Dorsal Cutaneous Ulnar Nerve Conduction

Preservation of sensation on the dorsoulnar aspect of the hand is a recognized clinical aid in localizing ulnar nerve lesions to the distal forearm or wrist, ie, below the origin of the dorsal cutaneous branch of the nerve.1-4This sensory branch leaves the main nerve trunk on an average of 6 to 8 cm proximal to the ulnar styloid and becomes cutaneous as it passes between the flexor carpi ulnaris tendon and the ulna. It supplies sensation to the dorsoulnar aspect of the wrist and hand and to the dorsal surface of the last two digits. Since unreliable, uncooperative, or disoriented patients may render the physical examination results inaccurate or equivocal, a more objective means of validating the aforementioned clinical sign is desirable. Jabre5recently reported a method measuring nerve conduction in the dorsal cutaneous ulnar nerve that accomplishes this purpose. Concurrently we developed a similar technique, and