Classification of communications between the musculocutaneous and median nerves.

In 16 out of 79 cadavers 22 communications were found between the musculocutaneous and median nerves. In six subjects they were present bilaterally. There were three types, based on the sites of communication. Type I: The communication was proximal to the entrance of the musculocutaneous nerve into coracobrachialis (9/22); Type II: The communication was distal to the muscle (10/22); Type III: The nerve as well as the communicating branch did not pierce the muscle (3/22). Bilateral communications were not necessarily of the same type. The possible clinical implications of these communications (relating either to the surgical approach to the shoulder joint, or to entrapment syndromes) are discussed.