1978 年 27 巻 3 号 p. 435-438
A ten years old boy had complained of swelling of the lateral aspect of the left knee for about one month. Roentgenograms revealed an enlarged cystic lesion in the proximal metaphysis of the left fibula. At surgery, the cortex of the cystic legion was egg-shell thin and the cyst contained bloody fluid and a scanty amount of lining tissue around the inner wall. The lining substance of the cyst was curetted out without bone grafting. Clinically and pathologically, it was diagnosed as aneurysmal bone cyst.