Although concussion is the most common type of brain injury seen in athletes, there is always the possibility that head impact may cause a more severe structural brain injury. This is a complication that is feared by all sports physicians and others involved in athletic care.

Acute subdural haematoma (ASDH) results from traumatic laceration to the brain, from bleeding from the cortical vessels into the subdural space or from acceleration–deceleration injury to the head that causes tearing of the bridging veins, resulting in clot formation in the subdural space between the arachnoid and dural meningeal layers. A subdural haematoma is often associated with some underlying parenchymal (brain) injury, including diffuse axonal injury. In contrast, extradural haematoma usually results from a skull fracture causing damage to a meningeal artery, which is situated between the dura and the skull. Classically, there is no significant parenchymal injury in extradural haematoma.

Subdural and extradural haematomas are distinct clinical entities that share some common elements in sports medicine yet also have certain individual peculiarities that are important in return-to-sports decision making.