV group, 18% for the double-dose IV group, 17% for the combined group, and 17% for the multidose oral group; p = 0.96). Equivalence testing revealed that all possible pairings were statistically equivalent, assuming a >1-g/dL difference in hemoglobin reduction as clinically relevant. There was 1 venous thromboembolism, with no differences found between groups (p = 1.00)., Conclusions: All 4 TXA groups tested had equivalent blood-sparing properties in the setting of revision total hip arthroplasty, with a single venous thromboembolism reported in this high-risk population. Based on the equivalence between groups, surgeons should utilize whichever of the 4 investigated regimens is best suited for their practice and hospital setting. Given the transfusion rate in revision total hip arthroplasty despite TXA utilization, further work is required in this area., Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Objective: During the COVID-19 pandemic, quaternary-care facilities continue to provide care for patients in need of urgent and emergent invasive procedures. Perioperative protocols are needed to streamline care for these patients notwithstanding capacity and resource constraints., Methods: A multidisciplinary panel was assembled at the University of California, San Francisco, with 26 leaders across 10 academic departments, including 7 department chairpersons, the chief medical officer, the chief operating officer, infection control officers, nursing leaders, and resident house staff champions. An epidemiologist, an ethicist, and a statistician were also consulted. A modified two-round, blinded Delphi method based on 18 agree/disagree statements was used to build consensus. Significant disagreement for each statement was tested using a one-sided exact binomial test against an expected outcome of 95% consensus using a significance threshold of p < 0.05. Final triage protocols were developed with unblinded group-level discussion., Results: Overall, 15 of 18 statements achieved consensus in the first round of the Delphi method; the 3 statements with significant disagreement (p < 0.01) were modified and iteratively resubmitted to the expert panel to achieve consensus. Consensus-based protocols were developed using unblinded multidisciplinary panel discussions. The final algorithms 1) quantified outbreak level, 2) triaged patients based on acuity, 3) provided a checklist for urgent/emergent invasive procedures, and 4) created a novel scoring system for the allocation of personal protective equipment. In particular, the authors modified the American College of Surgeons three-tiered triage system to incorporate more urgent cases, as are often encountered in neurosurgery and spine surgery., Conclusions: Urgent and emergent invasive procedures need to be performed during the COVID-19 pandemic. The consensus-based protocols in this study may assist healthcare providers to optimize perioperative care during the pandemic.

Aims: The aim of this study was to evaluate the ability of a machine-learning algorithm to diagnose prosthetic loosening from preoperative radiographs and to investigate the inputs that might improve its performance., Methods: A group of 697 patients underwent a first-time revision of a total hip (THA) or total knee arthroplasty (TKA) at our institution between 2012 and 2018. Preoperative anteroposterior (AP) and lateral radiographs, and historical and comorbidity information were collected from their electronic records. Each patient was defined as having loose or fixed components based on the operation notes. We trained a series of convolutional neural network (CNN) models to predict a diagnosis of loosening at the time of surgery from the preoperative radiographs. We then added historical data about the patients to the best performing model to create a final model and tested it on an independent dataset., Results: The convolutional neural network we built performed well when detecting loosening from radiographs alone. The first model built de novo with only the radiological image as input had an accuracy of 70%. The final model, which was built by fine-tuning a publicly available model named DenseNet, combining the AP and lateral radiographs, and incorporating information from the patient's history, had an accuracy, sensitivity, and specificity of 88.3%, 70.2%, and 95.6% on the independent test dataset. It performed better for cases of revision THA with an accuracy of 90.1%, than for cases of revision TKA with an accuracy of 85.8%., Conclusion: This study showed that machine learning can detect prosthetic loosening from radiographs. Its accuracy is enhanced when using highly trained public algorithms, and when adding clinical data to the algorithm. While this algorithm may not be sufficient in its present state of development as a standalone metric of loosening, it is currently a useful augment for clinical decision making. Cite this article: Bone Joint J 2020;102-B(6 Supple A):101-106.

