Middle collateral artery

The middle collateral artery (Posterior terminal branch of the deep brachial artery) is a branch of the deep brachial artery (arteria profunda brachii) in the upper arm. It arises as one of the two terminal branches of the profunda brachii — the other being the radial collateral artery.

Origin and Course

The middle collateral artery originates from the profunda brachii artery in the posterior compartment of the arm. It descends along the posterior aspect of the humerus, running within or adjacent to the medial head of the triceps brachii muscle. It courses posteriorly toward the elbow, where it passes superior to the olecranon.

Anastomoses

The middle collateral artery anastomoses with the interosseous recurrent artery (a branch of the posterior interosseous artery) posterior to the lateral epicondyle of the humerus. This anastomosis forms part of the periarticular arterial anastomosis of the elbow, a critical collateral network that ensures blood supply to the elbow joint and surrounding structures.

Clinical Significance

• The middle collateral artery is part of the collateral circulation around the elbow, which becomes clinically important in cases of brachial artery occlusion or ligation, as it helps maintain distal perfusion.

• It is relevant in surgical approaches to the posterior arm and elbow, including fracture fixation of the distal humerus, where knowledge of its course helps avoid iatrogenic vascular injury.

• Along with the radial collateral artery, superior ulnar collateral artery, and inferior ulnar collateral artery, it contributes to the rich anastomotic network that connects the brachial artery system proximally with the radial and ulnar recurrent arteries distally.