Rheumatoid arthritis is a systemic disease of unknown etiology characterized by progressive involvement of the joint synovial membrane, soft tissue, cartilage, bone, and blood vessels. It occurs more often in women than in men, with the peak incidence between thirty and forty years of age. The digital changes are secondary to the basic disease process and are of value in the differential diagnosis of arthritis. It may be that the peripheral polyneuropathy in rheumatoid arthritis is due in part to digital artery occlusion which produces degeneration of the peripheral nerves. The basic process is complex, as are the clinical findings. Method In a study of 50 rheumatoid arthritis patients by percutaneous brachial arteriography, it was found that 55 per cent showed an occlusive digital artery pattern, 35 per cent a hyperemic pattern, and 10 per cent a combined pattern. Between 20 and 30 cc of meglumine iothalamate 60 per cent was injected at a moderate rate by hand or by an automatic pressure injector at 40–60 psi injection pressure. An automatic cassette changer was used, and filming was started at the end of injection at 1.5-second intervals for twelve to eighteen seconds. A partial occlusion of the brachial artery for ten minutes prior to injection results in a reactive hyperemia, which can be utilized in examining some patients, particularly those with Raynaud's phenomenon. Tolazoline 20 mg may be given intra-arterially to produce vasodilatation of the arteries and to relieve spasm. Discussion One of the preferred changes in recognizing rheumatoid arthritis in the digits is the localized demineralization which occurs around the metacarpal heads. Periosteal reaction is seen proximal to the metacarpal head and the styloid process of the ulna. The demineralization is probably secondary to the vasculitis, which starts in the digital arteries and extends back to the metacarpal, radial, and ulnar arteries. Arterial spasm and digital artery occlusion with hyperemic areas around the metacarpal bones have been observed in the hand when the only radiographic change was demineralization. Hyperemia may be produced by vascular synovium in the joint and tendon sheaths or granulation tissue (Fig. 5). There is a slight difference in the vascular pattern from patient to patient. Even patients with early rheumatoid arthritis demonstrate some deficient digital artery circulation. Erosions are frequently surrounded by hyperemic areas. Collateral formation can be seen in the metacarpal region, attempting to supply the partially occluded or occluded digits. All fingers are involved with an equal frequency. Occlusive changes are associated with destructive and erosive bone changes (Fig. 1). They are more common in males and occur in all fingers with the same frequency. Hyperemic changes are more common in areas of little destructive and erosive change (Fig. 2).