Intracapsular and paraarticular chondromas.

Intracapsular and paraarticular chondromas are rare benign tumors. The authors report four such lesions, three of which occurred about the knee and one at the hip. Radiographs showed calcified soft-tissue masses in the infrapatellar region of the knee in three patients. In the hip, the lesion was not visible on conventional radiographs. Three lesions originated from the joint capsule and one was extracapsular. These lesions should be differentiated from synovial chondromatosis and other calcified lesions occurring about the joints. After local excision, the tumors usually do not recur.