Background: Weight optimization methods in morbidly obese patients with a body mass index (BMI) of ≥40 kg/m² undergoing total knee arthroplasty (TKA) have shown mixed results. The purpose of this study was to evaluate the effect of perioperative use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in patients with a BMI of ≥40 kg/m² undergoing primary TKA. Methods: Using an administrative claims database, patients with morbid obesity undergoing primary TKA were stratified into GLP-1 RA use for 3 months before and after the surgical procedure (treatment group) and GLP-1 RA non-use (control group), and were matched on the basis of patient age, gender, diagnosis of type-2 diabetes mellitus, and Charlson Comorbidity Index (CCI). In addition, these groups were compared with a contemporaneous cohort of patients undergoing TKA with a BMI of 35.0 to 39.9 kg/m². Outcomes including infection, complications, revision, and readmission were compared between the matched cohorts. Results: There were significant decreases in the rates of 90-day periprosthetic joint infection (PJI) (1.0% compared with 1.8%; p = 0.037), any medical complications (10.6% compared with 12.7%; p = 0.033), pulmonary embolism (<0.4% compared with 0.6%; p = 0.050), and readmissions (5.3% compared with 8.9%; p < 0.001) in patients with a BMI of ≥40 kg/m² who were taking GLP-1 RA versus the control group who were not. There were no differences in the 2-year rates of surgical complications (p > 0.05) between these groups. Compared with obese patients (BMI of 35.0 to 39.9 kg/m²), patients who had a BMI of ≥40 kg/m² and were taking a GLP-1 RA did not have increased rates of infection or 90-day or 2-year complications (p > 0.05). Conclusions: GLP-1 RA administration for at least 90 days prior to and after primary TKA in patients with a BMI of ≥40 kg/m² was associated with reductions in the risks of 90-day PJI, any medical complications, and readmission. Additionally, the reduced complication rate that was achieved was similar to that of obese patients with a BMI of 35.0 to 39.9 kg/m² undergoing TKA. Randomized clinical trials are needed to define the true effect of these agents on clinical outcomes following TKA. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background: There is limited data evaluating the effect of obesity on outcomes following total ankle arthroplasty (TAA), especially in adequate sample sizes to detect impacts on patient-reported outcomes (PROs). The purpose of this study was to assess the effect of obesity on complication rates and PROs. Methods: This was a single-institution, retrospective study of 1093 primary TAA performed between 2001 and 2020. Minimum follow-up was 2 years. Patients were stratified by body mass index (BMI) into control (BMI = 18.5-29.9; n = 615), obesity class I (BMI = 30.0-34.9; n = 285), and obesity class II (BMI > 35.0; n = 193) groups. Patient information, intraoperative variables, postoperative complications, and PRO measures were compared between groups using univariable statistics. Multivariable Cox regression was performed to assess risk for implant failure. Mean follow-up was 5.6 years (SD: 3.1). Results: Compared to control and class I, class II patients had the lowest mean age ( P = .001), highest mean ASA score ( P < .001), and greatest proportion of female sex ( P < .001) and Black/African American race ( P = .005). There were no statistically significant differences in postoperative complications (infection, implant failure, or impingement) across the BMI classes ( P > .05). Preoperatively, class II had lower (worse) mean scores for Foot and Ankle Outcome Score pain and ADL subscales than controls (post hoc pairwise P < .001 for both). At final follow-up, both class II and class I had lower (worse) mean Short Musculoskeletal Function Assessment (post hoc pairwise P < .001 and P = .030, respectively) and 36-Item Short Form Health Survey scores (post hoc pairwise P < .001 and P = .005, respectively) than controls. Conclusion: At midterm follow-up, obesity was not associated with increased rates of complications after TAA. Patients with obesity reported worse musculoskeletal function and overall quality of life after TAA but there was no differential improvement in PROs across BMI classes. To our knowledge, this is the largest single-institution study to date examining the effect of obesity on outcomes after primary TAA. Level of Evidence: Level III, retrospective comparative study.