Massive synovial chondromatosis at the sinus tarsi

Abstract

Synovial chondromatosis (SC) is a rare, locally aggressive proliferative disorder affecting the synovial membrane of joints, tendon sheaths and bursae. There is a high incidence of local recurrence but malignant transformation is rare. Manifestations at the foot and ankle are very rare with only a few reported cases so far carrying the risk of delayed diagnosis or misdiagnosis. Here, we report a case of massive SC appearing as an increasingly painful mass over the sinus tarsi in a 52-year old female. Symptoms resolved completely after complete tumor resection. The diagnosis was confirmed by histopathology. A review of the literature is provided.