Handedness and deformities, radiographic changes, and function of the hand in rheumatoid arthritis.

The correlation of handedness with deformities, radiographic changes, and function of the hand was studied in a large group of patients with rheumatoid arthritis and a dominant right hand. There was no significant difference in the proportion of patients who had swan neck deformity, boutonnière deformity, uncorrectable ulnar deviation, and flexor tenosynovitis in the dominant and non-dominant hands. There were significantly greater radiological changes in the dominant hand, however, and the middle and index fingers were most severely affected. The severe involvement of these fingers may be related to their greater use in daily activities. There was also more severe functional impairment in the dominant hand.