Search

To evaluate socioeconomic factors affecting whether a patient undergoes rotator cuff repair after a diagnosis of a rotator cuff tear. From 2009 through 2018, claims for adult (≥18 years of age) patients who were diagnosed with a primary rotator cuff injury were identified in the New York Statewide Planning and Research Cooperative System (SPARCS) database via International Classification of Diseases (ICD)—9th Revision—Clinical Modification (CM) and ICD-10-CM diagnostic codes. SPARCS is a comprehensive all-payer database collecting all inpatient and outpatient pre-adjudicated claims in New York. ICD-9-CM and ICD-10-CM codes were used to identify the initial diagnosis for each patient. Current Procedural Terminology codes were used to identify subsequent rotator cuff surgery. The procedures identified were linked with the initial diagnosis, and patients were noted as either having or not having rotator cuff surgery. Logistic regression analysis was performed for variables including age, sex, race, Social Deprivation Index (SDI), Charlson Comorbidity Index, and primary insurance type to determine the effect of patient factors on the likelihood of having surgery after a diagnosis of rotator cuff injury. Of the 67,584 rotator cuff patients included in the analysis, 19,770 (29.3%) of the patients underwent surgical intervention. From the logistic regression, females relative to males (odds ratio [OR] = 0.798, P <.0001), increased SDI (OR = 0.994, p <.0001), African American compared with White race (OR = 0.694, P <.0001), Asian compared with White (OR = 0.832, P <.0001), Hispanic compared with White (OR = 0.693, P <.0001), other race (OR = 0.58, P <.0001), those with Medicare (OR = 0.601, P <.0001) or Medicaid (OR = 0.614, P <.0001) relative to private insurance, and self-pay relative to private insurance (OR = 0.727, P <.0001) were all associated with decreased odds of undergoing rotator cuff surgery. Older patients (OR = 1.012, P <.0001) and Workers' Compensation relative to private insurance (OR = 1.664, P <.0001) had increased odds of undergoing surgery. The results of the current study identified disparities in the likelihood of undergoing rotator cuff repair after a diagnosis of a rotator cuff tear based on patient demographic and socioeconomic factors. Individuals with higher SDI; African American, Asian, Hispanic, or other non-White races; and those with Medicare, Medicaid, or self-pay insurance had decreased odds of surgery, whereas older age and Workers' Compensation insurance were associated with increased odds of undergoing surgery. Level IV, retrospective case series [ABSTRACT FROM AUTHOR]

Posterior glenohumeral instability represents a wide spectrum of pathoanatomic processes. A key consideration is the interplay between the posterior capsulolabral complex and the osseous anatomy of the glenoid and humeral head. Stability is dependent upon both the presence of soft tissue pathology (eg, tears to the posteroinferior labrum or posterior band of the inferior glenohumeral ligament, glenoid bone loss, reverse Hill Sachs lesions, and pathologic glenoid retroversion or dysplasia) and dynamic stabilizing forces. This review highlights unique pathoanatomic features of posterior shoulder instability and associated biomechanics that may exist in patients with posterior glenohumeral instability. [ABSTRACT FROM AUTHOR]

To assess the biomechanical utility of a posterior acromial bone block (PABB) for the treatment of posterior glenohumeral instability. Ten fresh-frozen cadaveric specimens were obtained based upon an a priori power analysis. A 2.5-cm scapular spine autograft was harvested from all shoulders. A custom robot device was used to apply a 50-N compressive force to the glenohumeral joint. The humeral head was translated 10 mm posteroinferiorly at 30 degrees from the center of the glenoid at a rate of 1.0 mm/s in 6 consecutive conditions: (1) intact specimen, (2) intact with PABB, (3) posterior capsulolabral tear, (4) addition of the PABB, (5) removal of the PABB and repair of the capsulolabral tear (LR), and (6) addition of the PABB with LR. The maximum force required to obtain this translation was recorded. Paired t tests were performed to compare relevant testing conditions. Ten cadavers with a mean ± SD age of 54.4 ± 13.1 years and mean ± SD glenoid retroversion of 6.5 ± 1.0 degrees were studied. The PABB provided greater resistance force to humeral head translation compared to the instability state (instability, 29.3 ± 15.3 N vs PABB, 47.6 ± 21.0 N; P =.001; 95% confidence interval [CI], –27.6 to –10.0). When comparing PABB to LR, the PABB produced higher resistance force than LR alone (PABB, 47.6 ± 21.0 N; LR, 34.2 ± 20.5 N; P =.012; 95% CI, –23.4 to –4.1). An instability lesion treated with the PABB, with LR (P =.056; 95% CI, –0.30 to 20.4) or without LR (P =.351; 95% CI, –6.8 to 15.7), produced resistance forces similar to the intact specimen. A PABB is biomechanically effective at restoring the force required to translate the humeral head posteriorly in a cadaveric, posterior glenohumeral instability model. A posterior acromial bone block is a biomechanically feasible option to consider in patients with recurrent posterior instability. Augmentation of the posterior acromion may be a biomechanically feasible option to treat posterior shoulder instability. [ABSTRACT FROM AUTHOR]

