Assessment of the duration and effectiveness of intra-articular lidocaine injections for groin pain in patients with labral tears involving early osteoarthritis

Introduction: Intra-articular lidocaine injections have been used to confirm the hip pathology and may predict the efficacy of arthroscopic surgery. We have routinely performed the injections as a surgical indicator. The aim of this study was to assess the duration and effectiveness of these diagnostic intra-articular lidocaine injections on groin pain in patients with labral tears involving early osteoarthritis. Methods: A total of 113 patients were included in this study. All patients received one injection of 10 ml of 1% lidocaine into the hip joint under fluoroscopy. The duration and effectiveness of the injection were assessed 2 weeks after the injection and at a minimum of 1 year of follow-up. The effect of the injection was graded as 0: unchanged or worse; 1: an effect only on the day of injection; 2: the effect lasted a few days; 3: the effect lasted about a week; and 4: symptom remission. In addition, we recorded whether hip arthroscopic surgery was eventually performed. Results: The effect was rated as 0 in 19 patients (16.8%), as 1 in 30 patients (26.5%), as 2 in 38 patients (33.6%), as 3 in 13 patients (11.5%), and as 4 in 13 patients (11.5%). Seventy-two patients (63.7%) underwent hip arthroscopic surgery. No relationship with patients’ characteristics was found. Conclusion: In total, 83% of patients experienced some effect of the lidocaine injection. Furthermore, 11.5% of patients experienced complete remission of their symptoms.