Details

Hand dissected to show the vascular and nerve supply of the palm and digits

GC.9160

Dissection of the volar aspect of the right hand of an adult with the distal fourth of the forearm showing the vascular and nerve supply of the palm and digits. In the forearm the radial artery is somewhat tortuous and as it commences to pass posteriorly it gives off the superficial volar artery which in this case lies superficial to the abductor pollicis brevis and flexor pollicis brevis muscles. The dissection also shows the radial artery winding posteriorly lateral to the carpus under cover of the tendons of the abductor pollicis longus and the extensor pollicis brevis and longus muscles, to the posterior aspect of the root of the thumb where it passes between the two heads of the first dorsal interosseous muscle to the palm of the hand where its union with the deep volar branch of the ulnar artery forming the deep volar arch is not shown in this dissection. As the radial artery disappears between the heads of the first dorsal interosseous muscle it gives off the arteria princeps pollicis which over the adductor pollicis muscle in this instance gives off the arteria volaris indicis radialis. Medial to this part of the radial artery there has been defined in this dissection the deep branch of the radial nerve as it crosses the extensor pollicis longus tendon towards the index finger. The ulnar artery is defined in the forearm lateral to the ulnar nerve and between the flexor carpi ulnaris and the superficial and deep flexors of the fingers. It enters the palm superficial to the transverse carpal ligament giving off in this part a volar carpal branch and just beyond the pisiform bone a dorsal carpal branch. It then forms the volar carpal arch and radially anastomoses with branches of the superficial volar and arteria princeps pollicis arteries. From the convex side of the arch are given off the common volar digital arteries which, bifurcating at the webs of the fingers, pass along the sides of the digits. The median nerve branches in the palm to supply the pollex, the index and middle fingers and the radial side of the ring finger. The ulnar nerve, bifurcating as it enters the palm, supplies the little finger and the ulnar side of the ring finger. A small branch of the ulnar nerve has been defined on the medial border of the wrist and hand as it passes posterior to the abductor digiti quinti, which, with the flexor digiti quinti brevis muscle, is adequately defined.