Long-term survival is similar between closed-wedge high tibial osteotomy and unicompartmental knee arthroplasty in patients with similar demographics

Abstract

PurposeLong-term clinical and radiographic results and survival rates were compared between closed-wedge high tibial osteotomy (HTOs) and fixed-bearing unicompartmental knee arthroplasty (UKA) in patients with similar demographics.MethodsSixty HTOs and 50 UKAs completed between 1992 and 1998 were retrospectively reviewed. There were no significant differences in pre-operative demographics. The mean follow-up period was 10.7\u2009±\u20095.7\xa0years for HTO and 12.0\u2009±\u20097.1\xa0years for UKA (n.s.). The Knee Society knee and function scores, WOMAC, and range of motion (ROM) were investigated. The mechanical axis and femorotibial angle were evaluated. Kaplan–Meier survival analysis was performed (failure: revision to TKA) and the failure modes were investigated.ResultsMost of the clinical and radiographic results were not different at the last follow-up, except ROM; ROM was 135.3°\u2009±\u200912.3° in HTO and 126.8°\u2009±\u200913.3° in UKA (p\u2009=\u20090.005). The 5-, 10-, 15-, and 20-year survival rates were 100%, 91.0%, 63.4%, and 48.3% for closed-wedge HTO, respectively, and 90.5%, 87.1%, 70.8%, and 66.4% for UKA (n.s.). The survival rate was higher than that for UKA until 12\xa0years post-operatively but was higher in UKAs thereafter, following a remarkable decrease in HTO. The most common failure mode was degenerative osteoarthritic progression of medial compartment in HTO and femoral component loosening in UKA.ConclusionsLong-term survival did not differ significantly between closed-wedge HTO and fixed-bearing UKA in patients with similar pre-operative demographics and knee conditions. The difference in post-operative ROM and failure mode should be considered when selecting a procedure.Level of evidenceIII.