The influence of a joint orthosis on the grip force of the rheumatoid hand.

Distribution of force was studied for the distal, medial and proximal digits of 60 patients with rheumatoid arthritis during a cylindrical grip before correction of the flattened transverse arch of the hand and after its correction using a felt pad placed under the capitulum of the third metacarpal bone, and also before and after the placing of a wrist band. The cylindrical grip involving 22 degrees of ease of movement is the best indicator of hand function and deteriorates most (in approximately 80-90%) in cases of disease.