Abnormal Pattern Of Brachial Plexus Formation: An Original Case Report

We encountered a brachial plexus with two cords (Medial & Lateral) and three abnormal communications. The lateral cord sent an abnormal branch to the medial cord as the medial root of median nerve emerged from the latter. A branch from the posterior aspect of the medial cord divided into the radial and axillary nerves. The musculocutaneous nerve sent an abnormal branch to the Median nerve at the level of mid-arm. There was also an abnormal communication between the ulnar and radial nerve at the mid-arm region. Knowledge of these variations is important in nerve entrapment syndromes involving different branches of brachial plexus.