Medial unicompartmental replacement for tricompartmental disease in the elderly

Between 1993 and 1998, we performed 18 unicompartmental arthroplasties of the knee, all on the medial side, in a selected group consisting of 18 elderly patients aged 74-81 (mean 77.2), with severe arthrosis mainly in the medial compartment and mild arthrosis in the lateral compartment and the patellar articular surface mostly covered with articular cartilage. The patients were mainly housebound due to relatively advanced age and severe pain. Unicompartmental arthroplasty was chosen for this group because of a quicker and easier rehabilitation. Two patients had had a high tibial osteotomy 7 and 10 years ago. The average follow up was 5.5 years ranging in age from 5 to 8 years. The average initial American Knee Society Knee Score was 52, ranging from 28 to 70 which improved at follow up to 83 (range 60-92). All prostheses used were Allegretto (Sulzer). The operation was done through short medial arthrotomy. The purpose of this study is to report our results in these low demand patients and although the follow-up was only 5-8 years, the results are promising.