Case report 725. Posterior displacement of proximal end of the right radius and capitulum with supracondylar fracture causing a displaced fracture rather than a fracture dislocation.

An 11-month-old boy with a swollen, painful right elbow demonstrated a supracondylar fracture on plain film radiographic studies. Sonography was subsequently performed to exclude dislocation of the elbow and demonstrated the supracondylar fracture as well as a normal relationship of the capitulum and radius, signifying a displaced fracture without associated dislocation. A bone dislocation would generally require dosed reduction alone, whereas distal humeral epiphyseal separation usually requires open reduction or percutaneous (pin) fixation. This case demonstrates the utility of ultrasound in the evaluation of physeal disruption and dislocation in the elbow prior to ossification of the secondary centers of ossification.