Summary

Comparing minimum 5-year outcomes between patients who underwent staged bilateral hip arthroscopic surgery for FAI to a propensity-score matched unilateral hip arthroscopy control group

Abstract

Background

Bilateral hip symptoms are known to be a common finding in patients with femoroacetabular impingement (FAI) in the general population. Currently, there is a paucity of literature regarding midterm survivorship and outcomes in patients undergoing staged bilateral hip arthroscopy.

Purpose

The primary purpose of this study to compare minimum 5-year outcomes between patients who underwent staged bilateral hip arthroscopic surgery for FAI to a propensity-score matched unilateral hip arthroscopy control group and secondarily, to investigate the impact of time interval between staged bilateral procedures on PROs.
Study Design: Cohort study; Level of evidence 3.

Methods

Data from of patients who underwent primary hip arthroscopies at our institution from XXX TO XXX were retrospectively collected. Patients who underwent bilateral hip arthroscopy with minimum 5-year PROs 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), and patient were included. The bilateral cohort was propensity-matched 1:1 to a control group that underwent unilateral hip arthroscopy based on age, sex, and body-mass index (BMI). A further sub-analysis was performed to determine the time interval impact between procedures in lesser or greater than 3 months.

Results

115 patients (230 hips) were included with a mean age of 32.0 ± 13.6 years and BMI of 24.7 ± 5.1 kg/m2. All 230 hips that met the inclusion criteria were propensity-matched. No significant differences in demographic radiographic, or procedural data was found. Both groups showed significant improvements in mHHS, NAHS, HOS-SSS, and VAS at mínimum 5-year follow-up. The unilateral cohort had a significantly higher rate of achieving the minimally clinical important difference (MCID) for the NAHS (P =.003). Both cohorts showed similarly high rates of survivorship (97.4% vs 98.3%). In the sub-analysis, it was found that patient who underwent contralateral hip arthroscopy <3 months apart had higher improvement rates for mHHS, NAHS, and VAS (P =.016, P =.040, P =.005 respectively).

Conclusion

Patients who underwent unilateral and bilateral hip arthroscopic surgery for FAI achieved significant improvement in PROs at minimum 5-years follow-up, with comparable results between groups. After dividing the bilateral cohort by time between procedures, patients with <3 month interval had greater magnitude of improvement. A time interval lesser than 3 months was associated with two times higher likelihood of achieving PASS for mHSS, and MCID for NAHS.