Epidemiological Characteristics and Factors Affecting Baseline Hip Function in Chinese Patients Undergoing Arthroscopic Treatment for Femoroacetabular Impingement Syndrome.

Background: Femoroacetabular impingement syndrome (FAIS) is one of the most common causes of hip pain. However, the epidemiology of FAIS in the Chinese population remains unknown. Purpose: To investigate the epidemiological characteristics, arthroscopic findings, and baseline hip function of Chinese patients undergoing arthroscopic treatment for FAIS and to identify potential factors influencing baseline hip function. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Data between August 2016 and September 2022 were reviewed at a single institution. Patients who were diagnosed with FAIS and underwent hip arthroscopic surgery were included. Exclusion criteria were as follows: Tönnis grade >1, previous surgery of the lower limbs and spine, and concomitant hip conditions. Baseline characteristics including sex, age at surgery, affected side, body mass index, duration of symptoms, and previous surgery were collected. Radiographic measurements including alpha angle, lateral center-edge angle, and Tönnis grade were obtained. Intra-articular lesions and arthroscopic procedures were recorded. Preoperative patient-reported outcome scores including those for the modified Harris Hip Score (mHHS) and visual analog scale for pain were collected. Univariate and multivariate linear regression analyses were performed to determine the factors affecting baseline hip function. Results: A total of 1206 patients were included in the study. Among them, 50.5% were female, and 49.5% were male. The mean age was 37.4 years. Male patients had a larger alpha angle (65.8° vs 61.1°, respectively) and a higher prevalence of cam-type deformities compared with female patients (all Conclusion: The cohort of Chinese patients undergoing arthroscopic treatment for FAIS primarily comprised young and middle-aged adults, with a balanced sex distribution. Male patients had a larger alpha angle, higher prevalence of cam-type deformities, and higher proportion of cartilage lesions in the femoral head and acetabulum compared with female patients. Older age and female sex were associated with inferior baseline hip function.