Interosseous nerve

Interosseous Nerve

Diagram of the interosseous nerve and its branches. (Image from Gray's Anatomy)

The Interosseous Nerve is a branch of the Median Nerve that supplies the interosseous muscles of the hand. It is also known as the anterior interosseous nerve (AIN) to differentiate it from the posterior interosseous nerve (PIN), which is a branch of the radial nerve.

Anatomy

The interosseous nerve originates from the median nerve in the cubital fossa, just distal to the elbow. It travels down the forearm, running along the interosseous membrane between the radius and ulna. It supplies the deep muscles of the forearm, including the flexor pollicis longus, the radial half of the flexor digitorum profundus, and the pronator quadratus.

Clinical Significance

Damage to the interosseous nerve can result in Anterior Interosseous Syndrome (AIS), a condition characterized by weakness in the thumb and index finger. This can be caused by trauma, compression, or nerve entrapment.

See Also

• Median Nerve
• Interosseous Muscles
• Anterior Interosseous Syndrome