Closed Head Injury

Bumps, bashes, and blows to the head are very common and often require little more than ice on bruises or bandages on cuts; however, sometimes the injuries are not on the outside of the head at all. Although the skull has not been opened and no injury is visible, the brain can be damaged. This is called closed head traumatic brain injury.

Closed head injuries are the most common and serious types of head injuries. In closed head injury, brain swelling and pressure can seriously and permanently destroy delicate brain tissue and nerve cells.

Closed head injury can be caused by blows to the head, rapid acceleration/deceleration of the head (whiplash), or the head suddenly striking an object. Brain injury can be relatively mild or severe and fatal. Closed head traumatic brain injuries include concussion, contusion, diffuse axonal injury, and hematoma.

Concussion

Concussion is a mild form of closed head traumatic brain injury and is very common. In the United States, about 600,000 people per year seek concussion treatment. Luckily, the brain is capable of recovering from concussion. Concussion is a brain injury that temporarily disturbs or alters normal brain function. For a few seconds or minutes after sustaining concussion, a person may not be able to concentrate, may be confused, or may completely lose consciousness. People with mobility problems may have difficulty standing or walking and may fall and often sustain concussion. People who are active in high impact contact sports, like football or boxing, also often sustain concussion.

Concussion symptoms include headache, dizziness, nausea, insomnia, dilated pupils, and restlessness. Temporary memory loss is common as well. Depending on traumatic brain injury severity, these symptoms can last for several days or weeks. The associated brain swelling can be dangerous if a person is unconscious for more than a few minutes or is difficult to awaken. These can be signs of more severe brain injury.

Contusion

Contusion is brain tissue bruising. Rapid acceleration/deceleration of the head (whiplash) or a blow to the head can cause contusion. These events can cause the brain to scrape over sharp skull protrusions, which shear and cut delicate brain tissue. Boney, sharp skull ridges are located on the inside of the forehead (frontal lobe) and the eye socket (ocular orbit). Contusions commonly occur on the frontal and temporal lobes.

A person who sustains contusion can experience concentration, emotional, and memory problems after injury. Contusions can increase intracranial pressure (ICP), or pressure inside of the skull from brain swelling, and hemorrhage, two potentially life-threatening complications of traumatic brain injury.

Diffuse Axonal Injury

Diffuse axonal injury profoundly damages brain tissue. Diffuse axonal injury usually results from twisting or rotational forces. Car accidents, sporting accidents, and child abuse commonly cause diffuse axonal injury. When the head is rapidly accelerated or decelerated, tissues of differing densities and distances slide over one another, stretching and shearing axons (brain nerve fibers), which prevents communication between brain cells.

Diffuse axonal injury most often results in coma; nearly 90 percent of these coma victims never regain consciousness.

Hematoma

Hematoma is bleeding or a collection of blood inside of the skull. In closed head injuries, hematoma is a troubling brain injury. Because the skull has not been opened up, blood and brain swelling pressure has nowhere to escape. As pressure increases, brain tissue is destroyed and damaged.

The most common type of hematoma is subdural hematoma, a collection of blood between the tough, leathery membrane that lines the skull cavity and spinal column (dura) and the brain. Subdural hematoma occurs in about 20 to 40 percent of closed head injury victims. Violent head motion from whiplash or blunt impact causes veins in the brain to tear. Overlying skull fractures cause other hematomas.

Closed Head Injury Complications

In closed head injuries, immense brain pressure and tissue swelling cause severe complications. Mild closed head injury victims may experience long-term problems with thinking, memory, reasoning, sight, hearing, touch, taste, smell, emotions, aggression, depression, or insomnia. About 40 percent of closed head injury victims develop post-concussion syndrome (PCS). PCS symptoms include memory problems, migraines, sleeping problems, anxiety, and depression. These symptoms can last for a few weeks after the injury. More severe closed head traumatic brain injury complications include coma and paralysis. Epilepsy or seizures are common for many people.

A particularly devastating closed head injury complication is increased intracranial pressure. Intracranial pressure is the amount of force the brain, blood, and cerebrospinal fluid (which cushions the brain and spinal cord) exert on the skull. When injured, the brain swells, accumulates extra fluid, and increases in size, thus increasing pressure.

In closed head injury, the skull is not opened; fluid and pressure cannot escape the confines of the skull, and pressure rapidly builds. Increased intracranial pressure destroys brain tissue and restricts blood and oxygen flow. Traumatic brain injury victims often die from this critical complication.

Closed Head Injury Treatment

To treat the injury, head injury victims are held at a hospital overnight or for several days. Because related brain swelling causes pressure in the skull, an intracranial pressure (ICP) monitor is surgically inserted into the skull. Sometimes closed head injury victims are given medication to prevent or to treat seizures. For closed head injuries, antibiotics are not usually required.

To decrease intracranial pressure and treat any bleeding in the brain or skull, surgery is often necessary. A surgeon will work to decompress the brain and to release excess fluid. A traumatic brain injury victim may also be put on a ventilator, or artificial breathing machine, and given medication or repeated spinal taps to remove fluid and reduce pressure. Intracranial pressure is serious and often fatal.

Closed Head Injury Rehabilitation

People who survive closed head traumatic brain injury often need rehabilitation. Rehabilitation programs aim to restore basic cognitive function, such as memory, speech, and decision making. Mild closed head injury victims may not need long-term rehabilitation, whereas more severe closed head injury victims may need extensive rehabilitation.

A physiatrist, a physician that specializes in physical medicine and rehabilitation, evaluates a closed head traumatic brain injury victim and prescribes appropriate rehabilitation. A neuropsychologist, a doctor who specializes in brain behavior, treats a person's changes in thinking and behavior following brain injury. A physical therapist works alongside the neuropsychologist to re-establish mobility and simple functions like standing up or walking, brushing one's teeth, and using the bathroom.

Closed head traumatic brain injury is a serious condition. There are many other ways in which traumatic brain injury may occur. Read more articles on this site to learn about other causes, treatments, and types of traumatic brain injury.

[Last revision: March 2007]