Predictors of Clinical Outcomes After Hip Arthroscopy: A Prospective Analysis of 1038 Patients With Two-Year Follow-Up


      The purpose of this study was to evaluate clinical outcomes of hip arthroscopy in a prospective study and to analyze this cohort to identify predictive factors of improvement.


      Data was collected prospectively on all patients undergoing hip arthroscopy between February 2008 and June 2012. We included all patients undergoing hip arthroscopy who agreed to participate and completed four PRO instruments at minimum two-year follow-up, including the modified Harris Hip Score, (mHHS), Non-arthritic Hip Score (NAHS), Hip Outcome Score – Activities of Daily Living and Sports Subscale (HOS-ADL, HOS-SSS). The NAHS was selected as our primary outcome instrument. All patients with any previous hip conditions were excluded. We analyzed 34 preoperative and intraoperative variables using bivariate and multivariate analyses compared to NAHS scores.


      The cohort consisted of 1038 patients with a mean follow-up of 30.1 months (range: 24.0 – 61.2 months). The mean age of the group was 36.4 years (range: 13.2 – 76.4 years). All postoperative PRO scores showed significant improvement (p <0.001) at two years compared to preoperative scores. Bivariate analysis identified fifteen variables (seven categorical and eight continuous), and multivariate analysis identified 10 variables that were predictive of two-year postoperative NAHS scores. Preoperative NAHS, HOS-ADL, mHHS, age, duration of symptoms, body mass index (BMI), and revision hip arthroscopy were identified as predictive factors in both bivariate and multivariate analyses. The predictive value of preoperative NAHS was accentuated for patients with higher BMI.


      This study reports favorable clinical outcomes in the largest cohort of hip arthroscopies with minimum two-year follow-up in the literature to date. Factors identified as predictive in both bivariate and multivariate analyses included preoperative NAHS, Hip HOS-ADL, and mHHS, age, duration of symptoms, BMI, and revision hip arthroscopy. These predictive factors may be useful to the clinician in determining prognosis and operative indications for hip arthroscopy.