Treatment of Spontaneous Osteonecrosis of the Knee Using the Oxford Unicompartmental Knee Arthroplasty

Abstract

Purpose: The purpose of this study was to evaluate the clinical and radiographic outcomes of unicompartmental knee arthroplasty (UKA) in patients with spontaneous osteonecrosis. Materials and Methods: Between September 2002 and March 2005, 15 patients with 16 knees were treated with UKA for the treatment of spontaneous osteonecrosis. There were thirteen women and two men with a mean age of 64 years old. The clinical assessment was performed using the American Knee Society Score system. The preoperative radiography was analyzed according to the size and stage of the osteonecrotic lesion and the osteoarthritic changes. Postoperatively, the presence of new osteonecrotic lesion, loosening of the implant, subsidence and arthritic changes was recorded. Results: The mean preoperative knee score and the knee function score was improved from 52.5 to 89.2 and 56.0 to 85.2, respectively. There was no new necrotic lesion in the lateral compartment, loosening of the implant, subsidence or arthritic change. Conclusion: UKA in patients with spontaneous osteonecrosis provided satisfactory clinical and radiological results in the short to medium term.