Abnormal Femoral Anteversion Is Associated With the Development of Hip Osteoarthritis: A Systematic Review and Meta-Analysis

PURPOSE: To perform a systematic review and meta-analysis of literature and to evaluate the relationship between abnormal femoral version and the development of hip osteoarthritis (OA). METHODS: A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, evaluating Level I and II studies. Included studies had to provide granular femoral version (FV) information. The severity of OA was ranked on the Kellgren–Lawrence (KL) scale. Excel version 1808 (Microsoft, Redmond, WA) was used to perform a student t test statistical analyses. RESULTS: Our review identified 19 qualifying studies—5 Level I and 14 Level II with 1,756 patients. Patients with FV above normal range (>14°) had greater KL scores than patients with normal range FV (mean ± standard deviation; 3.37 ± 1.44 vs 2.05 ± 1.72, P < .05). Analysis of KL scores in patients with FV >24° (>1 standard deviation) versus patients with FV >14° but <24° also demonstrated a positive correlation between increasing FV and KL (4.00 ± 1.96 vs 2.34 ± 0). This was significant independent of the presence or absence of developmental dysplasia of the hip. Retroverted hips (FV<10°) in the present study showed variable OA results upon analysis. CONCLUSIONS: The present review suggests that elevated FV may be a risk factor for more severe hip OA with or without the presence of concurrent dysplasia of the hip. The relative amount of increased anteversion appears positively correlated with severity of OA. Although femoral retroversion may impact hip mechanics, in this review it does not appear to strongly correlate with the development of OA. LEVEL OF EVIDENCE: II: systematic review of Level I and II studies.