Corpus: Posterior interosseous nerve

The posterior interosseous nerve is a terminal branch of the radial nerve that supplies a large portion of the extensors of the forearm.

The posterior interosseous nerve is the continuation of the deep branch of the radial nerve, originating in the cubital region. It begins after this nerve has penetrated the supinator muscle. Further on, it proceeds in front of the extensor pollicis longus muscle. It runs along with the posterior interosseous artery, on the interosseous membrane of the forearm in the dorsal interosseous space, moving distally towards the wrist.

Damage to the posterior interosseous nerve is the cause of supinator tunnel syndrome.