The study compared the efficacy of liposomal bupivacaine (133 mg, group L) and ropivacaine (50 mg, group R) for sciatic and saphenous nerve blocks in 142 patients undergoing elective foot and ankle surgery. It was a single-center, double-blind, randomized controlled trial registered under ChiCTR2400088305 with ethical approval. The primary outcome was postoperative sufentanil consumption, secondary outcomes included duration of analgesia, motor blockade, quality of recovery, sleep, and adverse events. Group L had significantly lower sufentanil consumption at 12, 24, 48 and 72 hours after surgery (all p < 0.001). This group also showed higher quality of sleep and recovery on postoperative day 1 (p < 0.001). Multivariable analysis identified surgical type, preoperative sleep quality, and Pain Catastrophizing Scale score as independent predictors of postoperative pain trajectory. Liposomal bupivacaine reduces opioid consumption and prolongs nerve block without changes in adverse events.