Abstract
Brachial plexus injuries are generally rare and a double-superior-trunk injury of the brachial plexus has never been reported before. We report the first case of a brachial plexus injury in a 43-year-old Chinese male with a double superior trunk. This was observed incidentally during an operation 1 month after initial traction injury sustained in a car accident. The double superior trunk of the brachial plexus was formed by the double roots of C5 and C6, respectively. Six months after discharge, the patient reported the recovery of most of the function of his left arm except the muscles innervated by the radial nerve. Two years after discharge, he reported almost full functional recovery of his left arm. We discuss what is known about anatomical variations of the brachial plexus, and the possible association between this novel brachial plexus anatomy and the almost complete functional recovery of the arm.