Do the outcomes of hip arthroscopy for femoroacetabular impingement change over time?

BACKGROUND: The purpose of this study was to search for changes in functional outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) between short and medium-term follow-up. Secondary aims included reporting rates of revision surgery and total hip arthroplasty (THA) at medium-term follow-up. HYPOTHESIS: We hypothesised that patients' functional outcomes would improve between short and medium-term follow-up. PATIENTS AND METHODS: Consecutive patients undergoing hip arthroscopy with a diagnosis of femoroacetabular impingement with labral tears between February 2013 and June 2015 were included. Twelve item international hip outcome tool (iHOT-12) and EuroQol 5D-5L (EQ-5D) scores were collected preoperatively, at short-term and medium-term follow-up. Short-term scores were recorded at a minimum of one year postoperatively and medium-term scores at a minimum of five years postoperatively. Survivorship was assessed with Kaplan-Meier analysis. RESULTS: Short-term outcome data (at median follow-up 1.6 year, Interquartile range [IQR] 1-2.5) was available for 70 of 87 patients (80.5%) and medium-term outcome data (at median follow-up of 6.5 years, IQR 6-7.1) was available for 68 patients (78.2%). Median age at the time of surgery was 31 years (IQR 25-37). The median iHOT-12 scores at short and medium-term follow-up were 72 (IQR 48.75-91.25) and 85.8 (IQR 66.7-96.7) respectively (p<0.001). Medium-term survivorship was 91.2%. Survivorship following labral repair was 94.2%, and 81.3% following labral debridement (p=0.09). DISCUSSION: Patients undergoing hip arthroscopy for FAI reported continued improvement in iHOT-12 scores between short and medium-term follow-up. Medium-term survivorship following FAI surgery may be greater when the labrum is repaired, although comparisons are limited by their differing indications. Conversion to THA was low with just 4 patients (4.6%) undergoing or being listed for THA at final follow-up. LEVEL OF EVIDENCE: IV, Case series.