Proximal femoral physeal fractures in children: a rare abusive injury

Background: Proximal femoral physeal fractures are rare in abused children. Recognition may be hampered due to their rarity and lack of an ossified femoral head. Prompt diagnosis and treatment are essential to preventing coxa vara. Objective: To demonstrate the radiographic features of proximal femoral physeal fractures both with unossified and ossified femoral heads. Materials and methods: We reviewed our Institutional Review Board-approved 21-year radiology database of 2,206 children who had a skeletal survey as part of their medical evaluation for possible abuse. Cases of proximal femoral physeal fractures were identified. Results: Eight patients, ages 2.5 to 26 months, with 10 fractures were found, yielding a prevalence of 0.4% (8/2,206). In all fractures, there was lateral displacement of the proximal femur. In three fractures, the femoral head was not ossified, simulating a hip dislocation. The intra-articular location of the femoral head was verified by ultrasound or abdomen computed tomography. Subperiosteal new bone formation was present in six fractures, all non-weight-bearing patients. The femoral head was ossified in seven cases, all with medial rotation of the femoral head. Metaphyseal irregularity was present in three of four fractures of the weight-bearing patients; two of three also had metaphyseal scalloping resembling osteomyelitis. The three with metaphyseal irregularity developed coxa vara. Conclusion: Proximal femoral physeal fractures are rare in abuse cases. All present with lateral displacement of the proximal femur. With an unossified femoral head, it can simulate hip dislocation, which can be clarified with hip sonogram. Metaphyseal irregularity appears to be a feature in weight-bearing patients.