Bursa formation an synovial chondrometaplasia associated with osteochondromas

Two adult patients who had synovial chondromatosis occurring within bursae formed around osteochondromas are described. In spite of marked cellular atypia of the cartilage cells, the clinical course was unremarkable, pointing out the discrepancy between histologic changes and subsequent behavior in this condition. Histologic features, in addition, are not always helpful in distinguishing primary from secondary chondrometaplasia.