Liposomal bupivacaine for popliteal sciatic and saphenous nerve blocks in patients undergoing foot and ankle surgery: a single-center, double-blind, randomized controlled trial

Background Patients undergoing foot and ankle surgery often experience severe postoperative pain. This study aimed to assess the efficacy of liposomal bupivacaine for popliteal sciatic and saphenous nerve blocks in managing pain after foot and ankle surgery. Methods The study was registered with the Chinese Clinical Trial Registry (ChiCTR2400088305) and received ethical approval from the Institutional Review Board of Xuzhou Renci Hospital (XZRCLL-KT-202407003). In this randomized trial, 142 patients undergoing elective foot/ankle surgery received popliteal-sciatic and saphenous nerve blocks with either 50 mg ropivacaine (R group) or 133 mg liposomal bupivacaine (L group). Primary outcome was postoperative sufentanil consumption; secondary outcomes included analgesia duration, motor blockade, recovery quality, sleep quality, and adverse events. Results Compared with Group R, Group L demonstrated significantly lower sufentanil consumption at 12 h, 24 h, 48 h, and 72 h postoperatively (all p < 0.001). The L group exhibited significantly higher sleep quality ( p < 0.001) and quality of recovery ( p < 0.001) on postoperative day 1. Multivariable logistic regression analysis identified surgical type, preoperative sleep quality, and Pain Catastrophizing Scale scores as independent predictors of postoperative pain trajectory. Conclusion The administration of liposomal bupivacaine for popliteal sciatic and saphenous nerve blocks significantly reduces postoperative opioid consumption and extends nerve block duration, providing a safe and effective technique for postoperative analgesia in patients undergoing foot and ankle surgery. Preoperative sleep quality, surgical type, and Pain Catastrophizing Scale score are independent predictors of the pain trajectory that can identify patients more likely to benefit from liposomal bupivacaine. Clinical trial registration https://www.chictr.org.cn , Identifier ChiCTR2400088305.