When evaluating an elbow plain film, what is the anterior humeral line and what is it's significance?
The anterior humeral line: On a true lateral film, this line is drawn along the anterior aspect of the humeral shaft on the lateral radiograph. This line passes through the middle one third of the capitellum in bones that are not injured. It is very useful for detecting subtle fractures.
Fractures (i.e. supracondylar) usually result in displacement of the capitellum posteriorly, thus, the anterior humeral line passes through the anterior one third or entirely anterior to the capitellum.