Background: Sciatic nerve block (SNB) is widely used as a supplemental analgesia after total knee arthroplasty (TKA) combined with femoral nerve block (FNB). Despite its effectiveness, SNB often causes peroneal nerve paralysis, which makes it difficult to detect peroneal nerve injury by surgical process. Recently, periarticular infiltration analgesia (PIA) is reported that it provides analgesia without peroneal nerve paralysis. We conducted a retrospective analysis to compare the effectiveness of SNB and PIA.
Methods: This study was approved by the local institutional ethics committee; 17 patients undergoing TKA under general anesthesia with continuous femoral nerve block were enrolled in the study. All patients received continuous FNB. Nine patients received sciatic nerve block successively, while 8 patients received PIA around the time of insertion of artificial joint. Primary outcome measure was the frequency of peroneal nerve paralysis when the patients woke up. Secondary outcome measures included numerical rating scale (NRS) until postoperative day 3.
Results: While there were 6 patients who had peroneal nerve paralysis in the SNB group, none of them had it in the PIA group (P = 0.009). There were no significant differences of the NRSs between the two groups.
Conclusions: PIA provided sufficient analgesia after TKA without peroneal nerve paralysis.