Abstract
Results of arthrograms of the shoulder were evaluated in 29 patients (32 shoulders) with rheumatoid arthritis. Arthrograms were evaluated according to DeSmet's classification. Arthrographic findings were as follows: diffuse nodular filling defects (66%), irregular capsu-lar attachment (69%), bursal filling defects (41%), rotator cuff tear (41%), lymphatic drainage (25%), frozen shoulder (25%), biceps sheath “ampulla” (13%), and synovial cyst (13%) . Contrast medium in the rotator interval region was observed in two cases which did not show any indication of rotator cuff tear. We classified synovial cysts into 3 types: Type 1, 3 cases; Type 2, 6 cases; and Type 3, 4 cases. The pathomechanism of the synovial cyst in the rheumatoid shoulder was suggested to include valve mechanism, which can be observed in popliteal cysts of the rheumatoid knee. Rotator interval and synovial cyst should be paid attention to when the destruction process mechanism of the rheumatoid shoulder is discussed.
