Abstract
Introduction and aim: In the rheumatoid hand, a radial inclination of the wrist is commonly observed in the presence of an ulnar drift of the fingers. The question that remains is: Which came first? To find an answer to this question, we have studied the radiographs of 122 hand affected by rheumatoid arthritis.
Material and methods: In group I (44 hands), the disease was restricted to the wrist joint, which presented an average ulnar inclination of 15°, ranging from neutral to 43° of ulnar inclination.
In group II (13 hands), the disease was limited to the MP joints, with an average of 30° of ulnar inclination of the fingers, ranging from 10° to 70°. A compensatory radial inclination of 12° was observed at the wrist, ranging from 2° to 26°.
In group III (28 hands), both the wrist and MP joints were affected by the disease. The fingers presented an average ulnar inclination of 17°, ranging from 7° to 40°. The wrist presented an average radial inclination of 4°.
In group IV (34 hands) and V (3 hands), measurements were done before and after the finger deformity was corrected from an average of 45° to 7°, while the wrist corrected itself, without wrist balancing procedures, on an average from 30° to 2° of radial inclination.
Results: When only the wrist is involved, the metacarpals are always inclined towards the ulnar side. We have observed a radial inclination of the wrist only in the hands presenting an ulnar inclination of the fingers. When the ulnar drift of the fingers is surgically corrected, the radial inclination of the wrist will tend to correct itself.
Conclusion: It has been generally accepted that radial inclination of the metacarpals is one of the causes of the ulnar drift of the fingers, but from our studies the radial inclination of the metacarpals should not be considered the cause but rather a consequence of the ulnar drift of the fingers.
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