What classification is most commonly used, and what type would this be?
Classification is divided into three types each with a subtype (see related article on classification). It is based primarily on the degree and direction of displacement and presence of intact cortex. This would be a type IB fracture (minimally displaced, anterior humeral line still intersects part of the capitellum).
What is the 'sail sign'?
The sail sign describes the displacement of the anterior fat pad to create a shape reminiscent of a spinnaker sail on a boat. It is caused by a joint effusion and should make one suspect an occult fracture where a fracture is not demonstrated. In children, the sail sign is usually seen secondary to a supracondylar fracture.
How are supracondylar fractures treated?
Management depends on the type and degree of angulation. Type I fractures are stable and can be treated with cast immobilisation for ~3 weeks. Type II fractures require reduction and usually pinning. Type III fractures usually require open reduction and internal fixation.
AP and lateral radiographs of the elbow demonstrate a lucency across the distal humerus consistent with a supracondylar fracture. A line drawn along the anterior border of the humerus does not intersect the middle third of the capitellum, indicating that the fracture is somewhat posteriorly angulated.