Stress Fracture in Medial Femoral Plateau of Lateral Compartmental Osteoarthritis Knee after Unicompartmental Arthroplasty -A Case Report

• Published in: Japanese Journal of Rheumatism and Joint Surgery Vol. 17; no. 1; pp. 51 - 54
• Main Author: ARA, Yuki
• Format: Journal Article
• Language: English; Japanese
• Published: Japanese Society for Joint Diseases 1998; 日本関節病学会
• Subjects: medial tibial plateau; stress fracture; unicompartmental knee arthroplasty
• ISSN: 0287-3214; 1884-9059
• DOI: 10.11551/jsjd1982.17.51

A case of stress fracture of the medial tibial plateau after lateral unicompartmental arthroplasty was reported. The patient was a 67-year-old woman who suffered from lateral compart mental osteoarthritis of the right knee. Radiographs of the right knee showed osteoarthritic changes of grade 5 (Yokohama City University grading in weight-bearing radiogram) . A uni compartmental arthroplasty was performed to treat severe valgus deformity of the knee. The patient had sudden knee pain at 3 months after surgery. Radiographs were taken immediately, which showed a thin horizontal band of increased bone density 8 mm below the articular mar gin of the medial tibial plateau. At the same time, a bone scintigram was taken which showed increased uptake in the same site as the osteosclerotic band in the radiograph. From these findings, a stress fracture was suspected. The correction of the valgus limb alignment by which the weight-bearing axis might pass through the medial compartment of the knee, and postoper ative increase of the activities of daily life were thought to be the cause of this fracture. The treatment included the restriction of the patient's activities, and a knee cage was applied. At 6 months after surgery, there were no recurrence of the symptoms or refractures.