Radial collateral artery

At a glance

English

Radial collateral artery

Latin (TA2)

Arteria collateralis radialis

System

Artery

Region

Upper limb

Side

Paired, left and right

About the radial collateral artery

The radial collateral artery is one of the two terminal branches of the profunda brachii, the deep artery of the arm. The profunda leaves the brachial artery high in the arm and winds round the back of the humerus with the radial nerve in the radial (spiral) groove. On the lateral side of the bone it divides into a middle collateral branch, which descends behind, and the radial collateral artery, which is sometimes called its anterior descending branch.

From its origin the radial collateral artery follows the radial nerve through the lateral intermuscular septum into the front of the arm. It then runs down between brachialis and brachioradialis, still beside the nerve, and reaches the front of the lateral epicondyle of the humerus. There it meets the radial recurrent artery, which has climbed up from the radial artery in the forearm.

This meeting point is one of the links of the anastomosis around the elbow, a ring of vessels joining branches of the brachial artery above the joint with recurrent branches from the radial and ulnar arteries below it. The middle collateral artery joins the interosseous recurrent artery behind the lateral epicondyle in the same way, while the superior and inferior ulnar collateral arteries form the matching links on the medial side. Together these channels let blood bypass the elbow when the joint is bent or the main artery is blocked.

Because of the anastomosis, the brachial artery can be tied below the origin of the profunda brachii and the forearm still receives blood, although slowly. The artery's close company with the radial nerve means that the two are at risk together in fractures of the humeral shaft. Surgeons also use the vessel to nourish the lateral arm flap, a skin and fascia flap raised on the back of the arm for reconstructive work.

Course and supply

Arises from

A terminal branch of the profunda brachii (deep brachial) artery, given off on the lateral side of the humerus after that vessel has wound through the radial groove.

Ends in

Descends in front of the lateral epicondyle between brachialis and brachioradialis and ends by joining the radial recurrent artery in the elbow anastomosis.

Supplies

Supplies brachioradialis, brachialis, the radial nerve and the lateral side of the elbow, and forms a collateral channel around the joint.