We retrospectively reviewed 200 pediatric patients with acute type 3 extension type supracondylar fractures. Nineteen patients with nerve injuries were identified representing a 9.5% incidence of associated neurologic injury. All were associated with closed supracondylar fractures. The nerve injuries included seven anterior interosseus nerve palsies, four median nerve palsies, five radial nerve palsies and three ulnar nerve palsies. There were five vascular injuries, one was associated with a median nerve palsy. Three of these five patients required open exploration and one of these required arterial bypass. All other patients were treated with closed reduction and percutaneous pin fixation. Anterior interosseus nerve injury was the most common nerve injury in this series of pediatric supracondylar fractures. Diagnosis of this lesion may be subtle and was made in a delayed fashion in two patients in this series. Return of function occurred in all patients 6 to 16 weeks after the injury without surgical intervention. Anterior interosseus nerve injury may be more common than previously recognized and warrants a careful initial neurologic examination to identify this lesion.