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 must be impact to cause either the coup or contrecoup injuries. In the absence of impact (if only an acceleration, deceleration, or rotational force), no contrecoup injury is seen.
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
The patient suffered a coup-contrecoup injury as a result of hitting her head on the steering wheel during the crash.