Twenty-one studies including 1145 patients undergoing total hip or knee arthroplasty were included in this meta-analysis comparing peri-operative ketamine and control for the management of post-operative pain and reduction of opioid consumption. Pooled outcomes of interest included pain on a Visual Analog Scale (VAS), opioid consumption in morphine equivalents, and the incidence of side effects (i.e., sedation, dizziness, hallucination; post-operative nausea and vomiting, sweating, pruritus, urinary retention, constipation, version trouble, nightmare, and delirium). Pooled results revealed statistically significantly lower VAS pain scores at 6 hours, 12 hours, 24 hours and 48 hours post-operation in the ketamine group compared to the control group (p<0.01 for all). Pooled opioid consumption in morphine equivalents were statistically significantly lower in the ketamine group at 24 hours (p=0.003), and 48 hours (p=0.003) post-operation. The pooled incidence of post-operative nausea and vomiting was statistically significantly lower in the ketamine group (p=0.0008); otherwise, no statistically significant differences were observed in the pooled incidence of side effects between the two groups.