Monteggia 'fracture'-dislocation with bowing of the ulna: a pitfall for the unwary emergency physician.

We recently encountered a child who fell on the left outstretched hand. She complained of left elbow pain subsequently and radiographs showed a supposedly isolated radial head dislocation. This was spontaneously reduced when the left forearm was extended for another radiograph. She was discharged from the emergency department with her left elbow in a long backslab, but returned within half an hour with recurrence of the radial head dislocation without repeat trauma. Only when the radiograph was reviewed was a subtle plastic bowing deformity of the ulna seen. This proved the axiom, that in forearm parallel long bone injuries, always consider the possibility of Monteggia or Galeazzi lesions when there is apparently isolated radial or ulna head dislocations. The clinician must always look very carefully for a fracture of the accompanying long bone, as even bowing 'fractures' might occur.