How Prominent Are Gender Bias, Racial Bias, and Score Inflation in Orthopaedic Surgery Residency Recommendation Letters? A Systematic Review.

INTRODUCTION: Letters of recommendation are considered an important factor in the holistic ranking of orthopaedic residency applications. The standardized letter of recommendation (SLOR) was introduced in 2017 in response to the inherent bias and limited comparative value of traditional LORs. It includes standardized questions about an applicant's orthopaedic qualifications, designed to enable fair comparisons among candidates. However, disparate and inconsistent findings have made it difficult to draw meaningful conclusions from individual studies on the SLOR and narrative letter of recommendation. QUESTION/PURPOSES: In this systematic review we asked: (1) What is the distribution of applicant SLOR rating among nine domains and summative scores? (2) Are there applicant characteristics associated with SLOR ratings? (3) Is there gender and racial bias in the SLOR and narrative letter of recommendation? METHODS: PubMed, EBSCO, and Google Scholar electronic databases were queried on March 20, 2023, to identify all studies evaluating SLOR and narrative letter of recommendations between January 1, 2017, and March 20, 2023. Articles that evaluated orthopaedic SLOR or narrative LORs were included. Systematic reviews, case reports, duplicate studies between databases, and grey literature such as abstracts and articles on preprint servers were excluded. Eight studies including 6179 applicants and 18,987 letters of recommendation were included in the final analysis. The applicant classes ranged from years 2014 to 2020. Two reviewers independently evaluated the quality of the included studies using the Joanna Briggs Institute (JBI) tool for cross-sectional studies. The mean JBI score of included studies was 7.4 out of a maximum of 8, with higher scores indicating better quality. The primary outcome was to determine the distribution of applicant SLOR rankings in their summative score. Summative scores were separated into ranked to match, top one-third, middle one-third, lower one-third, and not a fit. Four studies reported the summative SLOR scores of applicants. Our secondary study goal was to assess applicant characteristics associated with SLOR summative scores and assess any bias present in the SLOR or narrative recommendation. Five studies compared SLOR ratings across applicant characteristics including gender, race, USMLE Step 1 score, USMLE Step 2 score, Alpha Omega Alpha (AΩA) membership, clerkship grades, and publications. Gender and racial bias were also assessed across five studies. Four studies utilized a linguistic analysis software to search letters of recommendation for differences in word category use by gender and race. RESULTS: Studies consistently found that a higher percentage of candidates were identified in the top percentile blocks than is mathematically possible. For example, the two studies that tallied the proportion of candidates ranking in the top 10% of applicants found that 36% and 42% were rated as being in the top 10%. Similarly, articles found more than 87% of applicants scored in the top one-third. Studies had mixed results, but in general, they suggested that AΩA status, higher Step 1 scores, and more research publications have a slightly positive association with increased SLOR scores. We found no evidence of gender bias against women, and in fact, most studies evaluating word choices found word choices for women candidates generally were stronger. Similarly, no consistent disparities were identified in word categories utilized in SLORs based on applicant race. CONCLUSION: Most notably, a mathematically impossible proportion of applicants were counted in the top percentiles in letters of recommendation. This compromises readers' abilities to differentiate candidates. Factors like AOA status and research publications displayed a modest positive correlation with SLOR scores. Gender bias against women or candidates from racial minority groups was not evident. CLINICAL RELEVANCE: We suggest that group SLOR authorship, with a consensus assessment by clerkship or residency directors, should be considered. We also recommend the incorporation of mean and SD scores for each letter writer (or group) alongside their letters. Furthermore, studies indicate that submitting all four SLOR letters can substantially improve an applicant's chances of success. We advise students to choose strategically and submit the maximum allowable number of SLORs.

Five-Year Incidence of Progression to Osteoarthritis and Total Joint Arthroplasty in Patients Prescribed Glucagon-Like Peptide 1 Receptor Agonists.

