Head | Neurology | Head Injury (Symptom)
A head injury is a broad term that describes a vast array of injuries that occur to the scalp, skull, brain, and underlying tissue and blood vessels in the head. Head injuries are also commonly referred to as brain injury, or traumatic brain injury (TBI), depending on the extent of the head trauma. Blows to the head most often cause brain injury, it is important to remember that the face and jaw are located in the front of the head. Brain injury may also be associated with injuries to these structures. It is also important to note that a head injury does not always mean that there is also a brain injury.
People suffer head injuries most frequently due to falls, motor vehicle crashes, colliding or being struck by an object, and assaults. Falls and being struck are the most common causes of head injury in children.
Head injuries may be closed or open. A closed (non-missile) head injury is where the dura mater remains intact. The skull can be fractured, but not necessarily. A penetrating head injury occurs when an object pierces the skull and breaches the dura mater. Brain injuries may be diffuse, occurring over a wide area, or focal, located in a small, specific area.
If intracranial hemorrhage occurs, a hematoma within the skull can put pressure on the brain. Types of intracranial hemorrage include subdural, subarachnoid, extradural, and intraparenchymal hematoma. Craniotomy surgeries are used in these cases to lessen the pressure by draining off blood. If the impact causes the head to move, the injury may be worsened, because the brain may ricochet inside the skull causing additional impacts, or the brain may stay relatively still (due to inertia) but be hit by the moving skull (both are contrecoup injuries).