6 yo with sore arm

A 6 year old boy falls from monkey bars and has a painful elbow.

What is the diagnosis? (Answer below)

Diagnosis

This is a pretty straightforward Supracondylar fracture. We can actually see the fracture as well as the anterior and posterior fat pad signs. However it isn’t always this clear. Lets look at these fractures.

Is there a joint effusion?

A fat pad sign anteriorly is normal. However if there is a fat pad sign anteriorly and posteriorly, this is abnormal and indicates a fracture.

There are two important lines to be able to draw:

1 Radiocapitellar line- a line through the centre of the radial neck should pass through the centre of the capitellum

2 Anterior humeral line-A line drawn along the anterior surface of the humerus, should pass through the middle third of the capitellum

Below is the radiocapitellar line

Below is the Anterior Humeral line

 

So putting this together in our 6 year old boy- he has anterior and posterior fat pads and a fracture, however if we were unsure of the fracture, the anterior humeral line intersects the anterior third of the capitellum, which also indicates a fracture. See below.