[2] It is accompanied by the palmar interosseous branch of the median nerve, and overlapped by the contiguous margins of the flexor digitorum profundus and flexor pollicis longus muscles, giving off in this situation muscular branches, and the nutrient arteries of the radius and ulna.

At the upper border of the pronator quadratus muscle it pierces the interosseous membrane and reaches the back of the forearm, where it anastomoses with the dorsal interosseous artery.

Before it pierces the interosseous membrane the anterior interosseous sends a branch downward behind the pronator quadratus muscle to join the palmar carpal network.

The anterior interosseous artery supplies the deep layer of the anterior compartment of the forearm, including the flexor digitorum profundus, flexor pollicis longus, and pronator quadratus muscles.

This article incorporates text in the public domain from page 596 of the 20th edition of Gray's Anatomy (1918)