[Measurement of the torsion of the two bones of the forearm: evaluation of tomodensitometric reference points].

Abstract

In order to evaluate the rotation following radial and ulnar fractures, the authors propose radial, ulnar and humeral landmarks for a CT scan measure of radial and ulnar torsion. In the ulna, the dorsal at the level of the proximal radio-ulnar articulation, as well as the bicondylar axis of the humerus seem to be fair landmarks. Distally, the styloid process is regularly identified and may serve as distal reference for the measure. In the radius, the ventral face of the distal epiphysis is always clearly visualized and seems to be a good landmark; the radial tuberosity, which was primarily chosen as proximal reference, is not consistently identified and cannot be used as landmark. The variation of position of the radial head with respect to the capitulum during pronation needs too know the amount of this movement before the measure if the bicondylar humeral axis is chosen as proximal reference.