Multimodal salvage treatment of a refractory pediatric pathologic femoral neck fracture in neurofibromatosis type 1: a case report

Background Neurofibromatosis type 1 causes intrinsic bone fragility and a biologically compromised healing environment. Pediatric femoral neck fractures are rare and prone to nonunion, and their management in neurofibromatosis type 1 is not established. Case presentation A 7-year-old boy with neurofibromatosis type 1 sustained a pathologic femoral neck fracture. Fixation with a single cannulated screw failed, with loosening and loss of reduction at 9 weeks. Revision surgery comprised debridement of interposed neurofibromatous tissue, fixation with five Kirschner wires, and allografting, followed by prolonged non-weight-bearing, low-intensity pulsed ultrasound, and selumetinib. Histopathology showed diffuse neurofibroma. Union was confirmed by radiography and computed tomography 12 months after revision. At the latest follow-up, 2 years and 5 months after the injury, the neck had healed in varus without osteonecrosis, and the limb-length discrepancy was 4 mm. Conclusions A multimodal salvage strategy achieved union in a refractory fracture associated with neurofibromatosis type 1. Because several interventions were applied concurrently, the independent effect of selumetinib remains uncertain.