The ulnar nerve supplies half of the fourth digit and the entire fifth digit on the dorsal and palmar aspects of the hand. The ulnar nerve supply extends proximally to the wrist.
Dorsally, the median nerve supplies the tips of the first, second and third digits, as well as half of the fourth digit. The radial nerve supplies the remaining dorsal surface of these digits, extending proximally to the wrist.
On the palmar aspect of the hand, the median nerve supplies the first, second, and third digits, as well as half of the fourth digit. These nerve territories extend proximally to the wrist, sparing a small area at the thenar eminence supplied by the radial nerve.