Seventeen randomized trials were included in this meta-analysis comparing the addition of acetaminophen or placebo to a multi-modal pain management protocol in patients undergoing total joint arthroplasty (hip or knee). Pooled outcomes of interest included post-operative pain, difference in sum of pain intensity, post-operative opioid consumption, and the risk of complications. Meta-analysis results demonstrated that intravenous acetaminophen resulted in statistically significantly lower opioid consumption at 24 hours (p<0.05), and statistically favourable differences in pain intensity at 6 hours (p<0.05), compared to placebo. Pooled post-operative pain scores were statistically significantly in favour of the intravenous/oral acetaminophen group compared to the placebo group (p<0.05). No statistically significant differences in the pooled risk of post-operative complications were observed between the two groups (p>0.05).