From 1998 to 2006, 578 patients who were skeletally immature with proximal humerus fractures were treated at our institution. During that time period, 4 patients (0.7%) had associated brachial plexus and major peripheral nerve palsies. Average age at the time of injury was 12.3 years (range 10-14 years). Two fractures were physeal and 2 were metaphyseal. In all patients, the distal fracture fragment was displaced into the axilla, with resultant adduction and valgus malalignment at the time of injury. Two patients were treated with closed reduction and sling and swathe immobilization. One patient was treated with closed reduction and percutaneous pinning of the fracture. One patient was treated with sling immobilization without fracture reduction. All went on to bony healing with acceptable bony alignment. All patients were evaluated with serial physical examinations and radiographs to assess for neurologic recovery and bony healing. Average clinical and radiographic follow-up was 7.1 months (5-9 months). All patients demonstrated complete neurologic recovery by 5-9 months postinjury. All had neuropathic pain for at least 6 months after injury. No persistent neuropathic pain or functional limitations were seen at follow-up. Although rare, brachial plexus injury may accompany displaced proximal humeral fractures in patients who are skeletally immature. With careful attention to principles of fracture care, complete neurologic recovery may be expected within 9 months.