Traumatic brain injury
Concussion; Brain injury - concussion; Traumatic brain injury - concussion; Closed head injury - concussionA 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:
- Mild TBI, also called a concussion
- Moderate TBI
- Severe 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.
Loss of consciousness
Unconsciousness is when a person is unable to respond to people and activities. Doctors often call this a coma or being in a comatose state. Other c...
Read Article Now Book Mark ArticleCauses
TBIs can be caused by:
- Falls
- Sports injuries
- Vehicular accidents
- Assaults
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:
- The brain to bounce or twist around in the skull
- Chemical changes in the brain
- Damage to brain cells
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:
- Acting somewhat confused, feeling unable to concentrate, or not thinking clearly
- Being drowsy, hard to wake up, or similar changes
- Headache
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Loss of consciousness for a fairly short period of time
Loss of consciousness
Decreased alertness is a state of reduced awareness and is often a serious condition. A coma is the most severe state of decreased alertness from whi...
Read Article Now Book Mark Article - Memory loss (amnesia) of events before the injury or right after
Amnesia
Memory loss is unusual forgetfulness. You may not be able to remember new events, recall one or more memories of the past, or both. The memory loss ...
Read Article Now Book Mark Article - Nausea and vomiting
- Seeing flashing lights, light sensitivity
- Feeling like you have "lost time"
- Sleep abnormalities
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:
- Changes in alertness and consciousness
- Confusion that does not go away
- Seizures
- Muscle weakness on one or both sides of the body
- Pupils of the eyes that are not equal in size
- Symptoms in just one eye
- Unusual eye movements
- Repeated vomiting
- Walking or balance problems
- Unconsciousness for a longer period of time or that continues (coma)
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.
Head injury
A head injury is any trauma to the scalp, skull, or brain. Head injury can be either closed or open (penetrating). A closed head injury means you rec...
Read Article Now Book Mark ArticleExams 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:
- Blood and urine tests
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EEG (brain wave test) may be needed if seizures continue
EEG
An electroencephalogram (EEG) is a test to measure the electrical activity of the brain.
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Head CT (computerized tomography) scan
Head CT
A head computed tomography (CT) scan uses many x-rays to create pictures of the head, including the skull, brain, eye sockets, and sinuses.
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MRI of the brain (magnetic resonance imaging) of the brain
MRI of the brain
A head MRI (magnetic resonance imaging) is an imaging test that uses powerful magnets and radio waves to create pictures of the brain and surrounding...
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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.
- Children will need to be watched and make activity changes.
Watched and make activity changes
Your child was treated for a concussion. This is a mild brain injury that can result when their head hits an object or a moving object strikes the h...
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Adults also need close observation and activity changes.
Adults also need close observation and ...
A concussion may occur when the head hits an object, or a moving object strikes the head. A concussion is usually a minor or less severe type of bra...
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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:
- Emergency or more severe symptoms of head injury are present
- There is a skull fracture
- There is any bleeding under your skull or in your brain
Outlook (Prognosis)
Healing or recovering from a TBI takes time. It may take days to weeks, or even months. During that time you may:
- Be withdrawn, easily upset, or confused, or have other mood changes
- Have a hard time with tasks that require memory or concentration
- Have mild headaches
- Be less tolerant of noise
- Be very tired
- Feel dizzy
- Have blurry vision at times
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:
- A head injury causes changes in alertness.
Head injury
A head injury is any trauma to the scalp, skull, or brain. Head injury can be either closed or open (penetrating). A closed head injury means you rec...
Read Article Now Book Mark Article - A person has other worrisome symptoms.
- Symptoms do not go away or are not improving after 2 or 3 weeks.
Contact your provider right away if the following symptoms occur:
- Increased sleepiness or difficulty waking up
- Stiff neck
- Changes in behavior or unusual behavior
- Changes in speech (slurred, difficult to understand, does not make sense)
- Confusion or problems thinking straight
- Double vision or blurred vision
- Fever
- Fluid or blood leaking from the nose or ears
- Headache that is getting worse, lasts a long time, or does not get better with over-the-counter pain relievers
- Problems walking or talking
- Seizures (jerking of the arms or legs without control)
- Vomiting more than 3 times
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:
- Always use safety equipment during activities that could cause a head injury. These include seat belts, bicycle or motorcycle helmets, and hard hats.
- Always use child safety seats in a car.
Child safety seats
All states require children to be secured in a car seat or booster seat until they reach certain height or weight requirements. This article gives y...
Read Article Now Book Mark Article - Learn and follow bicycle safety recommendations.
Bicycle safety recommendations
Many cities and states have bike lanes and laws that protect bicycle riders. But riders are still at risk of being hit by cars. Therefore, you need...
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Do not drink and drive. Do not allow yourself to be driven by someone who may have been drinking alcohol or is otherwise impaired.
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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Brain - illustration
The major areas of the brain have one or more specific functions.
Brain
illustration
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Concussion - illustration
A concussion may result when the head strikes against an object or is struck by an object. Sometimes a concussion may cause a brain contusion (bruise). Concussions may produce unconsciousness or bleeding in or around the brain.
Concussion
illustration
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Brain - illustration
The major areas of the brain have one or more specific functions.
Brain
illustration
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Concussion - illustration
A concussion may result when the head strikes against an object or is struck by an object. Sometimes a concussion may cause a brain contusion (bruise). Concussions may produce unconsciousness or bleeding in or around the brain.
Concussion
illustration
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.