Bilateral variations of brachial plexus involving the median nerve and lateral cord: An anatomical case study with clinical implications

During the routine dissection of upper limbs of a Caucasian male cadaver, variations were observed in the brachial plexus. In the right extremity, the lateral cord was piercing the coracobrachialis muscle. The musculocutaneous nerve and lateral root of the median nerve were observed to be branching inferior to the lower attachment of coracobrachialis muscle. The left extremity exhibited the passage of the median nerve through the flat tendon of the coracobrachialis muscle near its distal insertion into the medial surface of the body of humerus. A variation in the course and branching of the nerve might lead to variant or dual innervation of a muscle and, if inappropriately compressed, could result in a distal neuropathy. Identification of these variants of brachial plexus plays an especially important role in both clinical diagnosis and surgical practice.