Excessive Femoral Anteversion Associated With Worse Clinical Outcomes Following Hip Arthroscopic Surgery and Higher Prevalence of Anteroinferior Labral Tears in Patients With Femoroacetabular Impingement Syndrome

PURPOSE: To compare intraoperative findings associated with instability and clinical outcomes after hip arthroscopic femoroacetabular impingement syndrome (FAIS) surgery in patients with normal anteversion (NA) and excessive femoral anteversion (EA). METHODS: Inclusion criteria were FAIS cases who underwent primary arthroscopic management from January 2016 to December 2019. Patients who met exclusion criteria, such as osteoarthritis (Tonnis grade ≧ 2), and patients with less than a 2-year follow-up were excluded. The remaining hips were divided into 2 groups: the NA group (femoral anteversion 10°-25°) and the EA group (femoral anteversion > 25°). Clinical outcomes were assessed using the International Hip Outcome Tool 12 (iHOT12), hip outcome score activity of daily living scale (HOS-ADL), hip outcome score activity of sports (HOS-SP), and modified Harris hip score (mHHS). Achievement rates for the patient acceptable symptomatic state (PASS) and the minimal clinically important difference (MCID) were also evaluated. Intraoperative findings suggestive of instability were analyzed. RESULTS: The NA group included 34 hips, while the EA groups included 16 hips. Anteroinferior labral tears were significantly more prevalent in the EA group (75% vs 29.4%; P = .0051). Postoperative PROMs at 2 years were significantly worse in the EA group for iHOT12 (79.1 vs 95.1, P = .0017), HOS-ADL (91.2 vs 98.5, P = .0224), HOS-SP (83.3 vs 100, P = .0049), and mHHS (86.9 vs 96.8, P = .002). Regarding some PROMs, PASS achievement rates were also significantly lower in the EA group (iHot12: 56.2% vs 88.2%; P = .024, HOS-ADL: 62.5% vs 94.1%; P = .009), while no statistical difference was observed in MCID achievement rates. Three reoperations occurred in patients with EA, with femoral anteversion angles of 29°, 32.5°, and 33.5°. CONCLUSIONS: Patients with EA had inferior outcomes of hip arthroscopy and a higher prevalence of anteroinferior labral tears. LEVEL OF EVIDENCE: Level III, retrospective comparative case series.