Data from 18 RCTs, with 1858 patients who underwent total knee arthroplasty, were pooled to investigate the efficacy of local infiltration analgesia (LIA) against controls. Pooled analyses of VAS pain at 2, 4, 6, 12, 24, and 48 hours were conducted, along with morphine consumption, functional recovery, length of stay, and adverse events. The evidence presented in this meta-analysis demonstrated that LIA was associated with lower VAS pain at 2, 4, 6, 12, 24, and 48 hours, less morphine consumption, and improved functional recovery. Length of stay was unaffected by intervention, and adverse events were comparable between groups.