Related Experiment Video
Updated: May 22, 2026
In Vitro Application of a Wireless Sensor in Flexion-Extension Gap Balance of Unicompartmental Knee Arthroplasty
Published on: May 5, 2023
Greater knee flexion and patient-reported function after unicompartmental knee arthroplasty than after total knee
Kohei Nishitani1, Shinichi Kuriyama2, Yugo Morita2
1Department of Orthopaedic Surgery, Kyoto University, Kyoto, Japan. nkohei@kuhp.kyoto-u.ac.jp.
Purpose:
The purpose of this study was to compare knee range of motion and 2011 Knee Society Score (2011KSS) after unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) in background-matched cohort.
Methods:
UKA and TKA for medial knee osteoarthritis were included, and preoperative patient backgrounds, knee alignment, osteoarthritis severity, knee range of motion, 2011KSS symptoms, satisfaction and functional activities were matched using a propensity score. Knee range of motion and 2011KSS were evaluated two year postoperatively.
Results:
Among 116 UKAs and 656 TKAs, 98 each arthroplasty were matched (mean 75 years). UKA showed greater knee flexion (mean: 136.6° vs 122.4°, p < 0.001) and 2011KSS functional activities (median: 78 vs 68, p = 0.04) at 2-year. There were no differences in knee extension or other 2011KSS domains.
Conclusion:
UKA showed greater knee flexion and subjective functional score than TKA. UKA may be beneficial for populations with high flexion demands.