Nerves of the hand: Dorsal view (English)

Cutaneous innervation on the dorsum of the hand is mainly supplied by the ulnar and radial nerves. The dorsal branch of the ulnar nerve arises from the ulnar nerve approximately 5cm proximal to the wrist joint. It extends dorsally and divides into several dorsal digital branches. The dorsal digital branches of the ulnar nerve provide cutaneous innervation to the skin of the medial half of the dorsum of the hand and the skin on the dorsal aspect of the medial two and a half fingers. The superficial branch of the radial nerve extends dorsally and gives off several dorsal digital branches. This branch is also known as the "sensory branch" because of its primary role to provide sensation to the thenar eminence and dorsal aspect of the radial three and a half digits of the hand. Specifically, the dorsal digital branches of the radial nerve provide cutaneous innervation to the lateral two thirds of the dorsum of the hand and dorsal proximal two thirds of the lateral two and a half digits The 5th dorsal digital branch of radial nerve usually communicates with an adjacent ulnar dorsal digital branch of ulnar nerve which supplies the adjoining sides of the middle and ring fingers. The distal parts of the dorsal aspect of the lateral three and a half digits are supplied by branches of the median nerve.