BACKGROUND: Research has suggested that glucagon-like peptide-1 receptor agonists (GLP-1-RAs) may have therapeutic effects on osteoarthritis of the hip and knee, in addition to managing diabetes and obesity. However, there is a lack of understanding regarding the association between GLP-1-RA use and the diagnosis of osteoarthritis (OA) of the hip and knee. METHODS: A collaborative network analytics platform was queried for obese diabetic (n = 1,094,198), obese nondiabetic (n = 916,235), and nonobese diabetic (n = 157,305) patients who had an index visit between 2015 and 2017. Patients who had pre-existing hip and/or knee OA were excluded. A 1:1 propensity score matching was used to balance GLP-1-RA use in stratified cohorts for age, sex, race, body mass index, and hemoglobin A1c. The primary outcomes were rates of progression to hip OA, knee OA, major joint injections, total hip arthroplasty, and total knee arthroplasty. Cox proportional hazards models determined hazard ratios (HRs) between cohorts prescribed and not prescribed GLP-1-RAs. RESULTS: All patients had a five-year follow-up. Rates of progression to hip and knee OA were higher among the GLP-1-RA users in both obese diabetic (hip HR: 1.63, 95% confidence interval [CI]: 1.46 to 1.82; knee HR: 1.52, CI: 1.41 to 1.64) and nonobese diabetic (hip HR: 1.78, CI: 1.50 to 2.10; knee HR: 1.58, CI: 1.39 to 1.80) cohorts. These diabetic cohorts received higher rates of major joint injections, though there was no difference in rates of total hip arthroplasty or total knee arthroplasty. No differences in five-year outcomes were seen when comparing obese, nondiabetic patients who were prescribed GLP-1-RAs with obese, nondiabetic patients not exposed to GLP-1-RAs. CONCLUSIONS: This five-year analysis found a greater risk of progression to hip and knee OA among obese and non-obese diabetic GLP-1-RA users. Further studies should explore GLP-1-RA effects upon glucose management, weight loss, and lower extremity arthritis development. LEVEL OF EVIDENCE: III, retrospective cohort study.

Is Hospital-Based Outpatient Revision Total Knee Arthroplasty Safe? An Analysis of 2,171 Outpatient Aseptic Revision Procedures.

BACKGROUND: Outpatient primary total knee arthroplasty (TKA) has been well-established as a safe and effective procedure; however, the safety of outpatient revision TKA remains unclear. Therefore, this study utilized a large database to compare outcomes between outpatient and inpatient revision TKA. METHODS: An all-payor database was queried to identify patients undergoing revision TKA from 2010 to 2022. Patients who had diagnosis codes related to periprosthetic joint infection (PJI) were excluded. Outpatient surgery was defined as a length of stay < 24 hours. Cohorts were matched by age, sex, Elixhauser Comorbidity Index, comorbidities (diabetes, obesity, tobacco use), components revised (1-versus 2-component), and revision etiology. Medical complications at 90 days and surgical complications at 1 and 2 years postoperatively were evaluated through multivariate logistic regression. A total of 4,342 aseptic revision TKAs were included. RESULTS: No differences in patient characteristics, procedure type, or revision etiologies were seen between groups. The outpatient cohort had a lower risk of PJI (odds ratio (OR): 0.547, 95% confidence interval (CI): 0.337 to 0.869; P = .012), wound dehiscence (OR: 0.393, 95% CI: 0.225 to 0.658; P < .001), transfusion (OR: 0.241, 95% CI: 0.055 to 0.750; P = .027), reoperation (OR: 0.508, 95% CI: 0.305 to 0.822; P = .007), and any complication (OR: 0.696, 95% CI: 0.584 to 0.829; P < .001) at 90 days postoperatively. At 1 year and 2 years postoperatively, outpatient revision TKA patients had a lower incidence of revision for PJI (OR: 0.332, 95% CI: 0.131 to 0.743; P = .011 and OR: 0.446, 95% CI; 0.217 to 0.859; P = .020, respectively) and all-cause revision (OR: 0.518, 95% CI: 0.377 to 0.706; P < .001 and OR: 0.548, 95% CI: 0.422 to 0.712; P < .001, respectively). CONCLUSIONS: Our findings suggest that revision TKA can be safely performed on an outpatient basis in appropriately selected patients who do not have an increased risk of adverse events relative to inpatient revision TKA. However, we could not ascertain case complexity in either cohort, and despite controlling for several potential confounders, other less tangible differences could exist between groups.

Low-Dose Aspirin Is the Safest Prophylaxis for Prevention of Venous Thromboembolism After Total Knee Arthroplasty Across All Patient Risk Profiles.

