Fracture-separation of the distal humeral epiphysis in newborn is a rare entity, usually the result of a traumatic delivery. It can mimic elbow dislocation and, due to the absence of ossification of the epiphysis at that time, cannot be diagnosed radiographically. However, ultrasound is an important diagnostic tool for this purpose because it is able to clearly visualize the cartilaginous epiphysis. In addition, it allows the differential diagnosis with posterior elbow dislocation whose therapeutic management and prognosis are different. We report the case of a preterm newborn in which a fracture-separation of the distal humeral epiphysis was diagnosed with the help of sonography. The purpose of this report is to emphasize the utility of echography as a cheap, available, and noninvasive tool for the evaluation of the nonossified epiphysis in the newborn elbow. © 2013 Elsevier Inc.