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Updated: Oct 25, 2025

In Vitro Application of a Wireless Sensor in Flexion-Extension Gap Balance of Unicompartmental Knee Arthroplasty
Published on: May 5, 2023
Unicompartmental vs. total knee replacement in patients with failed high tibial osteotomy
Andrea Parente1, Claudio Legnani2, Marco Bargagliotti3
1IRCCS Istituto Ortopedico Galeazzi, Hip and Knee Arthroplasty Surgery Center, Milan, Italy.
Introduction:
The influence of a previous high tibial osteotomy (HTO) on the outcome and survival of a knee arthroplasty is a debated issue. The purpose of this study is to compare subjective, radiographic, and functional outcomes of unicompartmental knee replacement (UKR) and total knee replacement (TKR) after failed open wedge HTO.
Methods:
26 post-HTO UKRs (group A) with an average follow-up of 7.8 years (range 2-13), and 33 post-HTO TKRs (group B) with an average follow-up of 11.2 years (range 4-16) operated between 2001 and 2017, were retrospectively reviewed. Assessment included Knee Society Score (KSS), University of California at Los Angeles Activity Score (UCLA), and Western Ontario and McMaster University Osteoarthritis Index (WOMAC). Standard knee X-rays, and long-standing X-rays were performed pre-operatively and at follow-up to evaluate prosthesis survival, coronal alignment, and patellar height.
Results:
Improvements regarding KSS, UCLA and WOMAC scores were noted at follow-up in both groups compared to pre-operatory status (p < 0.001). No statistically significant differences in clinical and functional postoperative scores were reported between groups (p = n.s.) at follow-up. Group B presented a more neutral mean mechanical axis of 0.5° compared to 2.7° in Group A (p < 0.001).
Conclusions:
Performing UKR after previous failed HTO is a safe and effective procedure which leads to clinical, radiological and functional outcomes comparable to TKR after HTO.
