UNUSUAL ABSENCE OF MUSCULOCUTANEOUS NERVE ALONG WITH MEDIAN NERVE FORMATION IN MID ARM

The lateral root of the brachial plexus issues three branches namely musculocutaneous nerve, lateral root and lateral pectoral nerve. The musculocutaneous nerve innervates all the muscles of anterior compartment of the arm. The median nerve is formed by union of lateral root of lateral cord and medial root of medial cord in axilla. But we found in one male cadaver, the absence of musculocutaneous nerve. The median nerve was formed by lateral root of lateral cord and medial root of medial cord as usual but in mid arm. In this case, the coracobrachialis is supplied by branch from lateral cord and biceps brachii and brachialis muscles were innervated by median nerve.The comprehension of these variations of musculocutaneous and median nerves are essential for clinicians for detecting weakness or paralysis of flexor muscles of arm due to injury to median nerve along with loss of flexion and supination of forearm, loss of sensation in the skin of lateral portion of the forearm and motor loss along the median nerve distribution