Hi everyone. I wanted to spend a few moments on supracondylar fractures in children as this is one fracture that seems to be missed, when it’s not obvious and when first reading the Xray. It’s actually a pretty straightforward view of the elbow joint. The only catch is that the elbow must be at right angles ie., we must get good views. This month’s free lecture on resustv is on fractures such as this and given by Dr James Taylor, a great Emergency Physician, triathlete and an absolute gentleman.
Here’s a little summary below. Imagine that you had the Xray below. It is on a 6 year old boy who has fallen from monkey bars and has a painful elbow. This X-ray clearly shows the fracture. What do we do when the fracture is not obvious? Are there are clues that we can use?
Clue No 1: We need to ask if there’s a joint effusion? A small joint effusion is acceptable anteriorly, but any posterior effusion is indicative of an occult fracture.
The above Xray shows a large anterior and posterior fat pad sign. Indicates an occult fracture. The next thing to draw are two distinct lines: 1. The Radiocapitellar line and 2. The anterior humeral line.
THE RADIOCAPITELLAR LINE. A line drawn through the centre of the radial neck, will pass through the centre of the capitellum, if there is no fracture.
THE ANTERIOR HUMERAL LINE A line drawn along the anterior border of the humerus will pass through the middle third of the capitellum. If it passes through the anterior third of the capitellum, it means that the condyles have been displaced dorsally and there is a fracture.
You should also look at ossification centres: Internal Epicondyle, Olecranon, Lateral epicondyle. These appear roughly at years 1,3,5,7,9,11. However if all you did was look for the abnormal fat pad sign and looked at the radiocapitellar and anterior humeral line, this should give enough information, to not miss this fracture. I hope this helps.
Peter
