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Traumatic brain injury

Concussion; Brain injury - concussion; Traumatic brain injury - concussion; Closed head injury - concussion

A traumatic brain injury (TBI) can occur when the head hits an object, or a moving object strikes the head. There are three types of TBI:

A TBI can affect how the brain works. The degree of impaired brain function and other symptoms and how long they will last depends on how severe the TBI is. A TBI may lead to headaches, changes in alertness, loss of consciousness, memory loss, and changes in thinking. Moderate to severe TBIs can cause life-long health problems.

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Causes

TBIs can be caused by:

Penetrating injuries to the skull, such as from a gunshot or other trauma can cause moderate to severe TBIs.

A big movement of the brain (called jarring) in any direction can cause a person to lose alertness (become unconscious). This movement can cause:

How long the person stays unconscious may be a sign of how bad the TBI is.

Symptoms

TBI symptoms can change during recovery and are different for each person. Some symptoms may not occur right away and show up a few days or weeks later.

Symptoms of a milder TBI or concussion can include:

Mild TBIs do not always lead to loss of consciousness. Most people never pass out. They may describe seeing all white, all black, or stars. A person can also have a mild TBI and not realize it.

The following are emergency symptoms of a more severe TBI. Seek medical care right away if there are:

Head injuries that cause a TBI often occur with injury to the neck and spine. Take special care when moving people who have had a head injury.

Exams and Tests

The health care provider will perform a physical exam. The person's nervous system will be checked. There may be changes in the person's pupil size, thinking ability, coordination, and reflexes.

Tests that may be done include:

Treatment

For a mild brain injury, no treatment may be needed. But be aware that the symptoms of a brain injury can show up later.

Your providers will explain what to expect, how to manage any headaches, how to treat your other symptoms, when to return to sports, school, work, and other activities, and signs or symptoms to worry about.

Both adults and children must follow the provider's instructions about when it will be possible to return to sports.

You will likely need to stay in the hospital if:

Outlook (Prognosis)

Healing or recovering from a TBI takes time. It may take days to weeks, or even months. During that time you may:

These problems will probably recover slowly. You may want to get help from family or friends for making important decisions.

In a small number of people, symptoms of the TBI do not go away. The risk for these long-term changes in the brain is higher after more than one TBI.

Seizures may occur after more severe head injuries. You or your child may need to take anti-seizure medicines for a period of time.

More severe TBIs may result in many brain and nervous system problems.

When to Contact a Medical Professional

Contact your provider if:

Contact your provider right away if the following symptoms occur:

If symptoms do not go away or are not improving a lot after 2 or 3 weeks, contact your provider.

Prevention

Not all head injuries can be prevented. Increase safety for you and your child by following these steps:

Do not drink and drive. Do not allow yourself to be driven by someone who may have been drinking alcohol or is otherwise impaired.

Related Information

Unconsciousness - first aid
Head injury - first aid
Confusion
Decreased alertness
Concussion in adults - what to ask your doctor
Concussion in children - what to ask your doctor
Concussion in children - discharge
Concussion in adults - discharge
Preventing head injuries in children

References

Centers for Disease Control and Prevention website. Traumatic Brain Injury & Concussion. About mild TBI and concussion. https://www.cdc.gov/traumatic-brain-injury/about/index.html. Updated April 29, 2024. Accessed June 21, 2024.

Centers for Disease Control and Prevention website. Traumatic Brain Injury & Concussion. About moderate and severe TBI. www.cdc.gov/traumatic-brain-injury/about/moderate-severe-tbi.html. Updated January 22, 2024. Accessed June 21, 2024.

McClincy MP, Olgun ZD, Dede O. Orthopedics. In: Zitelli, BJ, McIntire SC, Nowalk AJ, Garrison J, eds. Zitelli and Davis' Atlas of Pediatric Physical Diagnosis. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 22.

Papa L, Goldberg SA. Head trauma. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 33.

Taylor AM, Meehan WP, Proctor MR. Sports-related traumatic brain injury (concussion). In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 729.

Trofa DP, Caldwell J-M E, Li XJ. Concussion and brain injury. In: Miller MD, Thompson SR, eds. DeLee, Drez, & Miller's Orthopaedic Sports Medicine. 5th ed. Philadelphia, PA: Elsevier; 2020:chap 126.

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Review Date: 11/2/2023  

Reviewed By: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. Editorial update 06/24/2024.

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