Anatomical Course and Destination
The vessel originates from the common interosseous artery (a. interossea communis). In the forearm, the anterior interosseous artery runs on the interosseous membrane (membrana interossea), passing deep to the flexor pollicis longus (m. flexor pollicis longus) and flexor digitorum profundus (m. flexor digitorum profundus).
Distally, it reaches the pronator quadratus (m. pronator quadratus), continuing into the palmar carpal network via the palmar carpal branch (r. carpeus palmaris).
In the lower third of the forearm, the anterior interosseous artery pierces the interosseous membrane from anterior to posterior to enter the posterior fascial compartment of the forearm. It also passes into the posterior region from the Pronator space (Pirogov's space) through a natural opening in the interosseous membrane.
Branches and Blood Supply
Along its course, the a. interossea anterior gives off branches to surrounding anatomical structures:
- Nutrient arteries — supply the radius and ulna.
- Muscular branches — supply the deep digital flexors, the flexor pollicis longus (m. flexor pollicis longus), the flexor digitorum profundus (m. flexor digitorum profundus), and the pronator quadratus (m. pronator quadratus).
- Branches to the median nerve — accompany the n. medianus in the upper third of the forearm; these include branches of the companion artery of the median nerve (a. comitans n. mediani).
Topographic Relations
On the anterior aspect of the forearm, the anterior interosseous artery runs alongside the radial (a. radialis) and ulnar (a. ulnaris) arteries. These arteries run parallel and possess muscular branches that anastomose with one another.
In the upper third of the forearm, the anterior interosseous artery accompanies the median nerve (n. medianus). In the lower third, it pierces the interosseous membrane anteriorly to posteriorly, entering the posterior fascial compartment. It contributes to collateral circulation in cases of injury or ligation of the major forearm arteries, including the posterior interosseous artery.
Clinical Significance
In caliber, the anterior interosseous artery is frequently comparable to the radial artery (a. radialis). A well-developed anastomotic network among the forearm arteries can compensate for restricted or completely interrupted blood flow in one of the main trunk arteries.