A 4 month old Labrador puppy presented with acute onset left forelimb lameness. Radiographs were unremarkable.

CT showed a vertical fracture extending through the caudoproximal humeral metaphysis (large arrow Fig 1) and a thin horizontal hypodense line parallel to the proximal humeral  metaphysis (small arrows Fig 1 and large arrow Fig 2)

This is a Type II Salter Harris fracture but with a somewhat unusual extension of the fracture line horizontally through the proximal metaphysis. CT played a big part in evaluating this puppy’s problem!

Fig 1.

Fig 2.