The dorsal cutaneous branch of the ulnar nerve An anatomic clarification with six case reports

Abstract

We studied the anatomy and pathology of the dorsal cutaneous branch of the ulnar nerve by dissecting 10 fresh cadaver upper limbs and reviewing 6 cases of injury or entrapment of the dorsal cutaneous branch of the ulnar nerve. In all of the cadavers and in our series of cases, several anatomical features were apparent: 1) the dorsal cutaneous branch of the ulnar nerve arises from the main ulnar nerve an average of 5.5 centimeters proximal to the head of the ulna; 2) the dorsal cutaneous branch of the ulnar nerve reaches the dorsum of the hand after coursing volar to the ulnar head; 3) there was no communication between the dorsal cutaneous branch of the ulnar nerve and the superficial sensory branch of the radial nerve; and 4) no volar branches were noted. Based on our experience, disorders of this nerve are more prevalent than previously reported. This clarification of the anatomy will help prevent unnecessary injury during surgery and will be valuable in the diagnosis of disorders of the dorsal cutaneous branch of the ulnar nerve.