A plain radiograph showing chondrosarcoma involving distal femur. The lesion is somewhat circumscribed and shows mineralization and endosteal scalloping. Mineralization is seen in approximately 75% of cases. Some form of cortical abnormalities (endosteal scalloping or erosion, frank cortical destruction) are seen in the vast majority of chondrosarcomas. Expansion of the bone and a soft tissue mass are other findings that may be seen radiographically. The most frequently involved sites include the trunk and the upper ends of femur and humerus. Chondrosarcomas are rare in the distal portions of the extremities.