The Impact of Obesity on Total Hip Arthroplasty Outcomes when Performed by High Volume Surgeons - A Propensity Matched Analysis from a High-Volume Urban Center.

INTRODUCTION: Previous data suggest that obesity does not impact surgical outcomes following total knee arthroplasty performed by high-volume (HV) surgeons. However, this effect has yet to be studied in total hip arthroplasty (THA) patients. This study aimed to evaluate the impact of patient obesity on THA outcomes when surgery is performed by HV surgeons.

METHODS: A retrospective analysis of patients who underwent primary, elective THA between January 2012 and December 2022 with a HV surgeon (top 25% of surgeons by number of annual primary THA) was performed. Patients were stratified by their body mass index (BMI) into three cohorts: BMI ≥ 40 (morbidly-obese, MO), 30 ≤ BMI <40 (obese, OB), and BMI < 30 (non-obese, NO); and 1:1:1 propensity matched based on baseline characteristics. A total of 13,223 patients were evaluated, of which 669 patients were included in the final matched analysis (223 patients per group). The average number of annual THAs performed for HV surgeons was 171 cases.

RESULTS: The MO patients had significantly longer surgical times (P < 0.001) and hospital lengths of stay (P < 0.001). Rates of 90-day readmissions (P = 0.211), and all-cause, septic and aseptic revisions at the latest follow-up (P = 0.268, P = 0.903, and P = 0.168, respectively) were comparable between groups. In a sub-analysis for non-HV surgeons, MO patients had a significantly greater risk of revision (P = 0.021) and trended towards significantly greater readmissions (P = 0.056).

CONCLUSION: Clinical outcomes and complication rates after THA performed by a HV surgeon are similar regardless of patient obesity status. Patients who have MO may experience improved outcomes and reduced procedural risks if they are referred to HV surgeons.