A concussion is a common head injury, also known as a mild Traumatic Brain Injury (MTBI). It is an injury that results from a direct blow to the head, face or jaw causing an alteration of brain function which can become evident through a variety of related symptoms. The damage to the brain during a concussion is caused by a sudden shifting of the brain inside the skull. This shifting can cause the brain to knock against the hard bone of the skull, causing most of the damage to brain cells. A blow to the head can also cause a rotational injury to the brain which can cause shearing of the brain nervous fibres.

Concussions are hard to recognize as there is no visible injury to the structure of the brain. Recognition comes from various post-concussion symptoms such as; memory loss, difficulty concentrating, dizziness, fatigue, headaches and many others. Concussions are dangerous because an individual can feel normal while in fact still have a concussion and think that they are OK to return to activity. This can be bad because returning to activity before the brain has fully healed leaves the individual more likely to suffer a second concussion, known as second impact syndrome.

A second blow to the head, even if it is a minor one, can result in a loss of control of the brain’s blood supply.  Loss of control of blood supply leads to swelling of the brain resulting in increased pressure inside the skull, which can lead to herniation of the brain.  The average time from second impact to brainstem failure is quite rapid, taking only two to five minutes.  After this occurs, the situation becomes very severe and can become fatal.

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