As the utilization and success of reverse total shoulder arthroplasty (RTSA) have continued to grow, so have its surgical indications. Despite the adoption of RTSA for the treatment of glenohumeral osteoarthritis (GHOA) with an intact rotator cuff and irreparable massive rotator cuff tears (MCTs) without arthritis, the literature remains sparse regarding the differential outcomes after RTSA among these varying indications. Thus, the purpose of this study was to examine the postoperative clinical outcomes of RTSA based on indication. A retrospective review of 2 large institutional databases was performed to identify all patients who underwent RTSA between 2015 and 2019 with minimum 2-year follow-up. Patients were stratified by indication into 3 cohorts: GHOA, rotator cuff tear arthropathy (CTA), and MCT. Baseline demographic characteristics were collected to determine differences between the 3 cohorts. Clinical outcomes were measured preoperatively and postoperatively, including active range of motion, American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation score, and visual analog scale pain score. Multivariate linear regression was performed to determine the factors independently predictive of the postoperative ASES score. A total of 625 patients (383 with GHOA, 164 with CTA, and 78 with MCTs) with a mean follow-up period of 33.4 months were included in the analysis. Patients with GHOA had superior ASES scores (85.6 ± 15.7 vs. 76.6 ± 20.8 in CTA cohort [ P <.001] and 75.9 ± 19.9 in MCT cohort [ P <.001]), Single Assessment Numeric Evaluation scores (86 ± 20.9 vs. 76.7 ± 24.1 in CTA cohort [ P <.001] and 74.2 ± 25.3 in MCT cohort [ P <.001]), and visual analog scale pain scores (median [interquartile range], 0.0 [0.0-1.0] vs. 0.0 [0.0-2.0] in CTA cohort [ P <.001] and 0.0 [0.0-2.0] in MCT cohort [ P <.001]) postoperatively. Postoperative active forward elevation (P <.001) and improvement in active external rotation (P <.001) were greatest in the GHOA cohort compared with other indications. Multivariate linear regression demonstrated that the factors independently associated with the postoperative ASES score included a diagnosis of GHOA (β coefficient, 7.557 [ P <.001]), preoperative ASES score (β coefficient, 0.114 [ P =.009]), female sex (β coefficient, −4.476 [ P =.002]), history of surgery (β coefficient, −3.957 [ P =.018]), and postoperative complication (β coefficient, −13.550 [ P <.001]). RTSA for the treatment of GHOA generally has superior patient-reported and functional outcomes when compared with CTA and MCTs without arthritis. Long-term follow-up is needed to identify the lasting implications of such outcome differences. [ABSTRACT FROM AUTHOR]

