The nerve of Henle: an anatomic and immunohistochemical study.

The topography of the nerve of Henle was reviewed. Fifty-two human cadaveric upper extremities were studied. In 30 (58%) the nerve was well defined; in 22 (42%) its origin from the ulnar nerve was unidentifiable. The palmar cutaneous branch of the ulnar nerve separated from the ulnar nerve 5 to 11 cm distal to the medial epicondyle of the humerus to divide into its terminal branches in the distal forearm. Four patterns were detected: ulnar, radioulnar, vessel-related, and radial. These shared a consistent vascular branch, which sent 2 branches to the ulnar artery just proximal to the distal ulnar tunnel. Using a tyrosine hydroxylase antibody-based immunohistochemistry technique the nerve was shown to carry sympathetic fibers. Motor fibers were ruled out with Karnovsky's stain, which was used in combination with the tyrosine hydroxylase method in 10 specimens.