Coup Contrecoup Brain Injuries

Definition: A coup countercoup (pronounced coo contra coo) brain injury is an injury that occurs both at the site of trauma and the opposite side of the brain. A "coup" injury is the initial site of impact. For example, if you were in a car accident and struck your head on the steering wheel, you might have a "coup" brain injury near the location of the forehead.

A contrecoup injury happens at the opposite side of the site of injury, so if you struck your forehead, the brain injury would be at the back of the brain. This happens because the brain is the consistency of firm pudding, and does move within the skull. The initial impact on the forehead causes the first injury, but the movement of the brain within the skull causes the second impact against the back of the skull.

Imagine shaking ice cubes in a glass.  If you shake the glass hard enough, you can make the ice cubes hit both sides of the glass with one sharp movement of your hand.  The glass impacts the first side of the glass hard enough to bounce and hit the opposite side of the glass.  The same is true of the brain during a traumatic injury, the brain is the ice cubes, the skull is the glass. 

Together, these injuries are called a coup contrecoup injury, indicating that both injuries are present.

There does not have to be an impact to cause either the coup or contrecoup injuries. Shaken babies, for example, can have these injuries even if the head is never struck by another object. The movement of the brain within the skull is enough to cause the injuries.

Pronunciation: Coo con-truh coo

Also Known As: coup, contrecoup, traumatic brain injury,

Common Misspellings: coo contracoo, contracoup, coo injury, coop injury, contracoop, contracoo, contrecoo, conracoo brain injury,

Examples: Not only did the patient have whiplash, the crash also caused a coup contrecoup injury to her brain.