In the United States, the use of testosterone therapy has increased over recent years. Anabolic steroid use has been associated with tendon rupture, although there is a paucity of evidence evaluating the risk of biceps tendon injury (BTI) with testosterone therapy. The aim of this study was to quantify the risk of BTI after the initiation of testosterone therapy. This was a retrospective cohort study using the PearlDiver database. Records between 2011 and 2018 were queried to identify patients aged 35-75 years who filled a testosterone prescription for a minimum of 3 months. A control group was created, comprising patients aged 35-75 years who had never filled a prescription for exogenous testosterone. International Classification of Diseases, Ninth Revision , International Classification of Diseases, Tenth Revision , and Current Procedural Terminology codes were used to identify patients with distal biceps injuries and those undergoing surgical repair. Three matching processes were completed: one for the overall cohort, one for the cohort comprising only male patients, and one for the cohort comprising only female patients. Each cohort was matched to its control on age, sex, Charlson Comorbidity Index, diabetes, tobacco use, and osteoporosis. Multivariate logistic regression was used to compare rates of distal BTI and subsequent surgical repair in the testosterone groups with their control groups. A total of 776,974 patients had filled a prescription for testosterone for a minimum of 3 consecutive months. In the overall matched analysis between the testosterone and control groups (n = 291,610 in both), the mean age of the patients was 53.9 years and 23.1% were women. Within 1 year of filling exogenous testosterone prescriptions for a minimum of 3 consecutive months, 650 patients experienced a distal BTI compared with 159 patients in the control group (odds ratio [OR], 4.10; 95% confidence interval [CI], 3.45-4.89; P <.001). At any time after testosterone therapy, patients with testosterone use were more than twice as likely to experience a distal BTI as their matched controls (OR, 2.07; 95% CI, 1.94-2.38). Patients who filled prescriptions for testosterone were more likely to undergo surgical repair within a year of the injury compared with the control group. A similar trend was seen in the cohort comprising male patients (OR, 1.63; 95% CI, 1.29-2.07). Patients with prior prescription testosterone exposure have an increased rate of BTI and biceps tendon repair compared with patients without such exposure. This finding provides insight into the risk profile of testosterone therapy, and doctors should consider counseling patients about this risk, particularly male patients. [ABSTRACT FROM AUTHOR]

With the increasing utilization of total knee arthroplasty (TKA) in a continually aging US population, the number of patients who have low bone mineral density who undergo TKA may concomitantly increase. This study aimed to assess the rates of short-term complications following TKA in patients who did and did not have a recent history of a prior fragility fracture. A matched retrospective cohort study analyzing 48,796 patients was performed using a national database to determine the impact of a preceding fragility fracture on rates of short-term complications following TKA. The rates of complications at 1 and 2 years post-TKA were analyzed using multivariate logistic regressions. Prior fragility fracture was associated with increased rates of 1-year hospital readmissions (hazard ratio = 1.30, 95% CI, 1.22-1.38), periprosthetic fractures (odds ratio [OR] = 2.72, 95% CI, 1.89-3.99), non–infection-related revisions (OR = 1.32, 95% CI, 1.09-1.60), secondary fragility fractures (OR = 4.62, 95% CI, 4.19-5.12), prosthesis dislocations (OR = 1.76, 95% CI, 1.22-2.56), prosthesis instabilities (OR = 1.64, 95% CI, 1.25-2.15), and periprosthetic infections (OR = 1.49, 95% CI, 1.29-1.71), with similar trends in implant-related complications also seen at the 2-year mark. Patients who filled a prescription for osteoporosis pharmacotherapy had clinically similar rates of these complications compared to those who did not. Sustaining a fragility fracture prior to TKA is associated with an increased risk of hospital readmission and significant implant-related postoperative complications, potentially increasing the morbidity and mortality of TKA in these patients. [ABSTRACT FROM AUTHOR]

Although reverse total shoulder arthroplasty (RSA) is considered a safe surgical option in elderly patients, large-scale analyses of complications and mortality after RSA in patients 80 years and older are scarce. The goals of the current study were to identify revision, complication, and early mortality rates after RSA in patients 80 years and older and compare these to younger patients. The PearlDiver Database, which contains services rendered to Medicare, Medicaid, and commercial insurance patients, was queried for patients undergoing RSA using International Classification of Diseases, Ninth/Tenth Revision (ICD-9 / ICD-10) procedure codes. Patients were separated into 2 groups based on their age: 80 years and older and <80 years of age. The incidence of revision arthroplasty, medical, and surgical complications after RSA were extracted. Multivariate regression was used to compare revision arthroplasty and complication rates between groups. Statistical significance was set at P <.05. A total of 29,430 cases of RSA were included, with 486 cases in patients 80 years and older (median age, 80 years; age range, 2 years). Patients 80 years and older had 1- and 2-year revision rates of 3.9% and 5.1%, compared with the younger cohort at 3.0% and 3.1%, respectively. In patients 80 years and older, there were higher rates of deep venous thrombosis (DVT) (odds ratio [OR] 2.87, 95% CI 1.5-4.97), urinary tract infection (OR 1.42, 95% CI 1.01-1.94), acute renal failure (OR 2.18, 95% CI 1.44-3.17), and pneumonia (OR 1.75, 95% CI 1.09-2.68) within 90 days postoperatively. Ninety-day surgical complications were similar between the cohorts; however, younger patients experienced higher rates of dislocation, stiffness, periprosthetic fracture, and implant complications 1 year postoperatively. Patients 80 years and older had a significantly higher 90-day mortality rate at 2.7% compared with 1.5% in younger patients (P =.002). RSA is a generally safe procedure even in patients 80 years and older, with low complication and revision rates. Patients 80 years and older had higher early mortality and medical complication rates, including DVT, renal failure, and pneumonia than patients <80 years of age. However, patients 80 years and older had lower rates of dislocation, periprosthetic fracture, and implant-related complication at 1 year postoperatively. [ABSTRACT FROM AUTHOR]

