A closed head injury occurs when a person receives an impact to the head, but the skull does not fracture or displace. If the brain swells and has no place to expand, this can cause brain tissues to compress, causing further injury. Closed-head injuries, and other forms of mild traumatic brain injury, account for about 75 percent of the estimated 1.7 million brain injuries that occur annually in the United States. The annual financial burden of head injuries is estimated to be up to $100 billion.
Closed-head injuries can range from mild injuries to debilitating traumatic brain injuries.
• Concussion—a head injury resulting in temporary dysfunction of normal brain function.
• Intracranial hematoma—a condition in which a blood vessel ruptures causing a pool of blood to form around the brain.
• Cerebral contusion—a bruise to the brain tissue as a result of trauma.
• Diffuse axonal injury—an injury to the axon of the neuron. These injuries are frequently seen in car accidents and cause permanent damage to the brain.
Closed head brain injuries are caused by a blow or other traumatic injury to the head or body.
Common events causing closed head brain injury include the following:
• Falls are the most common cause of traumatic brain injury, particularly in older adults and young children.
• Motor vehicle collisions are the most common cause of closed head injuries for teenagers and young adults.
• About 20 percent of traumatic brain injuries are caused by violence, such as gunshot wounds, domestic violence or child abuse.
• Sports injuries, particularly from high-impact or extreme sports in youth.
• Explosive blasts and other combat injuries.
• Alcohol or drug use contributes to many cases of severe head trauma in younger patients.
• Bleeding in or around the brain, swelling, and blood clots can disrupt the oxygen supply to the brain and cause wider damage.
Symptoms associated with severe closed head injuries will normally present themselves immediately following trauma, while symptoms in milder cases may be delayed.
• Changes in emotional disposition and behavior
• Loss of consciousness
• Dilated pupils
• Difficulty breathing and other respiratory issues
• Nausea and vomiting
• Blurred or blacked out vision
• Slurred speech
• Lapses in memory