Pressure distribution in the distal radioulnar joint.

Measurement of the pressure distribution within the distal radioulnar joint was performed in fresh cadaver forearms at varying positions of forearm rotation. Axial loads of 0 N, 36 N, and 89 N were applied to the wrist flexors and extensors. At neutral forearm rotation and application of 89 N axial load, an average of 12.5% of the sigmoid notch area was in contact with the ulna. Analysis of the pressure plots reveals that in pronation, the pressure was concentrated in the dorsal portion of the sigmoid notch and that in supination the pressure was distributed in the palmar portion.