Pseudo-rheumatoid deformity in elderly osteoarthritic hands.

Three patients with severe ulnar deviation and metacarpophalangeal joint subluxation are described. They were all elderly women with interphalangeal joint osteoarthritis but no other rheumatic disease. The clinical appearance of the hands led to an incorrect diagnosis of rheumatoid arthritis in each case. Two were taking corticosteroids, predisposing to septic arthritis in one. Rheumatoid-like deformities may be common in the elderly.