BACKGROUND: The International Consensus Meeting on Venous Thromboembolism (ICM-VTE) in 2022 proclaimed low-dose aspirin as the most effective agent in patients across all risk profiles undergoing joint arthroplasty. However, data on large patient populations assessing trends in chemoprophylactic choices and related outcomes following total knee arthroplasty (TKA) remain scant. The present study was designed to characterize the clinical use of various chemoprophylactic agents in patients undergoing TKA and to determine the efficacy of aspirin compared with other agents in patient groups stratified by VTE risk profiles. METHODS: This study utilized a national database to determine the proportion of patients undergoing TKA who received low-dose aspirin versus other chemoprophylaxis between 2012 and 2022. VTE risk profiles were determined on the basis of comorbidities established in the ICM-VTE. The odds ratios (ORs) and 95% confidence intervals (CIs) between various classes of thromboprophylaxis in patients with high and low risk of VTE were calculated. The odds of deep-vein thrombosis (DVT), pulmonary embolus (PE), bleeding events, infections, mortality, and hospitalizations were also assessed in the 90-day postoperative period for propensity-matched cohorts receiving low-dose (81 mg) aspirin only versus other prophylaxis, segregating patients by VTE risk profile. RESULTS: A total of 126,692 patients undergoing TKA across 60 health-care organizations were included. The proportion of patients receiving low-dose aspirin increased from 7.65% to 55.29% between 2012 and 2022, whereas the proportion of patients receiving other chemoprophylaxis decreased from 96.25% to 42.98%. Low-dose-aspirin-only use increased to approximately 50% in both high-risk and low-risk populations but was more likely in low-risk populations (OR, 1.17; 95% CI, 1.15 to 1.20) relative to high-risk populations. Both low-risk and high-risk patients in the low-dose-aspirin-only cohorts had decreased odds of DVT, PE, bleeding, infections, and hospitalizations compared with other prophylaxis regimens. CONCLUSIONS: The findings of the present study on a very large population of patients undergoing TKA support the recent ICM-VTE statement by showing that low-dose aspirin is a safe and effective method of prophylaxis in patients across various risk profiles. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Association between abductor tears and hip pathology: A nationwide large cohort study.

Introduction: Although gluteal tears have been observed in a substantial percentage of total hip arthroplasty (THA) patients and hip osteoarthritis (OA) has been shown to alter the function of the gluteal muscles, the association between gluteal tears and hip OA has not been characterized. Therefore, we evaluated (1) the overlap between hip OA and gluteal tears, (2) the relative risks of gluteal tears in patients who have hip OA, and (3) gluteal tear-free survival after diagnosis or treatment for hip osteoarthritis. Methods: This retrospective study sourced data from TriNetX, a research network that aggregates data from over 92 million patients. Relative risks for gluteal tears were calculated for known risk factors for gluteal tears, age ≥45 years, female sex, and obesity, as well as for hip OA, hip injections, and THA. A subgroup analysis was performed utilizing a Cox proportional hazard model for patients who were diagnosed with hip OA, received a hip injection, or underwent THA in 2015 to assess gluteal tear-free survival over a 9-year timeframe. Results: There was a large degree of overlap between patients with hip OA and gluteal tears, as 17.9% of patients with hip OA and 27.5% of patients with a gluteal tear also had the other pathology. Hip OA was associated with a markedly increased risk of a gluteal tear compared to healthy controls (Relative risk: 26.75, 95% CI: 26.64-26.86). Upon controlling for the established risk factors of gluteal tears, patients with hip OA had a markedly more likely to subsequently be diagnosed with an abductor tear (Hazard ratio: 12.46, 95% CI: 11.75-13.22). Conclusion: Overall, these findings suggest a strong association between hip OA and the development of gluteal tears, in which further investigation is merited to determine the biomechanical pathophysiology underlying this potential relationship to inform prevention and treatment strategies.

Does rickets carry an increased risk of osteomyelitis and septic arthritis? An aggregated electronic health record data study.