Background: Little is known about the relative efficacy of open (OGR) vs endoscopic (EGR) gluteal tendon repair of gluteal tendon tears in minimizing pain and restoring function. Our aim is to compare these 2 surgical techniques and quantify their impact on clinical outcomes., Methods: All patients undergoing gluteal tendon tear repair at our institution between 2015 and 2018 were retrospectively reviewed. Pain scores, limp, hip abduction strength, and the use of analgesics were recorded preoperatively and at last follow-up. The Hip disability and Osteoarthritis Outcome Score Junior and Harris Hip Score Section1 were obtained at last follow-up. Fatty degeneration was quantified using the Goutallier-Fuchs Classification (GFC). Statistical analysis was conducted using one-way analysis of variance and t-tests., Results: Forty-five patients (mean age 66, 87% females) met inclusion criteria. Average follow-up was 20.3 months. None of the 10 patients (22%) undergoing EGR had prior surgery. Of 35 patients (78%) undergoing OGR, 12 (27%) had prior hip replacement (75% via lateral approach). The OGRs had more patients with GFC ≥2 (50% vs 11%, P = .02) and used more anchors (P = .03). Both groups showed statistical improvement (P ≤ .01) for all outcomes measured. GFC >2 was independently associated with a worst limp and Harris Hip Score Section 1 score (P = .05). EGR had a statistically higher opioid use reduction (P < .05) than OGR. Other comparisons between EGR and OGR did not reach statistical significance., Conclusion: In this series, open vs endoscopic operative approach did not impact clinical outcomes. More complex tears were treated open and with more anchors. Fatty degeneration adversely impacted outcomes. Although further evaluation of the efficacy of EGR in complex tears is indicated, both approaches can be used successfully., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: As the demand for knee arthroplasty increases, risk assessment and counseling are critical for optimal patient outcomes perioperatively. The purpose of this study was to determine if specific complications occurring after unilateral knee replacement predict the risk of recurrence after a staged replacement of the contralateral knee for patients with bilateral symptomatic disease., Methods: Linked, nationwide data from the U.S. Hospital Cost and Utilization Project from 2005 to 2014 were used to measure the occurrence of complications after the first and second procedures in staged bilateral total knee arthroplasties (TKAs). Odds ratios (ORs) and conditional probabilities were determined to assess whether having a specific complication after the first TKA increased the chance that the same complication occurred after the second procedure., Results: A total of 36,278 patients who underwent staged bilateral TKAs were analyzed. All complications occurring after the first arthroplasty were associated with both a significantly increased probability and odds of recurrence following the second arthroplasty. These included myocardial infarction (OR, 56.63 [95% confidence interval (CI), 18.04 to 155.44]; p < 0.001), ischemic stroke (OR, 41.38 [95% CI, 1.98 to 275.82]; p = 0.03), other cardiac complications (OR, 7.73 [95% CI, 4.24 to 14.11]; p < 0.001), respiratory complications (OR, 8.58 [95% CI, 2.85 to 23.17]; p = 0.002), urinary complications (OR, 11.19 [95% CI, 5.44 to 22.25]; p = 0.001), hematoma (OR, 15.05 [95% CI, 7.90 to 27.27]; p < 0.001), deep vein thrombosis (OR, 7.40 [95% CI, 5.37 to 10.08]; p < 0.001), and pulmonary embolism (OR, 11.00 [95% CI, 5.01 to 23.92]; p < 0.001)., Conclusions: Medical complications that occur postoperatively after TKA are associated with a significantly increased risk of recurrence of these complications after staged replacement of the contralateral knee. Although overall complication rates remain low, patients who develop these medical complications after the first replacement should be counseled on their increased risk profile prior to the contralateral surgical procedure., Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Osteoarthritis (OA), long considered a primary disorder of articular cartilage, is commonly associated with subchondral bone sclerosis. However, the cellular mechanisms responsible for changes to subchondral bone in OA, and the extent to which these changes are drivers of or a secondary reaction to cartilage degeneration, remain unclear. In knee joints from human patients with end-stage OA, we found evidence of profound defects in osteocyte function. Suppression of osteocyte perilacunar/canalicular remodeling (PLR) was most severe in the medial compartment of OA subchondral bone, with lower protease expression, diminished canalicular networks, and disorganized and hypermineralized extracellular matrix. As a step toward evaluating the causality of PLR suppression in OA, we ablated the PLR enzyme MMP13 in osteocytes while leaving chondrocytic MMP13 intact, using Cre recombinase driven by the 9.6-kb DMP1 promoter. Not only did osteocytic MMP13 deficiency suppress PLR in cortical and subchondral bone, but it also compromised cartilage. Even in the absence of injury, osteocytic MMP13 deficiency was sufficient to reduce cartilage proteoglycan content, change chondrocyte production of collagen II, aggrecan, and MMP13, and increase the incidence of cartilage lesions, consistent with early OA. Thus, in humans and mice, defects in PLR coincide with cartilage defects. Osteocyte-derived MMP13 emerges as a critical regulator of cartilage homeostasis, likely via its effects on PLR. Together, these findings implicate osteocytes in bone-cartilage crosstalk in the joint and suggest a causal role for suppressed perilacunar/canalicular remodeling in osteoarthritis., Competing Interests: Competing interestsThe authors declare no competing interests., (© The Author(s) 2019.)

