Unilateral Absence of Musculocutaneous Nerve and a Communication between Medial and Lateral Cord of Brachial Plexus: A Case ReportManavalan Mahima Sophia*, Kalpana Sriram Ramachandran, and Alagesan Anupriya
Department of Anatomy, Sri Muthukumaran Medical College & Research Institute, Chikkarayapuram, Near Mangadu, Chennai-600069.Tamilnadu, India
Variation of musculocutanous nerve at the level of brachial plexus is common. The musculocutaneous nerve is a branch from lateral cord of brachial plexus. It supplies flexor muscles of the elbow and skin on the lateral aspect of forearm. During routine dissection of the upper limb of a seventy year old adult male cadaver, a communication between medial and lateral cord of brachial plexus in the left axilla was noted. On the same side in the arm, musculocutaneous nerve was absent. The muscles supplied by musculocutaneous nerve were innervated by branches of median nerve and a muscular branch to the brachialis muscle continued as lateral cutaneous nerve of forearm. There was no variation in the musculocutaneous nerve on the right side but there were two communicating branches between musculocutaneous and median nerve. Knowledge of such variation has clinical significance in median nerve injury and also helpful in diagnostic clinical neurophysiology, surgical procedures and management of shoulder and arm trauma. Though such variations are common, it is of clinical significance for radiologists, anaesthetists and surgeons besides of being academic interest for the anatomists.