Hip‐Combined Rotational Morphology Has Little Short‐Term Impact on Clinical Outcomes Following Hip Arthroscopy in Patients With Femoroacetabular Impingement Syndrome

PURPOSE: To examine the association between hip-combined rotational morphology and clinical outcomes following primary hip arthroscopy. METHODS: Patients who underwent primary hip arthroscopy at our institute from January 2021 to July 2022 with a clear diagnosis of femoroacetabular impingement syndrome (FAIS) and had a minimum 2-year follow-up were included. Computed tomography scans on the surgical hip and ipsilateral distal femur were routinely performed for all participants. Femoral version (FV) and acetabular version (AV) were assessed using axial computed tomography images. The combined rotational morphology was defined as the combination of FV and AV. Preoperative and minimum 2-year postoperative patient-reported outcome scores including visual analog scale, modified Harris Hip Score (mHHS), and the 12-item International Hip Outcome Tool were compared among FAIS patients with normal, increased, and decreased FV-AV combinations. The percentage of patients achieving the minimal clinically important difference (MCID) and patient-acceptable symptom state for the mHHS and 12-item International Hip Outcome Tool was also recorded and compared across the different FV-AV combination groups. RESULTS: A total of 205 eligible FAIS patients were analyzed, who were further categorized into normal FV-AV combinations (n = 98), increased FV-AV combinations (n = 62), and decreased FV-AV combinations (n = 45). Statistically significant improvements were found in all patient-reported outcome scores involved when comparing the follow-up results with the preoperative baseline scores (all P < .001). No statistically significant differences were observed in the preoperative and postoperative patient-reported outcome scores among patients with normal, increased, and decreased FV-AV combinations (all P > .05). The percentage of patients achieving the MCID for mHHS was significantly lower in patients with decreased FV-AV combinations (P = .041). Although patients with high baseline scores (preoperative mHHS > 90 points) were excluded to control the potential ceiling effect, multivariate regression analysis still found that the decreased FV-AV combination was significantly associated with the failure of patients achieving MCID for mHHS, with an odds ratio of 6.38 (95% confidence interval = 1.30-31.36; P = .023). No significant differences were found in the percentage of patients achieving patient-acceptable symptom state for mHHS (P = .383) or 12-item International Hip Outcome Tool (P = .619). CONCLUSIONS: Hip-combined rotational morphology has little short-term impact on clinical outcomes after hip arthroscopy in FAIS patients. Patients with decreased combined version are less likely to achieve MCID for mHHS at a follow-up period of at least 2 years. LEVEL OF EVIDENCE: Level IV, retrospective case series.