Brachial plexus birth injury has an incidence of 0.9 per 1000 live births in the US, with the strongest associated risk factor being shoulder dystocia ¹. The classification of injury depends on the severity of the damage to the nerves. Neurapraxia, a relatively mild injury, results from compression or stretching and does not disrupt axonal continuity. The prognosis for a neuropraxic injury is favorable and requires little intervention. Neurotmesis, however, represents complete nerve discontinuity and is the most severe form of this injury with little chance of recovery of affected nerves.

This case involves complete avulsion of the C8 nerve root with associated pseudomeningocele formation. Additional brachial plexus roots and trunks appear thickened and hyperintense, indicating a low-grade injury ². Glenohumeral dysplasia, characterized clinically by exaggerated internal rotation and diminished external rotation of the shoulder, is a major cause of morbidity related to this class of injury and may be an indication for surgery in children with brachial plexus birth injury ³.

Case co-author: Alec Boyd (Loyola University)