目的　评价超声引导下股神经阻滞应用于膝关节镜的术后镇痛作用。 方法　60例择期膝关节镜手术患者，随机分为对照组（A组）和试验组（B组），每组30例。两组患者均在椎管内麻醉下完成手术，B组术毕在超声引导下行股神经阻滞，A组不予任何处理。记录术后6、12、24 h患者静息与活动时VAS疼痛评分及24h内镇痛药补充给予人次、不良反应发生率、患者满意度评分。 结果　A组患者术后6、12、24 h VAS评分及24 h内镇痛药补充给予人次明显大于B组（P＜0.05）；其不良反应发生率高于B组但无统计学意义；A组患者满意度评分明显低于B组（P＜0.05）。 结论　超声引导下股神经阻滞应用于膝关节镜手术，术后镇痛效果确切，不良反应少，患者舒适满意，是一种安全有效的镇痛方式。

Objective　To research the effect of postoperative analgesia with ultrasound guided femoral nerve block used in arthroscopically-assisted knee operation.  Method　Sixty patients undergoing arthroscopically-assisted knee operation were divided equally and randomly into two groups: normal group (A, n=30) and research group(B, n=30). All of the patients were anesthetized with spinal anesthesia. Patients in group B received ultrasound-guided femoral nerve block, which patients in group A received no further management. the analgesic effect(VAS) 6h、12h、24h postoperatively and analgesia drugs consumption, incidence of side effects, degree of comfort in 24 hours postoperatively in all patients were observed.  Results  Compared with group A，analgesic effect was significant better with less extra drugs consumption and more comfort in group B. Group B had incidence of complications but no statistical difference could be detected.  Conclusion　Ultrasound guided femoral nerve block used in arthroscopically-assisted knee operation can bring better postoperative analgesia and reduce the adverse effects. It can make patients  feel comfortable.