From the *Department of Anaesthesia and Intensive Care Medicine, Copenhagen University Hospital, Gentofte Hospital, Gentofte; †Section of Acute Pain Management, Department of Anaesthesia, Centre of Head and Orthopaedics, Copenhagen University Hospital, Rigshospitalet, Copenhagen; and ‡Department of Orthopaedic Surgery, Copenhagen University Hospital, Gentofte Hospital, Gentofte; and §Department of Anaesthesia, Centre of Head and Orthopaedics, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
Reg Anesth Pain Med. 2015 Jan-Feb;40(1):3-10. doi: 10.1097/AAP.0000000000000169.
Total knee arthroplasty (TKA) is often associated with severe pain. Different regional anesthetic techniques exist, all with varying degrees of motor blockade. We hypothesized that pain relief provided by the adductor canal block (ACB) could increase functional muscle strength.
We included 50 TKA patients with severe movement-related pain; defined as having visual analog scale pain score of greater than 60 mm during active flexion of the knee. The ACB group received an ACB with ropivacaine 0.2% 30 mL and a femoral nerve block (FNB) with 30 mL saline. The FNB group received an ACB with 30 mL saline and an FNB with ropivacaine 0.2% 30 mL. We compared the effect of the ACB versus FNB on maximum voluntary isometric contraction of the quadriceps muscle relative to a postoperative baseline value. Secondary end points were differences between groups in ability to ambulate and changes in pain scores (Clinicaltrials.gov identifier NCT01922596).
After block, the quadriceps maximum voluntary isometric contraction increased to 193% (95% confidence interval [CI], 143-288) of the baseline value in the ACB group and decreased to 16% (95% CI, 3-33) in the FNB group with an estimated difference of 178% (95% CI, 136-226), P < 0.0001. Pain scores were similar between groups. Before block, 2 of 25 patients in each group were unable to perform the Timed-Up-and-Go test; after block, this number increased to 7 of 25 in the FNB group and decreased to 0 of 25 in the ACB group.
Adductor canal block provides a clinically relevant and statistically significant increase in quadriceps muscle strength for patients in severe pain after TKA.
全膝关节置换术（TKA）常伴有剧烈疼痛。存在不同的区域麻醉技术，均具有不同程度的运动阻滞。我们假设，股神经内收肌管阻滞（ACB）提供的疼痛缓解可以增加功能性肌肉力量。
我们纳入了 50 例 TKA 术后伴有严重运动相关疼痛的患者；定义为膝关节主动屈曲时视觉模拟评分（VAS）疼痛评分大于 60mm。ACB 组接受 0.2%罗哌卡因 30mL 的 ACB 和 30mL 生理盐水的股神经阻滞（FNB）。FNB 组接受 30mL 生理盐水的 ACB 和 30mL 0.2%罗哌卡因的 FNB。我们比较了 ACB 与 FNB 对术后基线值的股四头肌最大等长收缩的影响。次要终点是两组在行走能力和疼痛评分变化方面的差异（Clinicaltrials.gov 标识符 NCT01922596）。
阻滞后，ACB 组股四头肌最大等长收缩增加至基线值的 193%（95%置信区间[CI]，143-288），FNB 组下降至 16%（95%CI，3-33），估计差异为 178%（95%CI，136-226），P<0.0001。两组疼痛评分相似。阻滞前，每组各有 2 例患者无法进行计时起立行走测试；阻滞后，FNB 组增加至 25 例中的 7 例，ACB 组减少至 25 例中的 0 例。
股神经内收肌管阻滞可显著增加 TKA 术后剧烈疼痛患者的股四头肌力量，具有临床意义。
