Report A variant course of lateral cord of brachial plexus;communication between median & musculocutaneous nerves

In lateral side of the lateral cord is part lateral pectoral nerve and musculucutaneous nerve. Before piercing of the coracobrachialis muscle. the cord gives a muscular branch to this muscle from its lateral side. After sending muscular branches to biceps brachii and brachialis it pierces the coracobrachialis muscle and coures downwards for a long distance at the middle of the arm into lateral forearm skin, that named as lateral forearm cutaneous nerve. Finally it is shape at the middle of the arm, lateral root median nerve. variation in the course and branching of lateral cord is important for surgical and radiologists specially in relation to surgeries involving this region. Case report: During routine dissection of upper limbs on an adult male cadaver for education medical students of Zabol Medical Sciences University, variation in the course and branching of lateral cord was noted. The lateral cord was found to pierce the coracobrachialis muscle. Before piercing, the cord gave a muscular branch to this muscle from its lateral side. After emerging from the muscle, it divided at the middle of the arm into two branches.The medial branch corresponded to the lateral root of the median nerve, where as the lateral branch corresponded to the musculocutaneous nerve. The latter coursed giving muscular branches and finally it bifurcated giving two terminal branches. The lateral branch formed the antebrachial cutaneous, while the medial branch coursed downwards for a short distance deep to the brachial artery. Interestingly, this branch joined the median nerve forming communication with it. Discussion and During embryologic development of the procedure generated this variation in the course and branching of lateral cord of brachial plexus. obviously, Such intercommunications between musculocutaneous nerve and median nerve have great clinical importance in the diagnosis of related neurological disorders and surgical procedures in this region.