Kinematics and Mechanism of Injury Flashcards

An unrestrained driver slides down and under the dashboard in a frontal collision. Which injury pattern is most expected?

Answer: Posterior hip dislocation and femur or knee fractures

The down-and-under path drives the knees into the dashboard, transmitting force up the femur to the hip.

An unrestrained driver travels up and over the steering wheel. Which finding most strongly suggests significant chest injury?

Answer: A deformed steering wheel

A bent steering wheel shows the chest absorbed major energy, raising suspicion for rib fractures, pulmonary contusion, and cardiac injury.

A restrained driver with a lap belt worn high across the abdomen is most at risk for which injury?

Answer: Lumbar flexion-distraction (Chance) fracture with bowel injury

A high lap belt acts as a fulcrum, flexing the spine over it and injuring the lumbar vertebrae and hollow viscera.

A vehicle is struck from behind at high speed. Without a properly positioned head restraint, which injury mechanism is most likely?

Answer: Cervical hyperextension followed by flexion

The torso is accelerated forward while the unsupported head lags backward, then snaps forward.

A driver-side lateral (T-bone) impact occurs. Which organ injury should be of highest suspicion in the driver?

Answer: Spleen

Driver-side impacts load the left side of the body, so the spleen, left ribs, and left pelvis are at risk.

Why is a rollover collision considered a high-risk mechanism even when occupants are restrained?

Answer: Multiple impacts in unpredictable directions cause varied injuries

Repeated impacts from multiple vectors make injury patterns unpredictable and raise the chance of spinal injury and ejection.

A patient was in a crash with airbag deployment and was wearing a seat belt. What is the best interpretation of the airbag?

Answer: It supplements the belt, and airbag-related facial, eye, and forearm injuries are still possible

Airbags are supplemental restraints and can themselves cause abrasions, eye injuries, and hand or forearm fractures.