Utility of Ultrasound‐Guided Anesthetic Intra‐articular Injection to Estimate the Outcome of Hip Arthroscopy in Patients with Femoroacetabular Impingement Syndrome

Objective To investigate the effectiveness of ultrasound (US) guided intra‐hip joint injection to estimate the outcome of hip arthroscopy in patients with femoroacetabular impingement (FAI) syndrome. Methods Patients with FAI syndrome (n = 60) were prospectively enrolled in our study. Before hip arthroscopy, a mix of 4 mL 2% lidocaine and 4 mL 1% ropivacaine were injected into the hip joint under the guidance of US. The clinical efficacy of the intra‐articular injection was evaluated by comparing the visual analog scale (VAS) and international hip outcome tool 12 (iHOT‐12) results before and after the injection. The outcome of hip arthroscopy was evaluated by iHOT‐12, the modified Harris hip score (MHHS), and the patient's satisfaction 12 months after the operation. The outcome of intra‐articular injection and hip arthroscopy were compared. Factors related to the outcomes of hip arthroscopy were evaluated. The correlation between the efficacy of intra‐hip joint injection and arthroscopy was evaluated. Results The VAS of patients decreased from 11.3 ± 7.7 to 3.3 ± 4.5, and the iHOT‐12 increased from 52.1 ± 23.2 to 84.1 ± 18.1 after intra‐articular injection (all P