1993 年 42 巻 2 号 p. 877-880
We reported a case of femoral shaft erosion with the patella wrapped around the femur associated with calcium pyrophosphate crystal deposition disease. There was little synovial proliferation on the femoral erosion site. Histologically there were no inflammatory changes in the synovium and bone cortex in the area of the femoral erosion. Acceleration of osteoclastic bone resorption on the bone cortex in the erosion was obsened. We concluded that the upper end of the patella contacted chronically with the femur, so that bone resorption was accelerated in that part of the femur, leading to femoral erosion.