Five studies (542 patients) were included in this meta-analysis comparing primary total knee arthroplasty with and without synovectomy for the treatment of knee osteoarthritis. Outcomes of interest included post-operative pain, clinical and functional knee society scores (KSS), range of motion, drainage, difference in pre-operative and post-operative hemoglobin levels, transfusion rate, and complications. The pooled results revealed significantly higher drainage and and change in hemoglobin levels in the synovectomy group compared to the synovium retention group. No significant differences in the remaining outcomes were observed between the synovectomy and synovium retention groups.