We report the case of a 9-year-old boy who sustained a closed middiaphyseal plastic femoral deformation after a motor vehicle accident. The patient was treated nonoperatively with protected weightbearing to the involved extremity. Although he showed symptomatic improvement at early and intermediate followups, the patient did not show radiographic evidence of substantial injury remodeling and was left with a persistent anatomic valgus deformity 19 months postinjury. We were unable to identify prior reports of femoral plastic deformation in a child.