Background: The variation in articular cartilage thickness (ACT) in healthy knees is difficult to quantify and therefore poorly documented. Our aims are to (1) define how machine learning (ML) algorithms can automate the segmentation and measurement of ACT on magnetic resonance imaging (MRI) (2) use ML to provide reference data on ACT in healthy knees, and (3) identify whether demographic variables impact these results., Methods: Patients recruited into the Osteoarthritis Initiative with a radiographic Kellgren-Lawrence grade of 0 or 1 with 3D double-echo steady-state MRIs were included and their gender, age, and body mass index were collected. Using a validated ML algorithm, 2 orthogonal points on each femoral condyle were identified (distal and posterior) and ACT was measured on each MRI. Site-specific ACT was compared using paired t-tests, and multivariate regression was used to investigate the risk-adjusted effect of each demographic variable on ACT., Results: A total of 3910 MRI were included. The average femoral ACT was 2.34 mm (standard deviation, 0.71; 95% confidence interval, 0.95-3.73). In multivariate analysis, distal-medial (-0.17 mm) and distal-lateral cartilage (-0.32 mm) were found to be thinner than posterior-lateral cartilage, while posterior-medial cartilage was found to be thicker (0.21 mm). In addition, female sex was found to negatively impact cartilage thickness (OR, -0.36; all values: P < .001)., Conclusion: ML was effectively used to automate the segmentation and measurement of cartilage thickness on a large number of MRIs of healthy knees to provide normative data on the variation in ACT in this population. We further report patient variables that can influence ACT. Further validation will determine whether this technique represents a powerful new tool for tracking the impact of medical intervention on the progression of articular cartilage degeneration., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Aims: Increasingly, patients with bilateral hip arthritis wish to undergo staged total hip arthroplasty (THA). With the rise in demand for arthroplasty, perioperative risk assessment and counselling is crucial for shared decision making. However, it is unknown if complications that occur after a unilateral hip arthroplasty predict complications following surgery of the contralateral hip., Patients and Methods: We used nationwide linked discharge data from the Healthcare Cost and Utilization Project between 2005 and 2014 to analyze the incidence and recurrence of complications following the first- and second-stage operations in staged bilateral total hip arthroplasty (BTHAs). Complications included perioperative medical adverse events within 30 to 60 days, and infection and mechanical complications within one year. Conditional probabilities and odds ratios (ORs) were calculated to determine whether experiencing a complication after the first stage of surgery increased the risk of developing the same complication after the second stage., Results: A total of 13 829 patients (5790 men and 8039 women) who underwent staged BTHAs were analyzed. The mean age at first operation was 62.9 years (14 to 95). For eight of the 12 outcomes evaluated, patients who experienced the outcome following the first arthroplasty had a significantly increased probability and odds of developing that same complication following the second arthroplasty, compared with those who did not experience the complication after the first surgery. This was true for digestive complications (OR 25.67, 95% confidence interval (CI) 13.86 to 46.08; p < 0.001), urinary complications (OR 6.48, 95% CI 1.7 to 20.73; p = 0.01), haematoma (OR 12.17, 95% CI 4.55 to 31.14; p < 0.001), deep vein thrombosis (OR 4.82, 95% CI 2.34 to 9.65; p < 0.001), pulmonary embolism (OR 12.03, 95% CI 2.02 to 46.77; p = 0.01), deep hip infection (OR 534.21, 95% CI 314.96 to 909.25; p < 0.001), superficial hip infection (OR 1574.99, 95% CI 269.83 to 9291.81; p < 0.001), and mechanical malfunction (OR 117.49, 95% CI 91.55 to 150.34; p < 0.001)., Conclusion: The occurrence of certain complications after unilateral THA is associated with an increased risk of the same complication occurring after staged arthroplasty of the contralateral hip. Patients who experience these complications after unilateral hip arthroplasty should be appropriately counselled regarding their risk profile prior to undergoing staged contralateral hip arthroplasty. Cite this article: Bone Joint J 2019;101-B(6 Supple B):77-83.

