Background: Uni-knee arthroplasty (UKA) has shown better knee kinematics and motion that may better suit the activities of daily living in Eastern countries. The purpose of this study was to evaluate the functional outcomes of UKA for medial compartment knee arthropathy in Asian patients.
Methods: The study cohort consisted of 48 patients with 51 UK A knees. Only one type of prosthesis was used and all components were cemented. Postoperative management included ambulation with weight bearing, range of motion, and muscle strengthening exercises as tolerated until full recovery. The average follow-up was 52.0 ± 24.0 (range 12-92) months. The evaluation included functional assessment, the Knee Society knee and functional scores, the International Knee Document Committee (IKDC) subjective and objective scores, and radiographs of the knee.
Results: The overall clinical outcomes of the knee showed the functional outcome of the knee to be normal in 51%, nearly normal in 37%, abnormal in 8%, and severely abnormal in 4%. The functional activities included stair climbing in 96%, squatting in 76%, jogging in 71% and kneeling in 47%. Three-quarters of the patients were able to kneel for daily activities. Approximately 98% of the patients were satisfied with the operation. The survivorship of the prosthesis was 98% with one revision pending. Radiographic evaluations revealed the components were centered in 82% and off-centered in 18%. Osteoarthritis was 22% preoperative and 27% postoperative for the patellofemoral compartment, and 0% before and 4% after surgery for the lateral compartment. The functional outcomes showed no difference between patients with and without patellofemoral arthritis. The complications included one component malposition and one knee pain of undetermined origin.
Conclusions: UKA provides excellent pain relief and restoration of knee function including kneeling, squatting, and sit-to-stand activities that perfectly fit the oriental lifestyle and high patient satisfaction in Asian patients at medium-term follow-up. The complications were rare and the survival rate was 98% at medium-term follow-up.