A head injury is any trauma to the scalp, skull, or brain. The injury may be only a minor bump on the skull or a serious brain injury. Any injury that results in trauma to the skull, or brain can be classified as a head injury. Injuries to your brain, skull, or scalp are all types of head injury. A head injury may be mild or severe depending on what caused it. Some injuries produce bleeding within your skull. Others cause damage on the outside of your head. These injuries may be in the form of lacerations, bumps, or bruises.
Head injury can be either closed or open (penetrating).
A closed head injury means you received a hard blow to the head from striking an object, but the object did not break the skull.
An open, or penetrating, head injury means you were hit with an object that broke the skull and entered the brain. This is more likely to happen when you move at high speed, such as going through the windshield during a car accident. It can also happen from a gunshot to the head.
Common causes of head injury include:
Symptoms of a head injury can occur right away. Or symptoms develop slowly over several hours or days. Even if the skull is not fractured, the brain can hit the inside of the skull and be bruised. The head may look fine, but problems could result from bleeding or swelling inside the skull.
The spinal cord is also likely to be injured in any serious trauma.
Some head injuries cause changes in brain function. This is called a traumatic brain injury.
Get medical help right away if the person: