Concussion Health Article

Definition

A concussion is a brain injury that may result in a bad headache. altered levels of alertness, or unconsciousness.

See also: Concussion - first aid

Causes, incidence, and risk factors

There are more than a million cases of concussion each year in the United States.

A concussion may result when the head hits an object or a moving object strikes the head. A concussion can result from a fall, sports activities, and car accidents. Significant movement of the brain (jarring) in any direction can cause unconsciousness. How long a person remains unconscious may indicate the severity of the concussion.

Often victims have no memory of events preceding the injury, or immediately after regaining consciousness. More severe head injuries can cause longer periods of memory loss (amnesia).

Usually, a person has the most memory loss immediately after getting hurt. Some of the memory comes back as time goes by. However, complete memory recovery for the event may not occur.

Bleeding into or around the brain can occur with any blow to the head, whether or not unconsciousness occurs. If someone has received a blow to the head, they should be watched closely for signs of possible brain damage.

Things to watch for include repeated vomiting, unequal pupils, confused mental state or varying levels of consciousness, seizure-like activity, weakness on one side of the body, or the inability to wake up (coma). If any of these signs are present, immediately call 911.

Symptoms

A concussion results from a significant blow to the head. Symptoms can range from mild to severe. They can include:

• Headache
• Altered level of consciousness (drowsy, hard to arouse, or similar changes)
• Loss of consciousness
• Memory loss (amnesia) of events surrounding the injury

Emergency signs:

• Changes in alertness and consciousness
• Convulsions
• Muscle weakness on one or both sides
• Persistent confusion
• Persistent unconsciousness (coma)
• Repeated vomiting
• Unequal pupils
• Unusual eye movements
• Walking problems

Head injuries which result in concussion often are associated with injury to the neck and spine. Take particular care when moving patients who have had a head injury.

Signs and tests

A neurological examination may show abnormalities.

Tests that may be performed include:

• Head CT
• MRI of the head