Palmar arterial arches
Arcus palmaris superficialis et profundus
Also known as: superficial palmar arch, deep palmar arch
The palmar arches are two arterial arcades in the palm. The superficial arch comes mainly from the ulnar artery and the deep arch mainly from the radial artery. Because the two are connected, the fingers have a double blood supply.
Overview
Superficial palmar arch. This lies just under the palmar aponeurosis, in front of the long flexor tendons and the branches of the median nerve. Its most distal point lies at about the level of the distal border of the fully extended thumb (Kaplan's cardinal line). It is formed mainly by the ulnar artery and completed by a branch of the radial artery. It gives rise to the common palmar digital arteries, which divide into the proper digital arteries of the fingers.
Deep palmar arch. This lies about 1 cm closer to the wrist, on the bases of the metacarpals and the interosseous muscles and deep to the flexor tendons. The deep branch of the ulnar nerve runs in its curve. It is formed mainly by the radial artery and completed by the deep branch of the ulnar artery. It gives off palmar metacarpal arteries, which join the common digital arteries, and perforating branches to the back of the hand.
Function
- Supply the palm and fingers, with two connected sources so that the hand stays perfused if one artery is blocked.
Clinical significance
Palmar lacerations
A cut through a palmar arch bleeds from both ends because the arch is fed from both sides. Pressure is applied and the vessel is usually repaired or tied off at both ends.
Surgical landmarks
Kaplan's cardinal line and the line of the extended thumb mark the position of the superficial arch. Surgeons use them to avoid the arch during carpal tunnel release.
Compiled from standard anatomy and physiology references — see the Cardiovascular System sources. For education only; not medical advice.