A Variation of the Musculocutaneous and the Median Nerve Anastomosis : A Case Report in Thai Cadaver

Abstract

This report describes a branch communicating between the musculocutaneous (MCN) and the median nerve (MN), which was detected during routine educational dissection of the right upper limb of a male cadaver in a gross anatomy class at Mahasarakham University Faculty of Medicine. After piercing the coracobrachialis muscle, the MCN runs downwards between the biceps brachii and brachialis muscles and gives branches to innervate both of these muscles. It then descends behind the brachial artery and communicates with the MN. The joining site we detected was located between the biceps brachii and brachialis muscles in the lower end of the arm, near the cubital fossa. The communicating branch also gave a filament to the pronator teres muscle. Since variations in the MCN and MN are frequent, and communicating branches between the MCN and MN are the most common, knowledge of this variation may help surgeons, anesthetists and neurologists to plan procedures at the arm, forearm and elbow following trauma or other medical problems.