Concussion 

Concussion is the sudden but short-lived loss of mental function that occurs after a blow or other injury to the head. The medical term for concussion is minor traumatic brain injury. Symptoms of concussion include:

• brief loss of consciousness
• memory loss
• disturbances in vision, such as 'seeing stars'
• confusion

How common is concussion?

Concussion is the most common but least serious type of brain injury. It is estimated that one in every 2,000 people will experience an episode of concussion requiring hospital treatment each year in England.

However, the actual figure could be much higher, as many people do not seek treatment for concussion. Researchers from the World Health Organization estimated that the true number of people affected by concussion each year could be as high as one in 165.

At-risk groups

Most cases of concussion occur in children and teenagers aged five to 14, with the two most common causes being sporting and cycling accidents.

Falls and motor vehicle accidents are a more common cause of concussion in older adults.

People who regularly play competitive team sports such as football and rugby have a higher risk of concussion.

Recovery

Most people with concussion do not require any treatment as they normally get better by themselves.

However, they will require a period of careful monitoring, ranging from several days to several weeks, depending on the severity of the concussion.

This is because what are assumed to be the symptoms of concussion could in fact be the symptoms of a more serious condition, such as bleeding that develops between the skull and the brain (subdural haematoma) or onto the surface of the brain (subarachnoid haemorrhage), both of which are medical emergencies.

See Concussion – Symptoms for more information about possible danger signs that could mean a more serious brain injury has occurred.

Outlook

The outlook for most cases of concussion is very good. While the medical term "minor traumatic brain injury" can sound serious, the actual extent of damage to the brain is usually minimal and does not usually cause any long-term problems or complications.

There is evidence that repeated episodes of concussion could cause long-term problems with mental abilities and trigger the onset of dementia. This type of dementia is known as chronic traumatic encephalopathy (CTE).

However, this seems to only be a significant risk for professional athletes who experience repeated episodes of severe concussion, such as boxers (CTE is sometime nicknamed "boxer’s brain".)