The posterior interosseous nerve and the radial tunnel syndrome: an anatomical study.

Twenty anatomical specimens were carefully studied in order to establish a possible connection between the posterior interosseous nerve and the radial tunnel syndrome. Our results show that the posterior interosseous nerve distal to the supinator muscle may be compressed by various structures. These include the distal border of the supinator muscle, the ramifications of the anterior and posterior interosseous vessels, and the septum between the extensor carpi ulnaris and the extensor digitorum minimi. The posterior interosseous nerve is also stressed during passive supination (elongation and rotation), and during passive pronation (compression). This suggests that the interosseous nerve distal to the supinator muscle should be explored in radial tunnel compression syndromes.