PHTLS Kinematics of Trauma 2

Question 1

A lateral (T-bone) impact MVC places the near-side occupant at highest risk for which injury pattern?

Accepted Answer

Ipsilateral rib fractures, clavicle fracture, lateral head impact, and pelvic fractures

Answer

A lateral impact drives the door into the near-side occupant, causing ipsilateral rib, clavicle, and pelvic fractures as well as direct lateral head trauma from the window or door pillar.

Question 2

Ejection from a vehicle during a crash is significant because:

Accepted Answer

The risk of death increases approximately 300% compared to non-ejected occupants

Answer

Ejection exposes the patient to a second, uncontrolled impact with the ground or other objects, increasing the mortality risk roughly threefold compared to remaining inside the vehicle.

Question 3

A pedestrian struck by a vehicle typically experiences three phases of injury. What is the correct sequence?

Accepted Answer

Vehicle bumper impact → hood/windshield impact → ground impact

Answer

The bumper first strikes the legs or pelvis, the hood and windshield then impact the torso and head as the pedestrian is thrown up, and finally the ground impact occurs when the body falls.

Question 4

When evaluating a fall victim, which factor most reliably predicts severe injury potential?

Accepted Answer

Height of the fall

Answer

Gravitational potential energy (mgh) increases directly with height, so fall height is the primary kinematic predictor of energy transfer and injury severity.

Question 5

Primary blast injury is caused by which mechanism?

Accepted Answer

The overpressure wave passing through the body

Answer

The primary blast wave produces a rapidly changing overpressure that damages air-fluid interfaces — particularly in the lungs, ears, and bowel — without external physical contact.

PHTLS - Prehospital Trauma Life Support Practice Test

PHTLS - Prehospital Trauma Life Support Practice Test

PHTLS Kinematics of Trauma 2