Comparison of adductor canal block with local infiltration analgesia in primary total knee arthroplasty: A meta-analysis of randomized controlled trials.

Background: Currently, there remains a paucity of literature about the efficiency of adductor canal block (ACB) versus local infiltration analgesia (LIA) for pain management after total knee arthroplasty (TKA). The purpose of this study was to perform a relatively credible and overall assessment to compare the efficiency of ACB versus LIA for early postoperative pain treatment after TKA.

Methods: A comprehensive search of the published literature in PubMed, MEDLINE, Cochrane, EMBASE, and Web of Science databases was performed. Only randomized clinical trials (RCTs) or quasi-RCTs were included in this study. The primary outcome was pain score. Secondary outcome measures included opioid consumption, functional outcome (such as timed up and go test and distance walked), and length of stay.

Results: Eight RCTs with a total of 675 patients were included. No statistically significant difference was observed between the ACB and LIA groups in pain scores at 24 h or 48 h, total opioid consumption at 24 h or 48 h, and length of stay. However, the LIA group exhibited greater improvements in ambulation ability (P = 0.03) and distance walked (P < 0.00001).

Conclusions: Both treatments provide similar overall pain relief after TKA. LIA may achieve earlier ambulation compared with ACB. More high-quality RCTs are still required to make the final conclusion.