Study on the Analgesic Efficacy of Femoral Nerve Block for Post-Hip Arthroscopy Pain

Postoperative pain management is challenging for hip arthroscopy, and the effectiveness and specific protocols of femoral nerve block (FNB) in hip surgeries remain insufficient. Therefore, we designed this study to investigate the analgesic efficacy and optimal drug concentrations of FNB after hip arthroscopy. A total of 148 patients undergoing hip arthroscopy were included and randomly divided into three groups: 0.3% ropivacaine FNB group, 0.4% ropivacaine FNB group, and 0.4% ropivacaine intra-articular injection (IAI) group (positive control). The main outcomes included dynamic and static visual analog scale (VAS) scores at various time points postoperatively, total intraoperative remifentanil consumption, and cumulative consumption of morphine within 24 h postoperatively. Secondary outcomes included total intraoperative dexmedetomidine consumption, RASMAY sedation scores, and patients' satisfaction scores postoperatively. Both FNB and IAI anesthesia were shown to be safe for post-hip arthroscopy analgesia. Compared with IAI anesthesia, FNB showed no significant differences in analgesic effect within 12 h postoperatively but had a better analgesic effect after 24 h and lower remifentanil consumption intraoperatively. Group 0.4% ropivacaine showed lower dynamic VAS scores within the first 12 h compared with 0.3% ropivacaine for FNB, however, there were no significant differences in patient satisfaction and sedation, and postoperative ambulation was delayed, indicating that the higher concentration of ropivacaine correlated with a longer time to ambulation. The IAI group had greater intraoperative opioid consumption and more side effects. Compared with IAI anesthesia, FNB can better alleviate post-hip arthroscopy pain and reduce opioid consumption. However, it requires specialized equipment and technical support and carries a certain risk of puncture. Chinese Clinical Trials Registry (ChiCTR2400091579).