【Abstract】Objective To compare the effect of ultrasoundguided popliteal sciatic nerve block and popliteal sciatic nerve combined with saphenous nerve block in post operative analgesia following tibiofibular fracture with double incision. Methods 90 patients undergoing tibiofibular fractures surgery underwent doubleincision internal fixation were randomly divided into sciatic nerve block group (group A), combined block group (group B) and control group (group C) with 30 cases each group. Group A and group B were treated with 033% ropivacaine before spinal anesthesia with ultrasoundguided popliteal sciatic nerve block and sciatic nerve + saphenous nerve block respectively. 20 minutes after the nerve block was effective, spinal anesthesia was performed with 3 ml of a specific gravity liquid such as 05% bupivacaine. When the patient's VAS score was ≥ 4 points, a specific person was responsible for opening the patientcontrolled intravenous analgesia pump (referred to as PCIA pump) as a remedy for poor analgesic effect. The PCIA pump consists of morphine 2 mg/kg plus saline to 100 ml. Rest and movement visual analogue score (VAS), Ramsay, BCS and muscle strength grading were observed at 1h, 3h, 6h and 12h after operation. The time of PCIA opening, the number of effective PCIA compressions within 12h after operation, the patients' satisfaction with analgesic treatment and adverse reactions after 12h were observed.Results The time of sensorimotor block in group B and group A was higher than that in group C (P＜005), and group B was greater than group A (P＜005). There was no statistically significant difference in the time of motor block between the group B and group A. PCIA pumpassisted analgesia was used in group C at the earliest, followed by group A, and was used in group B at the latest (morphine consumption was the least), with statistically significant differences among the three groups (P＜005). Within 12 hours after operation, the rest and movement VAS score, BCS score and PCIA effective compression times were significantly better in group A and group B than in group C (P＜005), and group B was better than group A (P＜001). There was a difference in the satisfaction rate of analgesia treatment between different postoperative analgesia methods (P＜005). The analgesic satisfaction of patients in group B was the highest, and group A was better than group C. The incidence of nausea and vomiting was the highest in group C, followed by group A and group B. There were statistically significant differences between the three groups (P＜005). Conclusion Application of popliteal sciatic nerve block guided by ultrasound combined saphenous nerve block in tibiofibular fracture and double incision surgery can improve the effect of postoperative analgesia, reduce the dosage of postoperative opioids, reduce postoperative nausea and vomiting, also has higher patient satisfaction.