Background: Supination adduction ankle fractures are unique among rotational ankle fractures as plate constructs are more commonly used than independent screws for medial malleolar fixation. The purpose of this study was to compare fracture displacement between plate fixation to a novel screw-only construct using a cadaveric biomechanical early-weightbearing model for the treatment of vertical medial malleolus fractures. Methods: Six nonosteoporotic fresh-frozen cadaver shanks and feet in matched pairs underwent a vertical osteotomy of the medial malleolus to simulate the supination adduction type injury. Osteoporosis was measured using DEXA scans. One specimen from each pair was fixed with a one-third tubular buttress plate and the other with screw-only fixation. The specimens were then axially loaded for 100 000 cycles to simulate protected weightbearing, and subsequently loaded to failure in supination. Stiffness, fracture displacement, and load to failure were recorded. Statistical significance was set at P <.05. Results: There were no measurable differences in displacement between the 2 constructs during axial cyclic loading after 100 000 cycles (plate, 0.74 ± 0.09 mm; screws, 0.79 ± 0.18 mm; P =.225). During supination and axial load to failure, the plate outperformed the screw construct. For load to failure (2 mm displacement) at the fracture site, the plate group failed at 716 ± 240 N, whereas the screw group failed at 567 ± 237 N (P =.015). During load to catastrophic failure, the plate group outperformed the screw group (plate, 6011 ± 1646 N; screws, 4578 ± 1837 N; P =.002). Conclusion: For vertical medial malleolar fractures, the screw-only construct demonstrated no statistical difference when compared to buttress plating for cyclical axial loading, simulating early weightbearing in a boot. However, buttress plating is 21% to 24% stronger than the screw-only fixation construct in overall strength and prevention of catastrophic failure when loading in a supinated position. Clinical Relevance: The screw-only construct is biomechanically similar to a buttress plate when simulating early protected weightbearing. This suggests that early weightbearing as tolerated in a controlled ankle motion boot beginning 2 weeks postoperatively is mechanically safe for this fracture pattern and does not result in unacceptable amounts of fracture displacement. This construct may be useful as a less invasive treatment modality for the treatment of vertical medial malleolus fractures in select patients. [ABSTRACT FROM AUTHOR]

Introduction: During the emergence of the SARS-CoV-2 (COVID-19) pandemic, there were substantial changes in United States (U.S.) emergency department (ED) volumes and acuity of patient presentation compared to more recent years. Thus, the purpose of this study was to characterize the incidence of specific upper extremity (UE) injuries presenting to U.S. EDs during the COVID-19 pandemic and analyze trends across age groups and rates of hospital admission compared to years prior.Methods: The National Electronic Injury Surveillance System (NEISS) database was queried to identify patients who presented to U.S. EDs for an UE orthopaedic injury between 2016 and 2020. Chi-square analysis and logistic regression were used to assess for differences in ED presentation volume and hospital admissions between pre-pandemic (2016 through 2019) and during-pandemic (2020) times.Results: These queries returned 285,583 cases, representing a total estimate of 10,452,166 injuries presenting to EDs across the U.S. The mean incidence of UE orthopaedic injuries was 640.2 (95% CI, 638.2-642.3) injuries per 100,000 person-years, with the greatest year to year decrease in incidence occurring between 2019 and 2020 (20.1%). The largest number of estimated admissions occurred in 2020, with a total 135,018 admissions (95% CI, 131,518-138,517), a 41.6% increase from the average number of admissions between 2016 and 2019.Conclusion: There was a 20.1% decrease in the incidence of UE orthopaedic injuries presenting to EDs after the start of the COVID-19 pandemic with a concomitant 41.2% increase in the number of hospital admissions from the ED in 2020 compared to recent pre-pandemic years. We speculate that at least some elective, semi-elective or urgent ambulatory surgeries were canceled or delayed due to the pandemic and were subsequently directed to the ED for admission. Regardless of the cause of increased UE orthopaedic admissions, policy planners and administrators should be aware of the additional stresses placed on already burdened ED and inpatient services.Level Of Evidence: Level III - Retrospective Cohort Study. [ABSTRACT FROM AUTHOR]

