Summary

The purpose is to report minimum 5-year follow-up survivorship, patient-reported outcome scores (PROs), clinical benefit, and risk factors for conversion to total hip arthroplasty (THA) in the obese patient population following revision hip arthroscopy.

Abstract

Background

There is a paucity of literature reporting outcomes following revision hip arthroscopy in the obese patients.

Purpose

To report minimum 5-year follow-up survivorship, patient-reported outcome scores (PROs), clinical benefit, and risk factors for conversion to total hip arthroplasty (THA) in the obese patient population following revision hip arthroscopy.

Study Design: Case-series; Level of evidence, 4.

Methods

Data were prospectively collected and retrospectively reviewed for patients who underwent revision hip arthroscopy between April 2010 and August 2016. Inclusion criteria were having a body mass index = 30, baseline and minimum 5-year scores for the modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), Hip Outcome Score–Sports Specific Subscale (HOS-SSS), and Visual Analog Scale (VAS) for pain. Exclusion criteria were a Tönnis grade > 1, hip dysplasia, or were unwilling to participate. Survivorship was defined as non-conversion to THA. Clinical benefit was measured with the minimal clinically important difference (MCID). Survivors and non-survivors underwent further bivariate and regression analysis to determine predictors of conversion to THA.

Results

Twenty-four hips (80%) had minimum 5-year follow-up. The average follow-up was 83.9 ± 26.5 months and the average age was 39.3 ± 12.7 years. Survivorship was 75% and patients demonstrated significant improvement in all PROs (P < 0.01). Patients achieved rates of MCID for the mHHS, NAHS, HOS-SSS, and VAS at 70.6%, 94.1%, 86.7%, and 64.7, respectively. Age, ligamentum teres percentile, and acetabuloplasty were significant in the bivariate analysis for THA conversion. Age was identified as a significant variable for THA conversion in the regression analysis (P = 0.018, Odds Ratio: 1.297, 95% Confidence Interval [1.045 – 1.609]).

Conclusion

In this single surgeon case series study, obese patients who underwent revision hip arthroscopy reported a survivorship of 75% with significant improvement in all PROs and achieved MCID rates for the mHHS, NAHS, HOS-SSS, and VAS at 70.6%, 94.1%, 86.7%, and 64.7, respectively, at a minimum 5-year follow-up. Age was identified as a significant predictor in the regression and every additional year before surgery was identified as a 29.7% greater risk of conversion to THA.