In a traumatic brain injury, which injury is described as occurring directly beneath the point of impact?

• A. Coup injury
• B. Contrecoup injury
• C. Subdural hematoma
• D. Diffuse axonal injury

Answer: (A)

Direct injury at the point of contact is called coup injury. The brain is pressed into the skull where the blow lands, producing a localized contusion right beneath the impact site. In contrast, contrecoup injury happens on the opposite side as the brain rebounds after the initial impact. A subdural hematoma is a bleed between the dura and arachnoid caused by tearing of bridging veins, typically from acceleration–deceleration, and isn’t defined by being directly under the impact. Diffuse axonal injury involves widespread tearing of axons due to rapid movement of the brain within the skull, leading to diffuse dysfunction rather than a focal lesion at the impact site.