Synovial osteochondromatosis.

Primary or idiopathic synovial osteochondromatosis is an uncommon condition probably caused by synovial metaplasia and typically resulting in multiple calcified periarticular bodies. Synovial osteochondromatosis also may occur secondary to other joint disorders. This article reviews the pathogenesis, pathologic features, clinical features, and radiologic imaging of synovial osteochondromatosis. The differentiation of synovial osteochondromatosis from other conditions associated with periarticular calcified bodies is discussed.