Is semaglutide a better weight-management option than bariatric surgery for patients undergoing total knee arthroplasty?

BACKGROUND: Bariatric surgery has been associated with increased risks of revision surgery following total knee arthroplasty (TKA), raising concerns about its safety for weight management in this population. Semaglutide, a glucagon-like peptide-1 receptor agonist, has emerged as a promising pharmacologic alternative, though its impact on TKA outcomes remains underexplored. This study compares TKA outcomes between patients who have a history of bariatric surgery and semaglutide use. METHODS: A retrospective analysis of 19,135 TKA patients from 2012 to 2023 identified three cohorts: patients who used semaglutide (SU, n = 402), had bariatric surgery (BS, n = 418), and a BMI > 35 control group (C, n = 6,650). Demographics, BMI trends, 90-day complications, and revision rates were compared using statistical analyses, including Kaplan-Meier survivorship and multivariate logistic regression. RESULTS: Bariatric surgery patients experienced significantly more 90-day emergency department (ED) visits (7.9 [BS] vs. 5.7 [SU] vs. 4.0% [C], P < 0.001) and lower 10-year implant survival (90.3 [BS] vs. 94.5% [C], P = 0.039). Multivariate analysis demonstrated that a history of BS independently predicted increased odds of ED visits (OR 1.79, P = 0.005) and revision (OR 1.71, P = 0.028), while SU was not a significant predictor of adverse outcomes. The BS group achieved the largest preoperative BMI reduction (–1.8 kg/m²) vs. SU (–0.7 kg/m²) and controls (+ 2.1 kg/m²). Notably, the SU cohort regained 1.7 kg/m² within three years post-TKA. CONCLUSION: While semaglutide use before TKA was associated with only modest weight loss, it appeared safe and yielded favorable short-term outcomes. Bariatric surgery, though more effective for weight reduction, carried higher complication rates and inferior long-term implant survivorship. Further research is needed to clarify semaglutide’s long-term role in TKA patients with obesity. LEVEL OF EVIDENCE: III.