To investigate the prevalence of osteomyelitis and septic arthritis in pediatric patients with rickets, compared to the general population. A retrospective cohort study was conducted using the TriNetX analytics network, which aggregates deidentified electronic health record data from over 105 million US patients. We queried pediatric patients with rickets, based on ICD-10-CM (International Classification of Diseases, Tenth Revision, Clinical Modification) encounter diagnoses. Patients with any ICD-10-CM encounter diagnoses of osteomyelitis or septic arthritis were reported. We established a control cohort of pediatric patients without rickets. Of 7337 pediatric patients (≤18 years old) with a rickets diagnosis, 96 [1.31%, 95% confidence interval (CI): 1.05%-1.57%] had a diagnosis of osteomyelitis and 28 (0.38%, 95% CI: 0.24%-0.52%) had a diagnosis of septic arthritis. In comparison, of the 17 240 604 pediatric patients without a rickets diagnosis, 16 995 (0.10%, 95% CI: 0.10%-0.10%) had a diagnosis of osteomyelitis and 8521 (0.05%, 95% CI: 0.05%-0.05%) had a diagnosis of septic arthritis. The relative risk for an osteomyelitis diagnosis in pediatric patients with a rickets diagnosis was 13.27 (95% CI: 10.86-16.23), while the relative risk for a septic arthritis diagnosis was 7.72 (95% CI: 5.33-11.18). Pediatric patients with a diagnosis of rickets have over 10- and 5-times higher relative risks for having a diagnosis of osteomyelitis and septic arthritis, respectively, compared to those without a diagnosis of rickets. This is the first study to explore musculoskeletal infections in rickets patients, highlighting the importance of clinicians being vigilant about these conditions.

Incidence of Sacroiliac Joint Pain Following Lumbar Fractures: A Retrospective-Cohort Study.

BACKGROUND: Sacroiliac joint (SIJ) pain commonly affects patients with low back pain and can arise from traumatic and degenerative causes. However, the incidence of SIJ pain following lumbar fractures is not well understood. METHODS: TriNetX, a national network of deidentified patient records, was retrospectively queried. The lumbar fracture cohort included 239,199 adults, while the no lumbar fracture group included 6,975,046 adults. Following a propensity-score match based on demographics and risk factors for SIJ, there were 239,197 patients in each cohort. The incidence of SIJ pain and clinical outcomes were analyzed from 1 day to 1 year following the index event. Moreover, the location and type of single-level lumbar fractures were reported. The incidence of SIJ pain for single-level fractures was compared using a χ2 goodness-of-fit. RESULTS: The lumbar fracture cohort was more likely to develop SIJ pain at 3 months (odds ratio [OR]: 5.3, 95% confidence interval [CI]: 4.8-5.9), 6 months (OR: 4.4, 95% CI: 4.1-4.8), and 1 year (OR: 3.9, 95% CI: 3.6-4.2) postfracture. Among single-level lumbar fractures, the incidence of SIJ pain at 1 month (P = 0.005), 6 months (P = 0.010), and 1 year (P = 0.003) varied significantly, with the highest incidence in the L5 cohort. CONCLUSIONS: Our findings suggest that lumbar fractures are a risk factor for developing SIJ pain. Moreover, the incidence of SIJ pain is greater following an L5 fracture than an L1 fracture. Further investigation is warranted to determine how the type and treatment of lumbar fractures affects the incidence of SIJ pain.

Low-Density Lipoprotein Cholesterol and Statin Usage Are Associated With Rates of Pseudarthrosis Following Single-Level Posterior Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To investigate the relationships of low-density lipoprotein cholesterol and statin usage with pseudarthrosis following single-level posterior or transforaminal lumbar interbody fusion (PLIF/TLIF). SUMMARY OF BACKGROUND DATA: Hypercholesterolemia can lead to atherosclerosis of the segmental arteries, which branch into vertebral bone through intervertebral foramina. According to the vascular hypothesis of disc disease, this can lead to ischemia of the lumbar discs and contribute to lumbar degenerative disease. Yet, little has been reported regarding the effects of cholesterol and statins on the outcomes of lumbar fusion surgery. MATERIALS AND METHODS: TriNetX, a global federated research network, was retrospectively queried to identify 52,140 PLIF/TLIF patients between 2002 and 2021. Of these patients, 2137 had high cholesterol (≥130 mg/dL) and 906 had low cholesterol (≤55 mg/dL). Perioperatively, 18,275 patients used statins, while 33,415 patients did not. One-to-one propensity score matching for age, sex, race, and comorbidities was conducted to balance the analyzed cohorts. The incidence of pseudarthrosis was then assessed in the matched cohorts within the six-month, one-year, and two-year postoperative periods. RESULTS: After propensity score matching, high-cholesterol patients had greater odds of developing pseudarthrosis six months [odds ratio (OR): 1.73, 95% confidence interval (CI): 1.28-2.33], one year (OR: 1.59, 95% confidence interval (CI): 1.20-2.10), and two years (OR: 1.57, 95% CI: 1.20-2.05) following a PLIF/TLIF procedure. Patients with statin usage had significantly lower odds of developing pseudarthrosis six months (OR: 0.74, 95% CI: 0.69-0.79), one year (OR: 0.76, 95% CI: 0.71-0.81), and two years (OR: 0.77, 95% CI: 0.72-0.81) following single-level PLIF/TLIF. CONCLUSIONS: The findings suggest that patients with hypercholesterolemia have an increased risk of developing pseudarthrosis following PLIF/TLIF while statin use is associated with a decreased risk. The data presented may underscore an overlooked opportunity for perioperative optimization in lumbar fusion patients, warranting further investigation in this area.

