If a passenger strikes his or her head on the windshield during a motor-vehicle crash, which statement is MOST accurate about brain injury patterns?

• A. The posterior portion of the brain will receive the initial impact, resulting in severe intracerebral hemorrhage.
• B. You will always see a starburst fracture of the windshield at the location where the patient struck his or her head.
• C. He or she will likely experience a hyperflexion injury, resulting in fractures of the cervical spine.
• D. The anterior part of the brain sustains a compression injury, while the posterior part sustains a stretching injury.

Answer: (D)

When the head is suddenly decelerated by striking the windshield, the brain is propelled forward inside the skull and then lags as the skull stops. This creates a coup-contrecoup injury pattern: tissue at the site of impact is compressed against the skull, while the opposite side is stretched. In a windshield impact, the front (anterior) part of the brain is pressed against the inner skull, producing compression injuries, and the back (posterior) part is pulled and stretched, leading to stretching injuries. This combination best explains the brain injury pattern in this scenario, including possible contusions at the site of impact and diffuse axonal or other injuries on the opposite side.

The other statements don’t fit as well. The initial impact is not typically described as a posterior brain event, windshield fracture patterns aren’t universal or diagnostic of brain injuries, and a hyperflexion pattern with cervical spine fractures isn’t the characteristic brain injury pattern for a head struck on the windshield.