Four randomized controlled trials were included in this meta-analysis which investigated the comparative efficacy of intrathecal morphine and a femoral nerve block for postoperative analgesia following total knee arthroplasty. Pooled outcomes included pain scores, postoperative morphine consumption, and treatment-related adverse events, such as postoperative nausea and vomiting, as well as itching. The results on analgesic outcomes demonstrated no significant differences between methods at 6, 12, or 24 hours after surgery. The incidence of postoperative nausea and vomiting also did not significantly differ between groups. The incidence of postoperative itching was significantly higher following treatment with intrathecal morphine compared to the femoral nerve block group.