Effectiveness and weakness of local infiltration analgesia in total knee arthroplasty: a systematic review

Local infiltration analgesia has been widely used for pain relief in patients undergoing total knee arthroplasty. However, the effectiveness and major weakness of this technique have not been clarified; therefore, improvements in the technique have been limited. We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials and conducted a meta-analysis of randomized controlled trials comparing local infiltration analgesia with placebo infiltration in patients undergoing total knee arthroplasty. Fourteen trials involving 1305 knees were eligible. The results showed that local infiltration analgesia significantly reduced early perioperative pain and total narcotic consumption. However, postoperative functional outcomes were not significantly different between local infiltration analgesia and placebo. The pain-relieving effect of local infiltration analgesia was found to be strong but short in duration. In the future, modified delivery methods and formulas with longer durations of action and analgesia may provide a better environment for patients and therefore improve their function outcomes.