Comparative outcomes of revision total knee arthroplasty: a systematic review and meta-Analysis of high tibial osteotomy vs. unicompartmental knee arthroplasty.

Purpose: High tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) are two common approaches for managing unicompartmental knee osteoarthritis. However, both procedures may eventually require revision to total knee arthroplasty (TKA). This study aims to compare the clinical outcomes and functional performance of revision TKA following HTO (HTO-TKA) versus revision TKA following UKA (UKA-TKA). The findings are intended to offer valuable insights for optimizing treatment strategies for patients with knee osteoarthritis in clinical practice.

Methods: The postoperative clinical outcomes and functional results of HTO-TKA and UKA-TKA were assessed through a comprehensive review of relevant literature from PubMed, Embase, the Cochrane Library, and Web of Science up to October 2024. Primary endpoints included knee function scores, postoperative complications, and revision rates. Secondary endpoints encompassed operation time, range of motion (ROM), postoperative infections, and the types of revision implants used.

Results: This meta-analysis included 11 retrospective studies involving a total of 10,045 patients. The results demonstrated that the HTO-TKA group had significantly better knee function scores compared to the UKA-TKA group (MD = 3.35, 95% CI: [0.84, 5.87], I²=95%, P = 0.009). Although the HTO-TKA group showed statistically higher knee function scores, the mean difference (MD = 3.35) did not reach the established MCID threshold for KSS (6-10 points), indicating that the clinical significance of this difference remains uncertain. Additionally, fewer revision implants were required in the HTO-TKA group (OR = 0.11, 95%CI: [0.05, 0.23], I²=90%, P < 0.00001). However, no statistically significant differences were observed between the two groups in terms of postoperative complications (OR = 1.21, 95% CI: [0.67, 2.17], I²=59%, P = 0.53), revision rates (OR = 0.81, 95% CI: [0.53, 1.26], I²=76%, P = 0.35), operation time (MD=-2.00, 95%CI: [-11.22, 7.21], I²=91%, P = 0.67), range of motion (ROM) (MD=-0.04, 95% CI: [-3.69, 3.61], I²=0%, P = 0.98), or postoperative infections (OR = 0.81, 95% CI: [0.56, 1.17], I²=48%, P = 0.26). Sensitivity analysis indicated heterogeneity, prompting the need for a subgroup analysis. After manual removal, the HTO-TKA group had a lower revision rate compared to the UKA-TKA group (OR = 0.65, 95% CI: [0.51, 0.83], I²=18%, P = 0.0006), and the HTO-TKA group had a statistically significant shorter operative time compared to the UKA-TKA group (MD=-9.15, 95% CI: [-11.97, -6.33], I²=33%, P < 0.00001).

Conclusion: While HTO-TKA was associated with marginally better knee function scores and reduced revision implant usage compared to UKA-TKA, the clinical relevance of these differences remains uncertain. Clinicians should weigh these findings against the limitations of retrospective data and evolving surgical techniques when selecting between HTO and UKA for patients with medial compartment KOA.

Clinical Trial Number: Not applicable.