FP9.1 Pre-operative radiographic markers and their risk prediction of symptomatic hip capsule failure following hip arthroscopy
Abstract
Abstract ICLB09 - The Revision Playbook: Advanced Execution and Technical Rescues in Failed Preservation, Session Room 6 (BMCC Level 3), October 9, 2026, 10:30 - 12:30 Purpose To identify pre-operative radiographic risk factors on pelvic imaging associated with symptomatic hip capsule failure following primary hip arthroscopy for femoroacetabular impingement (FAI). Methods A retrospective case–control study was conducted using a single surgeon’s database (September 2020 – June 2025). Cases were defined as patients with FAI who developed symptomatic post-operative capsular failure confirmed on magnetic resonance imaging. Each case was age- (± 5 years) and sex-matched to three controls without postoperative symptomatic capsular failure. Computed tomography and x-ray radiographic parameters of the hip and pelvis were recorded for each patient. Interrater reliability was assessed using intraclass correlation coefficients (ICCs). Variables meeting linearity and collinearity assumptions were entered into logistic regression models to identify independent predictors of capsular failure. Results Twenty-five cases (mean age 30.6 ± 9.9 years; 78% female) and 75 controls were analyzed. Excellent reliability was observed for alpha angle (ICC = 0.91), PWI (0.86), and modified neck–shaft angle (0.81). On univariate analysis, pre-operative acetabular anteversion at 1 o’clock (OR 1.08; 95% CI 1.01–1.14; p = 0.02), 2 o’clock (OR 1.07; 95% CI 1.00–1.14; p = 0.05), and increased AWI (OR 1.60 per 0.1 unit; 95% CI 1.20–2.15; p = 0.001) were significantly associated with capsule failure. In multivariable regression, mid-acetabular anteversion (2 o’clock; OR 1.08; 95% CI 1.00–1.17; p = 0.05) and AWI (OR 1.57 per 0.1 unit; 95% CI 1.19–2.08; p = 0.001) remained independently predictive of symptomatic failure. Conclusions Increased acetabular anteversion and anterior wall index on pre-operative imaging predicted symptomatic hip capsule failure after arthroscopy for FAI. Patients with these anatomical features may require alternative capsular management to mitigate postoperative capsule failure. Further research is required to validate this model and clarify its utility in preoperative assessment and planning.