足関節痛を主訴とし診断に難渋した腓骨骨幹部類骨骨腫の1例

Osteoid Osteoma in the Fibular Shaft as a Cause of Ankle Pain : Case Report

　抄録：われわれは診断に難渋した腓骨骨幹部類骨骨腫の1例を経験した．症例は34歳，男性．主訴は右足関節痛．某整形外科医にて保存的治療を行っていたが，軽快しないため当科を紹介受診した．右足関節に異常所見はなかったが，骨シンチグラフィーで右腓骨骨幹部に異常集積を，また単純X線像上，同部の皮質骨の肥厚・膨隆とその中心部に骨透亮像を認めた．同部の切除術を施行し，右足関節痛は消失した．病理組織学的診断は類骨骨腫であった．術後約5年経過した現在，疼痛の再発は認めていない．本症例の診断には骨シンチグラフィーが有用であった．

　Osteoid osteoma is a relatively common benign bone tumor. It often occurs in the femur and tibia, and rarely in the fibula. We report a case of osteoid osteoma of the right fibula in a 34-year-old man who presented with pain in the right ankle at rest. There were no abnormal findings in the right ankle on physical examination or on plain radiographs. The patient continued to complain of the pain and that it had been interfering with his sleep for several months. A bone scan revealed a focus of intense uptake in the shaft of the right fibula, and plain radiographs showed an extensive sclerotic lesion with a central lucent portion corresponding to the area of increased uptake on the bone scan. Conventional wide excision of the fibula 3cm in length that included the radiolucent portion was performed. The results of the histological studies were compatible with osteoid osteoma. Resection of the lesion resulted in immediate and complete pain relief, and, at present, five years after surgery the patient is symptom-free.