Arthrograms were performed on patients with rheumatoid arthritis of the wrist. Fifty cadavera and seven normal patients served as controls. Sixty arthrograms on thirty-eight patients with rheumatoid arthritis were studied.

The abnormalities demonstrated consisted of corrugated pattern of the synovial cavity (90 per cent), communication between radiocarpal and inferior radio-ulnar joint (70 per cent), between radiocarpal and mid-carpal joints (70 per cent), and between the wrist joint and the extensor tendon sheaths (21 per cent). One abnormality was suggestive of a diagnosis of rheumatoid arthritis and more than one was considered characteristic of the disease in the wrist joint. The abnormalities were present even before plain roentgenograms showed erosive changes.

The findings in the fifteen wrists operated on correlated well with the plain roentgenographic and arthrographic findings. The interosseous ligaments and articular discs were often destroyed as early on six months after the onset of disease. The soft-tissue involvement is an important cause of volar dislocation of the wrist and dorsal subluxation of ulna and tendon rupture.

The knowledge gained by arthrography has contributed evidence for early synovectomy of the wrist joint in rheumatoid arthritis.