Better clinical outcomes after unicompartmental knee arthroplasty when comparing with high tibial osteotomy

Background: Both high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) are well-established treatments for medial knee osteoarthritis (OA). However, it is unclear whether HTO or UKA leads to better clinical outcomes and lower complication rates. This meta-analysis compared the clinical outcomes and complications of HTO and UKA in patients with medial knee OA. Methods: All studies comparing the functional outcome, postoperative pain, revision rate to total knee arthroplasty (TKA), postoperative complications, postoperative velocity, and postoperative range of motion (ROM) as assessed with various measurement tools in patients with medial knee OA treated with HTO or UKA were included. Results: Sixteen studies were included in the meta-analysis. The proportion of patients who underwent revision to TKA (OR 1.56, 95% CI: 0.61-3.98; P=. 35) did not differ significantly between HTO and UKA. In contrast, functional outcome (OR 0.47, 95% CI: 0.24 to 0.95; P=. 04), postoperative pain (OR 0.28, 95% CI: 0.12 to 0.62; P=. 002), postoperative complications (OR 2.48, 95% CI: 1.26 to 4.90; P=. 009), postoperative velocity (95% CI: -0.11 to -0.00; P=. 03), and postoperative ROM (95% CI: 2.02 to 15.23; P=. 01) were significantly different between the 2 groups. Conclusions: There were no significant differences in the revision rate to TKA between HTO and UKA. However, results from subgroup analyses suggested that opening-wedge HTO resulted in a lower revision rate to TKA than did UKA, whereas closing-wedge HTO resulted in a higher revision rate to TKA than did UKA. In addition, UKA resulted in significantly better functional outcomes and postoperative velocity, along with less postoperative pain, fewer postoperative complications, and lower postoperative ROM. Based on the findings of current meta-analysis, UKA appears to be as efficacious and safe as HTO in the treatment of medial knee OA.