Synovial chondromatosis of spine: case report and review of the literature.

Primary synovial chondromatosis is an uncommon, benign entity involving the synovial lining of larger joints. In this metaplastic process, islands of chondrocytes are clustered throughout the synovium, forming nodules that jut into the joint cavity. Clinical manifestations include pain, swelling, and decreased range of motion of associated extremities. Synovial chondromatosis may be confused with other degenerative joint diseases as well as chondrosarcoma. The occurrence of synovial chondromatosis in the spine is rare. Ten cases of this spinal variant have previously been published and this report represents the eleventh case. Here we briefly review the literature and discuss the histopathologic pitfalls and differential diagnosis.