Abstract
Purpose
Unicompartmental Knee Arthroplasty (UKA) has been indicated for inactive elderly patients over 60, but for young and active patients less than 60 years old, it has been regarded as a contraindication. The purpose of this study is to evaluate the usefulness of UKA performed on young Asian patients under 60 years of age by analyzing clinical outcomes, complications and survival rate.
Materials and Methods
The subjects were 82 cases, which were followed up for at least 5 years (from 5 to 12 years). Only Oxford phase III® (Biomet Orthopedics, Inc, Warsaw, USA) prosthesis was used for all cases. The clinical evaluation was done by the range of motion, Knee society score (KSS), WOMAC score. The radiographic evaluation was performed on weight bearing long-leg radiographs, AP and lateral view of the knee and skyline view of the patella. The survival rate was estimated by Kaplan-Meier survival analysis.
Results
Three bearing dislocations, one medial tibial collapse and one lateral osteoarthritis occurred, so the complication rate was 6.1% (5/82). Among the 3 cases of bearing dislocation, 2 cases were resolved by replacing with a thicker bearing and 1 case was converted to TKA due to repeated dislocation. One case of medial tibia collapse and one lateral osteoarthritis were converted to total knee arthroplasty (TKA). All clinical outcomes measured by KSS scores and WOMAC score showed a statistically significant difference (p<0.001). The 10 year cumulative survival rate using Kaplan-Meier survival method was 94.7% (95% CI: 88.7%–100%).
Conclusion
The clinical outcomes and the survival rate of young asian patients less than 60 years of age who underwent Oxford medial UKA showed good clinical results and a good survival rate in the mid-term results. However, long-term follow-up is needed for more reliable clinical results.