Is Penicillin Allergy a Clinical Problem? A Systematic Review of Total Joint Arthroplasty Procedures With Implications for Patient Safety and Antibiotic Stewardship.

BACKGROUND: Patients undergoing total joint arthroplasty (TJA) who report penicillin allergy (PA) are frequently administered second-line antibiotics, although recent evidence suggests that this may be unnecessary and could increase infection risk. Many institutions have aimed to improve antibiotic deployment via allergy testing and screening; however, there is little standardization to this process. This review aimed to evaluate (1) antibiotic selection in patients who report PA and assess the impact of screening and testing interventions, (2) rates of allergic reactions in patients who report PA, and (3) the association between reported PA and screening or testing programs and odds of surgical site infection or periprosthetic joint infection. METHODS: PubMed, EBSCOhost, and Google Scholar electronic databases were searched on February 4, 2023 to identify all studies published since January 1, 2000 that evaluated the impact of PA on patients undergoing TJA (PROSPERO study protocol registration: CRD42023394031). Articles were included if full-text manuscripts in English were available, and the study analyzed the impact of PA and related interventions on TJA patients. There were 11 studies evaluating 1,276,663 patients included. Interventions were compared via presentation of key findings regarding rates of clinically relevant or high-risk PA reported upon screenings or testings, cephalosporin utilizations, allergic reactions, and postoperative infections (surgical site infection and periprosthetic joint infection). RESULTS: All 6 studies found that PA screening and testing markedly increase the use of first-line antibiotics. Testing showed low rates of true allergy (0.7 to 3%) and allergic reaction frequency for patients who have reported PA receiving cephalosporins was between 0% and 2%. Although there were mixed findings across studies, there was a trend toward second-line antibiotic prophylaxis being associated with a slightly higher rate of infection in PA patients. CONCLUSIONS: Using PA screening and testing can promote antibiotic stewardship by safely increasing the use of first-line antibiotics in patients who have a reported PA. LEVEL OF EVIDENCE: Level III, Therapeutic Study.

Understanding the use of artificial intelligence for implant analysis in total joint arthroplasty: a systematic review.

INTRODUCTION: In recent years, there has been a significant increase in the development of artificial intelligence (AI) algorithms aimed at reviewing radiographs after total joint arthroplasty (TJA). This disruptive technology is particularly promising in the context of preoperative planning for revision TJA. Yet, the efficacy of AI algorithms regarding TJA implant analysis has not been examined comprehensively. METHODS: PubMed, EBSCO, and Google Scholar electronic databases were utilized to identify all studies evaluating AI algorithms related to TJA implant analysis between 1 January 2000, and 27 February 2023 (PROSPERO study protocol registration: CRD42023403497). The mean methodological index for non-randomized studies score was 20.4 ± 0.6. We reported the accuracy, sensitivity, specificity, positive predictive value, and area under the curve (AUC) for the performance of each outcome measure. RESULTS: Our initial search yielded 374 articles, and a total of 20 studies with three main use cases were included. Sixteen studies analyzed implant identification, two addressed implant failure, and two addressed implant measurements. Each use case had a median AUC and accuracy above 0.90 and 90%, respectively, indicative of a well-performing AI algorithm. Most studies failed to include explainability methods and conduct external validity testing. CONCLUSION: These findings highlight the promising role of AI in recognizing implants in TJA. Preliminary studies have shown strong performance in implant identification, implant failure, and accurately measuring implant dimensions. Future research should follow a standardized guideline to develop and train models and place a strong emphasis on transparency and clarity in reporting results. LEVEL OF EVIDENCE: Level III.

Increased risk of osteomyelitis and septic arthritis in osteogenesis imperfecta.

