Comparative analysis of Birmingham hip resurfacing: Minimum 2-year follow-up clinical outcomes in obese vs. non-obese populations.

Abstract

Background and objective: With obese individuals experiencing osteoarthritis (OA) at early stages of life, hip resurfacing (HR) has emerged as an alternative to arthroplasty. The purpose is to conduct a short-term analysis on patients with obesity who underwent primary HR for OA compared to a benchmark control group of non-obese patients.

Materials and methods: Patients with a body mass index (BMI) ≥ 30 kg/m2 who underwent HR from 2010 to 2021 were eligible for inclusion. Included patients had pre-operative and minimum 2-year follow-up for the Modified Harris Hip Score (mHHS), Hip Disability and Osteoarthritis Outcome Score Joint Replacement Score (HOOS-JR), Forgotten Joint Score (FJS), Visual Analog Scale for Pain (VAS), and patient satisfaction or reached an endpoint revision surgery during the study time frame. Patients were propensity matched in a 1:1 ratio based on approach, age, and follow-up time. Clinically relevant outcome thresholds, sports participation, acetabular cup placement, complications, and conversions to total hip arthroplasty (THA) were included in the analysis.

Results: Seventy patients were included. Obese patients displayed significant improvements across all patient reported outcomes (PROs) and high patient satisfaction at short-term follow-up that was comparable to the non-obese group. Both groups also showed a similar return to sport and acetabular cup placement and met clinically relevant thresholds at similar rates. The obese group, specifically patients with a BMI>35, exhibited higher complication and revision surgery rate.

Conclusions: HR in patients with obesity showed significant short-term improvements, allowing a high percentage of patients to return to sports. These results were equivalent to a benchmark control group of non-obese patients. Additionally, obese patients tended to have an increased risk of complications than non-obese patients, with a higher rate of conversion to THA. Level of EvidenceLevel of Evidence III.