Dorsal metacarpal arteries

At a glance

English

Dorsal metacarpal arteries

Latin (TA2)

Arteriae metacarpeae dorsales

System

Artery

Region

Upper limb

Side

Paired, left and right

About the dorsal metacarpal arteries

The dorsal metacarpal arteries are the vessels of the back of the hand, one for each interosseous space between the metacarpal bones. The second, third and fourth usually come from the dorsal carpal arch, the arterial network on the back of the wrist built from branches of the radial and ulnar arteries. Each runs distally on its dorsal interosseous muscle, under the long extensor tendons, towards the cleft between two fingers.

The first dorsal metacarpal artery is different. It springs directly from the radial artery in the anatomical snuffbox region, just before that artery dives into the palm between the two bellies of the first dorsal interosseous. It runs on that muscle and supplies the back of the thumb and the radial side of the index finger.

Near the finger webs each dorsal metacarpal artery divides into two dorsal digital arteries for the facing sides of the neighbouring fingers. Along their course the vessels are tied into the palmar circulation in two places. Close to their origin, proximal perforating branches pass through the interosseous spaces to join the deep palmar arch; and near their distal ends, distal perforating branches link them with the superficial arch's common palmar digital arteries, or with the palmar metacarpal arteries.

Because of these links, blood can reach the back of the fingers from the deep and superficial palmar arches as well as from the carpal network, and the dorsal system is rarely deprived of supply. The arteries are small but surgically useful: the first and second dorsal metacarpal arteries are the basis of well-known island flaps taken from the back of the hand to cover defects of the thumb and fingers. The vessels also lie close to the extensor tendons, which is relevant when those tendons are repaired.

Course and supply

Arises from

The dorsal carpal arch for the second to fourth; the radial artery directly for the first.

Ends in

Each divides near a finger web into two dorsal digital arteries.

Supplies

Supply the dorsal interossei, the skin and tissues of the back of the hand and, through their digital branches, the back of the proximal parts of the fingers.