Unilateral communication between the median and musculocutaneous nerves: implications for regional anesthesia

Anatomical variations of peripheral nerves are of great significance to anesthesiologists and pain specialists, as they can impact the safety and efficacy of interventional pain therapies, perioperative analgesia, and regional anesthesia. We report here an abnormal communication between the median nerve (MN) and the musculocutaneous nerve (MCN) in the left arm of an elderly male cadaver. The MCN, following its normal exit after piercing the coracobrachialis muscle and providing the branches to the biceps brachii muscle, joined the trunk of the MN proximal to the branch given off to the brachialis muscle. On its further course, it continued as the lateral cutaneous nerve of the forearm, supplying the skin of the lateral part of the forearm. Precise knowledge of variations in MCN and MN communications is vital during treatment of the traumatology of the shoulder joint, in plastic and reconstructive repair operations, as well as to the anesthetist performing pain management therapies on the upper limb.