The cellular mechanisms underlying excess scar tissue formation in arthrofibrosis following total knee arthroplasty (TKA) are well-described. Angiotensin receptor blockers (ARB), particularly losartan, is a commonly prescribed antihypertensive with demonstrated antifibrotic properties. This retrospective study aimed to assess the rates of 1- and 2-year postoperative complications in patients who filled prescriptions for ARBs during the 90 days after TKA. Patients undergoing primary TKA were selected from a large national insurance database, and the impact of ARB use after TKA on complications was assessed. Of the 1,299,106 patients who underwent TKA, 82,065 had filled at least a 90-day prescription of losartan, valsartan, or olmesartan immediately following their TKA. The rates of manipulation under anesthesia (MUA), arthroscopic lysis of adhesions (LOA), aseptic loosening, periprosthetic fracture, and revision at 1 and 2 years following TKA were analyzed using multivariable logistic regressions to control for various comorbidities. ARB use was associated with decreased rates of MUA (odds ratio [OR] = 0.94, 95% confidence interval (CI), 0.90 to 0.99), arthroscopy/LOA (OR = 0.86, 95% CI, 0.77 to 0.95), aseptic loosening (OR = 0.71, 95% CI, 0.61 to 0.83), periprosthetic fracture (OR = 0.58, 95% CI, 0.46 to 0.71), and revision (OR = 0.79, 95% CI, 0.74 to 0.85) 2 years after TKA. ARB use throughout the 90 days after TKA is associated with a decreased risk of MUA, arthroscopy/LOA, aseptic loosening, periprosthetic fracture, and revision, demonstrating the potential protective abilities of ARBs. Prospective studies evaluating the use of ARBs in patients at risk for postoperative stiffness would be beneficial to further elucidate this association. [ABSTRACT FROM AUTHOR]

Hypothesis Grammont-style reverse shoulder arthroplasty (RSA) has an increased risk of nerve injury compared with anatomic total shoulder arthroplasty (TSA) due to arm lengthening. We hypothesized that an RSA with a lateralized glenosphere and 135° neck-shaft angle would reduce humeral lengthening and decrease the risk of nerve injury to the level of a TSA. Methods The study prospectively enrolled 50 consecutive patients undergoing RSA (n = 30) or TSA (n = 20) as determined by a power analysis based on previous research for our institution. Intraoperative neuromonitoring was used to detect nerve alerts during 4 distinct stages of the procedure. Preoperative and postoperative arm lengths were measured on scaled radiographs. Patients were examined immediately postoperatively and at follow-up visits for neurologic complications. Results Mean motor and sensory nerve alerts per case were similar for TSA and RSA (motor: TSA, 1.5 ± 2; RSA, 1.5 ± 2; P =.96; sensory: TSA, 0.6 ± 0.9; RSA, 0.2 ± 0.6; P =.06). The mean change in arm length was 3 ± 7 mm in the TSA cohort vs. 14 ± 7 mm in the RSA cohort (P =.0001). Temporary neurologic changes postoperatively were noted in 1 TSA and 1 RSA patient, amounting to a 4% incidence of nerve injury. Conclusions An RSA design with a lateralized glenosphere and a lower neck-shaft angle decreases arm lengthening compared with the Grammont design. The reduction in lengthening appears to eliminate the historically increased risk of neurologic injury associated with RSA relative to TSA. [ABSTRACT FROM AUTHOR]

