Definition

A concussion is a mild brain injury in which trauma to the head results in a temporary disruption of normal brain function. The injury may involve subtle pulling, tugging, or shearing of brain cells without causing any obvious structural damage. After a concussion, the brain does not work right for a while. Loss of consciousness may or may not occur, but confusion or problems with awareness or memory are usually present. Three grades of concussions were developed by the Brain Injury Association and Academy of Neurology:

  • Grade one—temporary confusion, but conscious
    • Symptoms usually clear up in less than 15 minutes.
  • Grade two—confusion and amnesia, but conscious
    • Symptoms last for more than 15 minutes.
  • Grade three—loss of consciousness for a few seconds or longer

Causes

Anything that makes the brain bounce around and against the side of the skull can cause a concussion. For example:

  • A blow or jolt to the head
  • Severe jarring or shaking
  • Abruptly coming to a stop

How a Concussion Occurs

Nucleus factsheet image
© 2009 Nucleus Medical Art, Inc.

Concussion often results from accidents that involve:

  • Motor vehicles
  • Bicycles
  • Skates, skateboards, and scooters
  • Sports and recreation
  • Falling down
  • Firearms
  • Physical violence
  • Assault and battery
  • Domestic violence
  • Child abuse

Risk Factors

These factors increase your chance of developing a concussion. Tell your doctor if you have any of these risk factors:

  • A previous concussion or head injury
  • Sex: male
  • Certain age groups:
    • Children aged five years or younger
    • Teens and young adults aged 15-24
    • Persons over 75 years old
  • Contact sports, such as football or boxing
  • Work that involves farming, logging, or construction
  • Traveling by vehicle at a high rate of speed
  • Use of alcohol
  • Lack of sleep
  • Medications that cause drowsiness

Symptoms

A concussion causes symptoms that may last for days, weeks, or even longer.

Symptoms include:

  • Confusion
  • Loss of memory about the accident
  • Low-grade headache or neck pain
  • Nausea
  • Having trouble:
    • Remembering things
    • Paying attention or concentrating
    • Organizing daily tasks
    • Making decisions and solving problems
  • Slowness in thinking, acting, speaking, or reading
  • Feeling fatigued or tired
  • Change in sleeping pattern:
    • Sleeping much longer than usual
    • Trouble sleeping
  • Loss of balance
  • Feeling light-headed or dizzy
  • Increased sensitivity to:
    • Sounds
    • Lights
    • Distractions
  • Blurred vision or eyes that tire easily
  • Loss of sense of taste or smell
  • Ringing in the ears
  • Mood changes:
    • Feeling sad, anxious, or listless
    • Becoming easily irritated or angry for little or no reason
    • Lacking motivation

Symptoms that may appear in a child with a concussion include:

  • Listlessness or tiring easily
  • Irritability or crankiness
  • Changes in:
    • Eating or sleeping patterns
    • Play
    • Behavior
    • School performance
  • Lack of interest in favorite toys or activities
  • Loss of new skills, such as toilet training
  • Loss of balance, unsteady walking

Diagnosis

The doctor will ask you and others who were present at the time of injury about your symptoms and how the injury occurred. The physical exam usually includes checking for strength, sensation, balance, reflexes, and memory.

Tests may include:

  • CT scan —a type of x-ray that uses a computer to make pictures of structures inside the head
  • MRI scan —a test that uses magnetic waves to make pictures of structures inside the head

Treatment

The goal of treatment is to allow the brain injury to heal.

Treatment may include:

  • Rest—providing adequate time for recovery
    • This means not rushing back into daily activities, such work or school.
  • Observation by a responsible adult—someone to awaken you every few hours as advised by your doctor
    • The doctor will explain how to watch for complications, such as bleeding in the brain.
  • Limiting exposure to drugs—not taking medicines without your doctor's permission
    • This is especially true for aspirin, blood thinners, and drugs that cause drowsiness. Avoid use of alcohol and illicit drugs.
  • Preventing re-injury—avoiding activities that might jolt or jar your head
    • Never return to a sports activity until your doctor has given you permission. This is generally when signs and symptoms are gone (during rest and activity) and your neurological exam is normal. Ask when it's safe to drive a car, ride a bike, work or play at heights, or use heavy equipment. Re-injury can lead to more severe or long-term symptoms. It is recommended that athletes gradually return to sports.

    If you are diagnosed as having a concussion, follow your doctor's instructions .

  • Preventing second impact syndrome—avoiding a second head injury in children and adolescents who have had a concussion
    • Even a mild second injury in children and adolescents can rapidly increase swelling, causing unconsciousness and even death. Opinions vary regarding when it is safe to return to contact sports or other activities. Talk to your child's doctor.
  • Neuropsychological testing—to determine the stage of recovery and readiness for activities, such as Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT)

Prevention

The following safety measures may help you avoid getting a concussion:

  • Don't drink and drive.
  • Avoid use of sedating drugs, especially when driving or using heavy equipment.
  • Obey speed limits and other driving laws.
  • Always use child safety seats, seatbelts, and shoulder harnesses in cars. Also learn how to safely use air bags.
  • Wear a helmet when:
    • Riding a bike or motorcycle
    • Playing a contact sport such as football, soccer, or hockey
    • Using skates, scooters, and skateboards
    • Catching, batting, or running bases in baseball or softball
    • Riding a horse
    • Skiing or snowboarding
  • Make sure your child's playing surface is soft and free of rocks, holes, and debris.
  • Reduce falling hazards at home for children and adults.
  • Wear mouth guards, face guards, pads, and other safety gear during sports.