A microradiographic and histological study of the manubrio-sternal joint in rheumatoid arthritis.

The manubrio-sternal joints (MSJs) of 10 male and 10 female non-rheumatoid subjects and of 11 subjects with RA were studied. Microradiography often revealed herniation of the intra-articular fibrocartilaginous disc into the cancellous bone and osteo-arthritic changes. In RA, erosive destruction of the articular surfaces was seen in six cases and in one subject the joint was ankylotic. Histologically the MSJ presented degenerative phenomena but no inflammatory changes in old non-rheumatic subjects. Active inflammation was visible in four joints from rheumatoid subjects, and in another four fibrous replacement suggestive of earlier inflammation was seen. The joints from non-rheumatoid subjects presented a histological joint cavity in nine cases, with or without synovial-like cells lining the cavity. A similar cavity was present in only one of the joints taken from rheumatoid subjects and there were inflammatory changes in the synovial tissue in this joint. It is suggested that involvement of the MSJ in RA m...