Fusion of Musculocutaneous Nerve with Median Nerve in the Proximal One-Third of the Arm- A Case Report

During the routine undergraduate dissection of the anterior compartment of the right arm of a 48 years old male cadaver, a communication between musculocutaneous nerve and median nerve was encountered. The musculocutaneous nerve which normally arose from the lateral cord of the brachial plexus (C5, 6, 7) gave a branch to coracobrachialis in the proximal one-third of the arm without piercing it. After that, it was completely fused with the median nerve. The latter was formed normally by the union of the medial and lateral roots from the respective cords of brachial plexus anterior to the brachial artery. The other two muscles of the front of the arm viz. biceps brachii and brachialis were found to be supplied by median nerve. Knowledge of such variations in origin, course, and pattern of branching and distribution of nerves are useful not only for an anatomist but also for surgeons to avoid unnecessary damages during dissection. These types of variations of the nerves of the arm should be considered prior to traumatic evaluations and reconstructive interventions.