Local Infiltration Analgesia Versus Regional Blockade for Postoperative Analgesia in Total Knee Arthroplasty: A Meta-analysis of Randomized Controlled Trials

Background: Total knee arthroplasty (TKA) is one of the most commonly performed procedureswhile postoperative analgesia still remains challenging. The efficacy and safety of local infiltrationanalgesia (LIA) versus regional blockade (RB; epidural analgesia and/or peripheral nerve block) forpain management after TKA are controversial.Objectives: The purpose of this meta-analysis was to determine whether LIA compared with RBwould provide better postoperative pain control, consume less morphine, facilitate early functionalrecovery, entail a differential risk of side effects and complications, and allow a shorter length ofstay.Study Design: This meta-analysis pooled all data published in randomized controlled trials (RCTs)examining the efficacy and safety of LIA versus RB following TKA.Setting: The work was performed at Affiliated Cixi Hospital, Wenzhou Medical University.Methods: Literature in English was searched using EMBASE, Medline, Cochrane Library, CINAHL,Web of Science, and Scopus from inception to April 2015. RCTs that compared LIA and RB forpostoperative analgesia following TKA were included. Methodological quality was assessed usingthe Cochrane Back Review Group checklist, and a sensitivity analysis was performed. Sixteen RCTswith a total of 1,206 patients were finally included in our study.Results: The results of our meta-analysis indicate that patients managed by LIA showedsignificantly lower numeric rating scale (NRS) score at rest (WMD: -0.40 [-0.72, -0.07]; P = 0.02)when compared with those managed by RB. Difference of morphine consumption was notsignificant (WMD: -1.39 [-7.21, 4.44]; P = 0.64) between the 2 groups. In terms of early functionalrecovery, the LIA group showed more straight leg raise (RR: 2.90 [2.15, 3.93]; P < 0.00001) onthe first postoperative day; better range of motion within one week (WMD: 4.33 [2.61, 6.05];P < 0.00001), but not at 3 months (WMD: 1.98 [-0.02, 3.98]; P = 0.05); and comparable kneesociety score (WMD: -8.79 [-27.05, 9.48]; P = 0.35). Length of hospital stay of the LIA group wasmarginally shorter (WMD: -0.25 [-0.49, -0.01]; P = 0.05) than that of the RB group. Risk of sideeffects and complications were comparable between groups.Limitations: The lack of a standard criterion regarding the technique details of LIA andheterogeneity resulting from the various analgesic components, dosages, and differentadministration methods might have posed a bias on the results.Conclusion: Our results have indicated that LIA provided better analgesia than RB at rest andpreserved quadriceps function in the immediate postoperative period, which may be beneficial toearly functional recovery. And its safety profile is reliable. With the biases in our meta-analysis, arigorous and adequately powered RCT is needed to validate our results.Key words: Local infiltration analgesia, regional block, peripheral nerve block, epidural analgesia,postoperative analgesia, total knee arthroplasty, meta-analysis, randomized controlled trial