Capitellum fracture


Capitellum fractures are rare elbow injuries accounting for less than one percent of fractures around the elbow. They are more common in females.

Mechanism of injury is usually a fall on the outstretched hand, the radius imparting a shearing force on the capitellum.

According to the Bryan and Morrey classification (with McKee modification), there are four types of capitellum fractures:

In this case, it is a type IV fracture. The characteristic finding on the lateral x-ray is the “McKee’s double-arc sign” because of the subchondral bone of the capitellum and lateral part of the trochlea.