We investigated the prevalence of osteomyelitis and septic arthritis in individuals with osteogenesis imperfecta (OI) as compared to the general population. We performed a retrospective cohort study utilizing the TriNetX Analytics platform, a federated, aggregated electronic health record (EHR) research network containing national, deidentified EHR data. We queried patients with OI, based on encounter diagnoses. Patients in this group with any occurrence of osteomyelitis or septic arthritis were recorded. A control cohort was established to compare the prevalence in patients without OI. Of 8444 individuals with OI, 433 (5.13%) had encounter diagnoses for osteomyelitis and 61 (0.72%) had encounter diagnoses for septic arthritis. In comparison, of 79 176 436 patients without OI, 352 009 (0.44%) had encounter diagnoses for osteomyelitis, while 106 647 (0.13%) had encounter diagnoses for septic arthritis. The relative risk for osteomyelitis in OI patients was 11.53 (95% CI: 10.52-12.64), while the relative risk for septic arthritis was 5.36 (95% CI: 4.18-6.89). The relative risk for osteomyelitis in pediatric OI patients was 30.55 (95% CI: 24.35-38.28). To our knowledge, this is the first study investigating musculoskeletal infections in patients with OI, as well as the first to report the overall prevalence in the general population. Clinicians may benefit from a high index of suspicion for musculoskeletal infections in OI patients with corresponding symptoms. Further study is warranted to investigate if modifications to conventional diagnostic pathways and criteria are valuable in this population. Level of evidence: Retrospective Cohort Study - Level II.

Implant Selection Strategies for Total Joint Arthroplasty: The Effects on Cost Containment and Physician Autonomy.

BACKGROUND: With continued declines in reimbursement for total joint arthroplasty, health systems have explored implant cost containment measures to generate sustainable margins. This review evaluated how implementation of (1) implant price control programs, (2) vendor purchasing agreements, and (3) bundled payment models affected implant costs and physician autonomy in implant selection. METHODS: PubMed, EBSCOhost, and Google Scholar were searched to identify studies that evaluated the efficacy of total hip or total knee arthroplasty implant selection strategies. The review included publications between January 1, 2002, and October 17, 2022. The mean Methodological Index for Nonrandomized Studies score was 18.3 ± 1.8. RESULTS: A total of 13 studies (32,197 patients) were included. All studies implementing implant price capitation programs found decreased implant costs, ranging 2.2 to 26.1% and increased utilization of premium implants. Most studies found bundled payments models reduced total joint arthroplasty implant costs with greatest reduction being 28.9%. Additionally, while absolute single vendor agreements had higher implant costs, preferred single vendor agreements had reduced implant costs. When given price constraints, surgeons tended to select more premium implants. CONCLUSION: Alternative payment models that incorporated implant selection strategies saw reduced costs and surgeon utilization of premium implants. The study findings encourage further research on implant selection strategies, which must balance the goals of cost containment with physician autonomy and optimized patient care. LEVEL OF EVIDENCE: Level III.

Total Hip Arthroplasty Outcomes in Patients Who Have a History of Prior Radiation.

BACKGROUND: The purpose of this study was to assess the odds of developing medical and surgical adverse events following total hip arthroplasty (THA) in patients who have a history of radiation therapy (RT) for cancer. METHODS: A retrospective cohort study was conducted using a national database to identify patients who underwent primary THA (Current Procedural Terminology code 27130) from 2002 to 2022. Patients who had a prior RT were identified by International Classification of Diseases, Tenth Revision, Clinical Modification codes Z51.0 (encounter for antineoplastic RT), Z92.3 (personal history of irradiation), or Current Procedural Terminology code 101843 (radiation oncology treatment). One-to-one propensity score matching was conducted to generate 3 pairs of cohorts: 1) THA with/without a history of RT; 2) THA with/without a history of cancer; and 3) THA patients who have a history of cancer treated with/without RT. Surgical and medical complications were assessed at the 30-day, 90-day, and 1-year postoperative periods. RESULTS: Patients who have a history of RT had higher odds of developing anemia, deep vein thrombosis, pneumonia, pulmonary embolism, and prosthetic joint infection at all intervals. When controlling for a history of cancer, RT was associated with an increased risk of pulmonary embolism, heterotrophic ossification, prosthetic joint infection, and periprosthetic fracture at all postoperative time points. There was additionally an increased risk of aseptic loosening at 1 year (odds ratio: 2.0, 95% confidence interval: 1.2 to 3.1). CONCLUSION: These findings suggest that patients who have a history of antineoplastic RT are at an increased risk of developing various surgical and medical complications following THA.