Optimizing surgical instrumentation may contribute to value-based care, particularly in commonly performed procedures. We report our experience in implementing a perioperative efficiency program in 2 types of orthopedic surgery (primary total-knee arthroplasty, TKA, and total-hip arthroplasty, THA).A comparative before-and-after study with 2 participating surgeons, each performing both THA and TKA, was conducted. Our objective was to evaluate the effect of surgical tray optimization on operating and processing time, cost, and waste associated with preparation, delivery, and staging of sterile surgical instruments. The study was designed as a prospective quality improvement initiative with pre- and postimplementation operational measures and a provider satisfaction survey.A total of 96 procedures (38 preimplementation and 58 postimplementation) were assessed using time-stamped performance endpoints. The number and weight of trays and instruments processed were reduced substantially after the optimization intervention, particularly for TKA. Setup time was reduced by 23% (6 minutes, P = .01) for TKA procedures but did not differ for THA. The number of survey respondents was small, but satisfaction was high overall among personnel involved in implementation.Optimizing instrumentation trays for orthopedic procedures yielded reduction in processing time and cost. Future research should evaluate patient outcomes and incremental/additive impact on institutional quality measures.

There is a growing consensus that an accomplished curriculum vitae and prior achievement as an academician may not correlate with success as a chairperson of a contemporary academic orthopaedic department. As surgeons, formal professional education, research expertise, and clinical experience often are inadequate to foster the necessary skills and experience in executive leadership, change management, business administration, and strategy. The recruiting and hiring processes to fill academic leadership roles have been slow to adapt and recognize the skills that are necessary to be a successful chairperson. Recent research has identified emotional competency, resiliency, leadership, communication, results orientation, and personnel development as skills that correlate with success in academic leadership. Formal courses and training in executive leadership and business management may be helpful in enhancing knowledge and skills in these disciplines.

Health-care reform, market competition, cost containment, and pressure for productivity have dramatically impacted the practice of orthopaedic surgery and academic surgical training. Orthopaedic leaders and training programs are striving to identify and solve these contemporary challenges. Herein, we focus on 4 areas that currently pose important challenges to modern orthopaedic surgical departments and academic hospital systems, including the demanding and evolving skill sets that are required of physician leaders, the effects of the changing medical-legal environment on academic medicine, the impact of increased clinical productivity emphasis on surgical education, and departmental leadership transitions.

Background: The purpose of this study is to determine whether episode Target Prices in the Bundled Payment for Care Improvement (BPCI) initiative sufficiently match the complexities and expenses expected for patients undergoing hip arthroplasty for femoral neck fracture (FNF) as compared to hip degenerative joint disease (DJD)., Methods: Claims data under BPCI Model 2 were collected for patients undergoing hip arthroplasty at a single institution over a 2-year period. Payments from the index hospitalization to 90 days postoperatively were aggregated by Medicare Severity Diagnosis-Related Group (469 or 470), indication (DJD vs FNF), and categorized as index procedure, postacute services, and related hospital readmissions. Actual episode costs and Target Prices were compared in both the FNF and DJD cohorts undergoing hip arthroplasty to gauge the cost discrepancy in each group., Results: A total of 183 patients were analyzed (31 with FNFs, 152 with DJD). In total, the FNF cohort incurred a $415,950 loss under the current episode Target Prices, whereas the DJD cohort incurred a $172,448 gain. Episode Target Prices were significantly higher than actual episode prices for the DJD cohort ($32,573 vs $24,776, P < .001). However, Target Prices were significantly lower than actual episode prices for the FNF cohort ($32,672 vs $49,755, P = .021)., Conclusion: Episode Target Prices in the current BPCI model fall dramatically short of the actual expenses incurred by FNF patients undergoing hip arthroplasty. Better risk-adjusting