Year Book: Synovial Chondromatosis

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Maurice, H. Crone, M. Watt, I. Abstract/Commentary: 1989 Year Book of Orthopedics. Article 4-88. Original Article: J Bone Joint Surg (Br). 1988 Nov. 70-B. pp 807-811. ABSTRACT Synovial chondromatosis is a rare condition in which foci of cartilage develop in the synovial membrane, bursae, or tendon sheaths of the joint as a result of metaplasia of the subsynovial connective tissue. Secondary calcification and ossification are common, and multiple cartilaginous loose bodies can be observed when metaplastic foci become pedunculated and detached. There is controversy about the removal of loose bodies and performing synovectomy. Data were reviewed on 43 patients who were classified in the Bristol Bone Tumour Registry as having synovial chondromatosis. These patients were aged 17 to 79 years. All had local pain. Twenty-five (58 per cent) also had diffuse swelling; 5 had a more discrete painful mass; and 14 (33 per cent) had mechanical symptoms of locking or clicking in the knee or elbow. Average duration of symptoms before operation was 4.5 years. A radiographic diagnosis was made when multiple juxta-articular radiodense shadows had the discrete stippled appearance of cartilaginous lesions. Radiopaque bodies were visible in 79 per cent of all cases. Eighty-eight percent of those with intra-articular disease had radiopacities throughout the affected joint, and 12 per cent had localized opacities. One patient had bone scanning for assessment of synovial activity in phases 1 and 2. Double-contrast arthrography was used to demonstrate both synovial nodularity and intra-articular loose bodies. Active synovial disease was seen in 38 patients (88 per cent), 25 of whom also had loose bodies. After a mean follow-up of 7 years of 37 patients (86 per cent), 5 (12 per cent) had recurrences. One of the 5 had incomplete excision of localized intra-articular disease, and the other 4 had generalized phase 2 intra-articular disease and an active synovium.