Case report: Bilateral femoral neck fractures in a child and a rare complication of slipped capital epiphysis after internal fixation.

BACKGROUND: Bilateral traumatic femoral neck fractures are uncommon in children. The most commonly reported complications are nonunion, avascular necrosis of the femoral head, and chondrolysis. Slipped capital femoral epiphysis (SCFE) associated with nonunion after percutaneous partially threaded cancellous screw (PTCS) fixation of the fracture is an unreported complication. CASE DESCRIPTION: We describe a 10-year-old boy who had bilateral femoral neck fractures secondary to a fall from a height. The patient was treated with percutaneous PTCS fixation on both sides and achieved union on the right side in 3 months, however, a nonunion and SCFE developed on the left side 5 months after the initial surgery. Management of the nonunion and SCFE with PTCS and nonvascularized fibula graft led to union. Eighteen months after the initial injury, the patient achieved a pain and limp-free gait. LITERATURE REVIEW: A literature review shows avascular necrosis, posttraumatic coxa vara, premature physeal closure, nonunion, chondrolysis, infection, and implant failure as complications of operative management of femoral neck fractures. SCFE has not been previously reported. PURPOSES AND CLINICAL RELEVANCE: This case highlights the need for close followup of adolescent patients with PTCS fixation for femoral neck fractures.