Injury to the brachial plexus in the adult is usually a closed injury and the result of considerable traction to the shoulder. Brachial plexus injury in the adult is an increasingly common clinical problem. Recent advances in neurosurgical techniques have improved the outlook for patients with brachial plexus injuries. The choice of surgical procedure depends on the level of the injury and the radiologist has an important role in guiding the surgeon to the site of injury. This article will describe the anatomy and pathophysiology of traction brachial plexus injury in the adult. The neurosurgical options available will be described with emphasis on the information that the surgeon wants from imaging studies of the brachial plexus. The relative merits of MRI and CT myelography are discussed.