The Journal of Bone and Joint Surgery

Image Quiz
Elbow Pain and Swelling in a Three-Month-Old Infant After a Fall (continued)
Answer: Fracture-separation of the distal humeral physis.
Fig. 1	Fig. 1 Anteroposterior and lateral radiographs of the right elbow, showing fracture-separation of the distal humeral physis. For larger view, click on image
Diagnosis of fracture-separation of the distal humeral physis can be difficult in neonates and young infants because the distal humeral ossification centers have not yet become visible. Evaluation of the relationship of the distal humeral metaphysis to the proximal radial and ulnar metaphyses is the key to the diagnosis of this injury. With fracture-separation of the distal humeral physis, the radius and ulna maintain anatomic alignment with respect to each other and the distal humeral epiphysis, but are shifted together posteromedially (in most cases) with respect to the humeral metaphysis.
The patient was treated with operative closed reduction, pinning with two laterally placed percutaneous Kirschner wires (Fig. 3), and a long arm splint at approximately 60° of flexion.
Fig. 3	Fig. 3 Radiographs showing the elbow after closed reduction and placement of two Kirschner wires. For larger view, click on image


What additional workup should be considered for an infant with this diagnosis?