UCLA Radiological Sciences Proceedings

Primary synovial chondromatosis is an uncommon, benign synovial proliferative disorder rarely seen in children. The most commonly affected joint is the knee, followed by the hip. The symptoms of this condition are progressive and insidious and may include pain, joint stiffness, and swelling. Radiography is an appropriate first imaging modality that typically shows multiple calcified loose bodies within the affected joint space. Magnetic resonance imaging should then be performed to evaluate for the presence of noncalcified cartilaginous loose bodies and soft tissue involvement prior to surgical treatment that is necessary to prevent permanent joint damage. The recurrence of primary synovial chondromatosis is common, especially in cases of incomplete surgical excision. We report a case of primary synovial chondromatosis in a child. The diagnostic and the treatment considerations of the case are briefly discussed.