Obese Patients Treated by Hip Arthroscopy for Femoroacetabular Impingement Syndrome — 10-Year Functional Outcomes and Conversion Rates to Arthroplasty Compared With Normal-Weight Patients

Abstract

Background:

Obesity is a recognized adverse prognostic factor across various surgical interventions.

Purpose:

To evaluate long-term outcomes in patients with obesity who underwent hip arthroscopy for femoroacetabular impingement (FAI) and labral tears, compared with a control group with normal weight.

Study Design:

Retrospective cohort study; Level of evidence, 3.

Methods:

This was a prospectively matched cohort study. Data were analyzed for patients who underwent primary hip arthroscopy for FAI and labral tears between October 2008 and October 2013, with a body mass index (BMI) of ≥30 kg/m². Included patients had completed pre- and postoperative patient-reported outcomes (PROs) and visual analog scale (VAS) questionnaires at a minimum 10-year follow-up or a documented endpoint within the study time. Rates of revision surgery and survivorship were compared. A subanalysis was performed based on BMI subgroups, and a secondary subanalysis was conducted based on sex. Patients were propensity-matched to a control group of normal-weight patients (BMI, 20-24.99 kg/m²) in a 1 to 1 ratio by sex, age at surgery, acetabular Outerbridge grade, and capsular treatment.

Results:

A total of 266 patients were included in the study, with a mean follow-up time of 125.19 ± 43.07 months. The 2 groups demonstrated similar magnitudes of improvement at 10-year follow-up for the Non-Arthritic Hip Score (NAHS), Hip Outcome Score–Sport-Specific Subscale (HOS-SSS), and visual analog scale for pain (VAS-Pain), achieving comparable postoperative scores. The 2 groups achieved the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) for the modified Harris Hip Score (mHHS), NAHS, and HOS-SSS at similar rates (P <0.05). Obese patients had a higher frequency of conversion to total hip arthroplasty (THA) (odds ratio, 2.19 [95% CI, 1.17-4.13]; P < .05). Obese patients started with significantly lower baseline preoperative scores for all PROs. Patients with morbid obesity (BMI ≥40 kg/m²) reached the MCID and PASS for the mHHS at significantly lower rates. No differences in terms of PROs, complications, and secondary surgeries were found in the sex-based subanalysis.

Conclusion:

Hip arthroscopy for the treatment of FAI and labral tears in patients with obesity yielded significant and sustainable long-term improvements, which were equivalent to those of a benchmark matched control group of normal-weight patients. However, patients with obesity had >2-fold odds of conversion to THA. Patients with morbid obesity achieved clinical thresholds at lower rates and should therefore be approached with caution.