An unusual clinical finding is presented with a brief review of the literature. Synovial osteochondromatosis is typically a benign process involving metaplasia of the synovial intima and the formation of cartilaginous nodules that may eventually become ossified. Synovial osteochondromatosis should always be considered as a differential diagnosis whenever a patient presents with pain, swelling, and loss of function at or around a joint. Chondrosarcoma has been misdiagnosed, leading to radical and unnecessary amputation, because synovial osteochondromatosis has not been considered. Alternatively, synovial osteochondromatosis may degenerate to or be associated with a malignant process. When radiographs or more sophisticated investigative procedures, such as magnetic resonance imaging, fail to provide a conclusive answer, histologic findings provide the definitive diagnosis.