Forearm injury in a 5 year old boy

A 5 year old right hand dominant boy was brought to the emergency department by his mother because of a painful and deformed left forearm. After slipping in the snow he had landed on his outstretched left hand. He had no relevant medical history. On examination, he was stable and the deformed arm was an isolated injury. There were no symptoms of neurovascular compromise and no evidence of skin compromise or breach. Plain radiographs were obtained (fig 1⇓). Fig 1 Anterioposterior (top) and lateral (bottom) radiographs of the forearm and elbow ### 1 What abnormality do the radiographs show? #### Short answer The radiographs show a minimally displaced proximal third ulna diaphyseal fracture and a radial head dislocation. The eponymous term for this injury is a Monteggia fracture of the forearm. #### Long answer The Monteggia fracture was first described by Monteggia in 1814.1 The radial head can be dislocated anteriorly, laterally, or posteriorly, and these injuries can be found in both adults and children. The Bado classification is used to describe the radiographic appearance of a Monteggia fracture (fig 2⇓). Fig 2 Bado classification of Monteggia fractures These injuries are often missed because they are rare, accounting for less than 5% of all forearm fractures. They …