A bone fracture is a medical condition in which a bone becomes cracked, splintered, or bisected as a result of physical trauma.

Classification

In medicine, fractures are classified as closed or open (compound) and simple or multi-fragmentary (formerly comminuted). Closed fractures are those in which the skin is intact, while open (compound) fractures involve wounds that communicate with the fracture and may expose bone to contamination. Open injuries carry an elevated risk of infection; they require antibiotic treatment and usually urgent surgical treatment (debridement). This involves removal of all dirt, contamination, and dead tissue.

Simple fractures are fractures that occur along one line, splitting the bone into two pieces, while multi-fragmentary fractures involve the bone splitting into multiple pieces. A simple, closed fracture is much easier to treat and has a much better prognosis than an open, comminuted fracture. Other considerations in fracture care are displacement (fracture gap) and angulation. If angulation or displacement is large, reduction (manipulation) of the bone may be required and, in adults, frequently requires surgical care. These injuries may take longer to heal than injuries without displacement or angulation.

In children, whose bones are still developing, there are risks of either a growth plate injury or a greenstick fracture. This type of fracture occurs because the bone is not as brittle as it would be in an adult, and thus does not completely fracture, but rather exhibits bowing without complete disruption of the bone's cortex. Growth plate injuries require careful treatment and accurate reduction to make sure that the bone continues to grow normally. Plastic deformation of the bone, in which the bone permanently bends but does not break, is also possible in children. These injuries may require an osteotomy (bone cut) to realign the bone if it is fixed and cannot be realigned by closed methods.

Orthopaedic surgeons have devised an elaborate classification system to describe the injury accurately and guide treatment. Description of a fracture starts by naming the bone and the part of the bone involved (e.g. shaft of the femur). It is important to note whether the fracture is simple or multifragmentary and whether it is closed or open. The geometry of the fracture is also described by terms such as transverse, oblique, spiral, or segmental. Other features of the fracture are described in terms of displacement, angulation and shortening. A stable fracture is one which is likely to stay in a good (functional) position while it heals; an unstable one is likely to shorten, angulate or rotate before healing and lead to poor function in the long term.