Background Computed tomography (CT) scan is the standard for the preoperative assessment of glenoid version and morphology before total shoulder arthroplasty. However, the capacity of magnetic resonance imaging (MRI) to visualize bone morphology has improved with advancing technology. The purpose of this study was to compare the accuracy of MRI to CT for assessment of glenoid version and Walch classification. Methods Three fellowship-trained shoulder surgeons assessed glenoid version and Walch classification of 30 patients with primary shoulder osteoarthritis who received both CT and MRI scans before total shoulder arthroplasty. Version measurements, Walch classification, and observer agreement were compared. Results Mean glenoid version was −15.5° and −18.6° by CT and MRI, respectively ( P  = .17). Interobserver reliability coefficients were good for both imaging modalities (CT, 0.73; MRI, 0.62). Intraobserver coefficients were good to excellent for CT (range, 0.76-0.87) and good for MRI (range, 0.75-0.79). For Walch classification, interobserver reliability for both modalities was merely fair, whereas intraobserver reliability was moderate to good. Although identification of type A1, A2, and B1 was nearly identical between CT and MRI, there was observer disagreement on type B2 ( P  = .001) and C glenoids ( P  = .03). Specifically, MRI underidentified type B2 and overidentified type C compared with CT. Conclusions MRI is largely comparable to CT scan for evaluation of the glenoid, with similar measurements of version and identification of less extreme Walch glenoids. However, MRI is less accurate at distinguishing between type B2 and C glenoids. [ABSTRACT FROM AUTHOR]

Background Patient-reported outcome measures (PROMs) are valuable tools for quantifying outcomes of orthopedic surgery. However, when baseline scores are not obtained, there is considerable controversy about whether PROMs can be administered retrospectively for patients to recall their preoperative state. We investigated the accuracy of patient recall after total shoulder arthroplasty (TSA) using the American Shoulder and Elbow Surgeons (ASES) assessment score. Methods Recalled ASES scores were collected postoperatively at 6 weeks, 3 months, 6 months, and 12 months from 169 patients who previously completed baseline scores before TSA. The ASES total score was divided into its two subcomponents: functional ability and visual analog scale (VAS) for pain. We compared preoperative and recalled scores for each subcomponent and the total ASES score. Results Recalled ASES function scores were comparable to corresponding preoperative scores across all time points (analysis of variance, P  = .21), but recalled VAS pain was significantly higher at all time points beyond 6 weeks after surgery ( P  = .0001 at 3 months; P  = .005 at 6 months; and P  = .001 at 12 months). As a result, the ASES total score was only comparable at 6 weeks after surgery ( P  = .39) and differed at all time points thereafter. Conclusion Patients are able to recall preoperative function with considerable accuracy for up to 12 months after TSA. However, beyond 6 weeks postoperatively, patients recall having worse pain than they originally reported, and recalled ASES total scores are unreliable as a result. [ABSTRACT FROM AUTHOR]

Given the prevalence of obesity in the United States, much of the adult reconstruction literature focuses on the effects of obesity and morbid obesity. However, there is little published data on the effect of being underweight on postoperative outcomes. This study aimed to examine the risk of low body mass index (BMI) on complications after total hip arthroplasty (THA). A large national database was queried between 2010 and 2020 to identify patients who had THAs. Using International Classification of Disease codes, patients were grouped into the following BMI categories: morbid obesity (BMI>40), obesity (BMI 30 to 40), normal BMI (BMI 20 to 30), and underweight (BMI<20). There were 58,151 patients identified, including 2,484 (4.27%) underweight patients, 34,710 (59.69%) obese patients, and 20,957 (36.04%) morbidly obese patients. Control groups were created for each study group, matching for age, sex, and a comorbidity index. Complications that occurred within 1 year postoperatively were isolated. Subanalyses were performed to compare complications between underweight and obese patients. Statistical analyses were performed using Pearson Chi -squares. Compared to their matched control group, underweight patients showed increased odds of THA revision (Odds Ratio (OR) = 1.32, P =.04), sepsis (OR = 1.51, P =.01), and periprosthetic fractures (OR = 1.63, P =.01). When directly comparing underweight and obese patients (BMI 30 and above), underweight patients had higher odds of aseptic loosening (OR = 1.62, P =.03), sepsis (OR = 1.34, P =.03), dislocation (OR = 1.84, P <.001), and periprosthetic fracture (OR = 1.46, P =.01). Morbidly obese patients experience the highest odds of complications, although underweight patients also had elevated odds for several complications. Underweight patients are an under-recognized and understudied high risk arthroplasty cohort and further research is needed. [ABSTRACT FROM AUTHOR]