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. A 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.