Target Prices for this fragile population should be considered to avoid disincentives and delays in care., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Intrathecal morphine (ITM) combined with bupivacaine spinal anesthesia can improve postoperative pain, but has potential side effects of postoperative nausea/vomiting (PONV) and pruritus. With the use of multimodal analgesia and regional anesthetic techniques, postoperative pain control has improved significantly to a point where ITM may be avoided in total joint arthroplasty (TJA)., Methods: We performed a retrospective study of primary TJA patients who underwent a standardized multimodal recovery pathway and received bupivacaine neuraxial anesthesia with ITM vs bupivacaine neuraxial anesthesia alone (control)., Results: In total, 598 patients were identified (131 controls, 467 ITMs) with similar demographics. On postoperative day 0 (POD 0), ITM patients had significantly lower mean visual analog scale scores (1.5 ± 1.6 vs 2.5 ± 1.9, P < .001) and consumed less oral morphine equivalents (10.5 ± 25.4 vs 16.8 ± 27.2, P = .013). ITM patients walked further compared to controls by POD 1 (133.6 ± 159.6 vs 97.3 ± 141 m, P = .028) and were less likely to develop PONV during their entire hospital stay (38.5% vs 48.6%, P = .043). No significant differences were seen for total morphine equivalents consumption, rate of discharge to care facility, length of stay, and 90-day readmission rates., Conclusion: ITM was associated with improved POD 0 pain scores and less initial oral/intravenous opioid consumption, which likely contributes to the subsequent improved mobilization and lower rates of PONV. In the setting of a modern regional anesthesia and multimodal analgesia recovery plan for TJA, ITM can still be considered for its benefits., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Knee stiffness requiring manipulation under anesthesia (MUA) is an undesirable outcome following total knee arthroplasty (TKA), but risk factors for, and optimal timing of, MUA remain unclear., Methods: Primary TKAs performed at a single center were retrospectively reviewed. Clinical variables were compared between patients who underwent MUA and those who did not; variables that differed were utilized to identify an appropriately matched control group of non-MUA patients. The MUA group was divided into early (MUA ≤6 weeks from index) and late (>6 weeks) subgroups. Flexion values at multiple time points were compared., Results: In total, 1729 TKA patients were reviewed; MUA was performed in 62 patients. Patients undergoing MUA were younger (55.2 vs 65.3 years, P < .001) and had higher rates of current smoking (21.0% vs 7.3%, P < .001) and prior procedure (59.7% vs 40.4%, P = .002), most commonly arthroscopy; a control group of patients not requiring MUA, matched on the basis of these variables, was identified. While no difference in pre-TKA flexion existed across groups, final flexion in the early MUA group (106.7°) was equivalent to that of controls (115.6°), while final flexion in the late MUA group was not (101.3°, P = .001)., Conclusion: TKA patients undergoing MUAs were younger, more likely to be current smokers, and more likely to have undergone prior knee surgery. Even in patients with severe initial postoperative limitations in range of motion, MUA within 6 weeks may allow for final outcomes that are equivalent to those experienced by similar patients not requiring manipulation., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Through a process called perilacunar remodeling, bone-embedded osteocytes dynamically resorb and replace the surrounding perilacunar bone matrix to maintain mineral homeostasis. The vital canalicular networks required for osteocyte nourishment and communication, as well as the exquisitely organized bone extracellular matrix, also depend upon perilacunar remodeling. Nonetheless, many questions remain about the regulation of perilacunar remodeling and its role in skeletal disease. Here, we find that suppression of osteocyte-driven perilacunar remodeling, a fundamental cellular mechanism, plays a critical role in the glucocorticoid-induced osteonecrosis. In glucocorticoid-treated mice, we find that glucocorticoids coordinately suppress expression of several proteases required for perilacunar remodeling while causing degeneration of the osteocyte lacunocanalicular network, collagen disorganization, and matrix hypermineralization; all of which are apparent in human osteonecrotic lesions. Thus, osteocyte-mediated perilacunar remodeling maintains bone homeostasis, is dysregulated in skeletal disease, and may represent an attractive therapeutic target for the treatment of osteonecrosis.

Background: The coexistence of degenerative hip disease and spinal pathology is not uncommon with the number of surgical treatments performed for each condition increasing annually. The limited research available suggests spinal pathology portends less pain relief and worse outcomes after total hip arthroplasty (THA). We hypothesize that primary THA patients with preexisting lumbar spinal fusions (LSF) experience worse early postoperative outcomes., Methods: This study is a retrospective matched cohort study. Primary THA patients at 1 institution who had undergone prior LSF (spine arthrodesis-hip arthroplasty [SAHA]) were identified and matched to controls of primary THA without LSF. Early outcomes (<90 days) were compared., Results: From 2012 to 2014, 35 SAHA patients were compared to 70 matched controls. Patients were similar in age, sex, American Society of Anesthesiologist score, body mass index, and Charlson Comorbidity Index. SAHA patients had higher rates of complications (31.4% vs 8.6%, P = .008), reoperation (14.3% vs 2.9%, P = .040), and general anesthesia (54.3% vs 5.7%, P = .0001). Bivariate analysis demonstrated SAHA to predict reoperation (odds ratio, 5.67; P = .045) and complications (odds ratio, 4.89; P = .005). With the numbers available, dislocations (0% vs 2.8%), infections (0% vs 8.6%), readmissions, postoperative walking distance, and disposition only trended to favor controls (P > .05). Comparing controls to SAHA patients with <3 or ≥3 levels fused, longer fusions had increased cumulative postoperative narcotic consumption (mean morphine equivalents, 44.3 vs 46.9 vs 169.4; P = .001)., Conclusion: Patients with preexisting LSF experience worse early outcomes after primary THA including higher rates of complications and reoperation. Lower rates of neuraxial anesthesia and increased narcotic usage represent potential contributors. The complex interplay between the lumbar spine and hip warrants attention and further investigation., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The aim of this study was to examine the clinical characteristics of patients who required revision and the rate of early complications after revision for metal-on-metal total hip arthroplasty (MOM THA) and metal-on-polyethylene total hip arthroplasty (MOP THA). Matched cohorts were selected by retrospective review from a single-center database of revision THAs for failed MOM and MOP THAs from 2010 to 2014. A total of 140 hips in 140 patients comprised the study population; 39 revisions were performed for failed MOM THAs (MOM group), and 101 revisions were performed for failed MOP THAs (MOP group). Data included patient demographics, reason for revision, type of revision procedure, any complication within 90 days after surgery, admission type, and discharge disposition. Primary diagnosis, time from primary THA to revision, operative time, blood loss, and length of stay were reviewed. The analysis showed the time from the index primary procedure to first revision was earlier (P=.01) in the MOM group despite no significant intergroup differences in age, gender, primary diagnosis, or body mass index. Surgical morbidity, as indicated by operative time, blood loss, and length of stay, was lower in the MOM group. The stem was retained more often in the MOM group. There was no significant difference between the groups in overall complication rate. These findings indicate that when performed at an earlier time period before extensive soft tissue reaction to metal ions, revision following MOM THA is not associated with an increased complication rate compared with revision following MOP THA. [Orthopedics. 2017; 40(1):e164-e169.]., (Copyright 2016, SLACK Incorporated.)

Background: The practice of a surgeon performing procedures in two operating rooms during overlapping time frames has been described as concurrent surgery if critical portions occur simultaneously, or overlapping surgery if they do not. Although recent media reports have focused on the potential adverse effects of these practices, to our knowledge, there has been no previous research investigating outcomes of overlapping procedures in orthopaedic surgery., Methods: A retrospective review of an institutional clinical database from 2012 to 2015 was utilized to collect data from all surgical cases (including sports medicine, hand, and foot and ankle) performed at an ambulatory orthopaedic surgery center. Patient demographic characteristics, types of procedures, operating room time, procedure time, and 30-day outcomes including complications, unplanned hospital readmissions, unplanned reoperations, and emergency department visits were collected. The amount of overlap time between cases was also analyzed. Pearson chi-square tests, Student t tests, and logistic regression were used for statistical analysis., Results: Of 3,640 cases performed, 68% were overlapping procedures and 32% were non-overlapping. There was no difference in the mean age, sex, body mass index, American Society of Anesthesiologists rating, or Charlson Comorbidity Index between patients who had overlapping procedures and those who did not. Comparison of overlapping surgery cases and non-overlapping surgery cases revealed no difference in the mean procedure time (70.7 minutes compared with 72.8 minutes; p = 0.116) or total operating room time (105.4 minutes compared with 105.5 minutes; p = 0.949). Complications were tracked for 30 days after procedures and yielded a rate of 1.1% for overlapping surgeries and 1.3% for non-overlapping surgeries (p = 0.811). Stratification based on subspecialty surgery also demonstrated no difference in complications between the cohorts. Fifty percent of overlapping cases overlapped by <1 hour of operating room time, but 7% overlapped by >2 hours. The rate of complications was found to have no association with the amount of overlap between cases (p = 0.151)., Conclusions: Overlapping surgery yields equivalent patient operating room time, procedure time, and 30-day complication rates as non-overlapping surgery in the ambulatory orthopaedic setting. Further investigation is warranted for inpatient orthopaedic procedures and across all orthopaedic subspecialties., Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence., (Copyright © 2016 by The Journal of Bone and Joint Surgery, Incorporated.)