Atlas of Human Anatomy in Cross Section: Section 4. Upper Limb

Plate 4.32

Ronald A. Bergman, Ph.D., Adel K. Afifi, M.D., Jean J. Jew, M.D., and Paul C. Reimann, B.S.
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Various vascular components may be identified in this section. Elements of the superficial palmer arch (35) arise from the ulnar artery. A part of the deep palmer arch (21) is also seen. The deep arch arises from the radial artery. Palmar metacarpal branches (12, 17, 27) arise from the deep palmer arch. The first dorsal metacarpal (7) and princeps pollicis (6) arteries are also derived from the radial artery.

The ulnar artery proceeds from the proximal to the distal border of the flexor retinaculum accompanied by the ulnar nerve. It lies to the radial side of the pisiform bone and the ulnar side of the hook of the hamate (the bones forming a protective canal for the artery), which is covered by the palmer carpal ligament. Upon entering the palm it lies deep to palmaris brevis and the hypothenar fascia and divides into two branches, superficial and deep. The superficial branch, which forms the superficial palmer arch, descends a short distance into the palm and curves toward the thumb between the palmer aponeurosis and flexor tendons to form an arch. The arch may be located by a line projected transversely across the palm at the level of the metacarpophalangeal joint of the thumb. The superficial arch is crossed ventrally by palmer cutaneous branches of the ulnar and median nerves. The arch may be completed by anastomosing with the superficial palmer branch of the radial artery (30% of cases studied). In other cases, the arch is completed by joining the deep palmer arch by means of the princeps pollicis artery in 42% of individuals. A median artery may contribute to the arch in 8% of cases.

Branches of the superficial palmer arch include the common digital, proper digital, and palmer proper digital arteries.

The radial artery at the wrist turns dorsally, distal to the radial styloid process, crosses the radial collateral ligament, the scaphoid, and trapezium, and the ligaments uniting these bones, and disappears into the palm by perforating the first dorsal interosseous muscle between the proximal ends of the first and second metacarpal bones. In its path it is crossed by the tendons of abductor pollicis longus and extensor pollicis brevis, and by extensor pollicis longus. At the wrist, branches of the radial artery include the dorsal carpal and first dorsal metacarpal arteries. The radial artery enters the palm between the first and second metacarpal bones between the heads of the first interosseous muscle. It courses ulnarward across the palm, passing between the origin of the oblique and transverse heads of adductor pollicis muscle. It lies in the central compartment of the hand at the proximal end of the interosseous spaces, on the interosseous muscles. It is accompanied by the deep branch of the ulnar nerve and by a vena comitans. On the ulnar side it joins the deep ulnar artery to complete the deep palmer arch. The deep palmer arch lies about 1 1/2 cm proximal to the superficial arch. The branches of the deep palmer arch include princeps pollicis, radialis indicts, palmer metacarpal, recurrent branches, and proximal and distal perforating arteries.

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