A concussion is a minor traumatic brain injury that may occur when the head hits an object, or a moving object strikes the head.
It can affect how the brain works for a while. A concussion can lead to a bad headache, changes in alertness, or loss of consciousness.
A concussion can result from a fall, sports activities, or car accidents. A big movement of the brain (called jarring) in any direction can cause a person to lose alertness (become unconscious). How long the person stays unconscious may be a sign of the severity of the concussion.
Concussions do not always result in loss of consciousness. Most people who have a concussion never pass out. But they may describe seeing all white, black, or stars. A person can also have a concussion and not realize it.
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Symptoms of a concussion range from mild to severe. They can include:
The following are emergency symptoms of a concussion. Seek medical care right away if there are:
Head injuries that cause a concussion often occur with injury to the neck and spine. Take special care when moving people who have had a head injury.
While recovering from a concussion, the person may:
The doctor 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 ordered include:
A more serious head injury that involves bleeding or brain damage must be treated in a hospital.
For a mild head injury no treatment may be needed. But be aware that the symptoms of a head injury can show up later.
After even a mild concussion:
Recovering from a concussion takes time.
In a small group of patients, symptoms of the concussion do not go away. The risk of long-term changes in the brain is high if the person has more than one brain injury
Seizures may occur after more severe head injuries.
Call the health care provider if a head injury causes changes in alertness or produces any other worrisome symptoms.
If symptoms do not go away or are not improving after 2 or 3 weeks, talk to the doctor.
Call the doctor right away if the following symptoms occur:
Not all head injuries can be prevented. But the following simple steps can help keep you and your child safe:
Biros MH, Heegard WG. Head injury. In: Marx JA, Hockberger RS, Walls RM, et al., eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, PA: Elsevier Mosby; 2009:chap 38.
Hunt T, Asplund C. Concussion assessment and management. Clin Sports Med. 2009;5-17.
Landry GL. Head and neck injuries. In: Kliegman RM, Stanton BF, St. Geme JW III, et al., eds. Nelson Textbook of Pediatrics.19th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 680.
Updated by: Jacob L. Heller, MD, MHA, Emergency Medicine, Virginia Mason Medical Center, Seattle, Washington. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.
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