SECTION FIVE
TRAUMA
Chapter 23
Kinematics of Trauma
• Describe the three collisions associated with motor vehicle
crashes.
• Relate how the fundamental principles of physics apply to motor
vehicle crashes and other types of incidents.
• State Newton’s three laws.
Kinematics of Trauma
• Injuries are the leading cause of death among children and young
adults.
• Kinematics introduce the basic physical concepts that dictate
how injuries occur and affect the human body.
Energy and Trauma
• Work
– Force acting over distance
• Kinetic energy
– Energy of moving object (KE = ½mv2 )
• Potential energy
– Product of weight, gravity, and height
Vehicular Collisions
• Three types of crashes
– Collision of car against another car or object
– Collision of passenger(s) against interior of car
– Collision of passenger’s internal organs against the solid structures of
the body
Significant Mechanisms of Injury (MOI)
• Severe deformities of the frontal part of a vehicle with or without
intrusion to passenger compartment
• Moderate intrusion from a T-bone accident
• Severe damage from the rear
• Collisions in which rotation is involved
Frontal Collisions
• Evaluate seat belts and airbags.
• Remember that supplemental restraint systems can cause injury.
• Check for contact points in dash, instrument panel, and
windows.
• Steering wheels can also cause chest injuries, especially if no air
bag is present.
Rear-End Collisions
• Commonly causes whiplash injuries
• In unrestrained passengers, the body will be thrust forward into
the dashboard and windshield.
• Back seat passengers wearing only lap belts are prone to lumbar
and thoracic spine injury.
Lateral Collisions
• Highest incident of deaths
• Body is less tolerant of lateral bending.
• Intrusion of a vehicle into the passenger compartment can
indicate injuries to the ribs and lower extremities.
• 25% of severe injuries to the aorta are a result of lateral
collisions.
Rollover Crashes
• Injury patterns differ if patients are unrestrained.
• The most unpredictable injuries are from unrestrained
passengers.
• Ejection is the most common life-threatening injury.
Falls
• Injury potential is related to the height from which the fall
occurs.
• A fall three times the person’s height is considered significant.
• Patients landing on their feet may have less internal injuries but
leg and spine injuries are likely.
Considerations for Falls
• The height of the fall
• The surface struck
• The part of the body that hit first, followed by the path of energy
displacement
Penetrating Trauma
• Second largest cause of death after blunt trauma
• Low-energy penetrating trauma results from impaled objects.
• Medium and high energy penetrating trauma can cause
cavitation.
• Determining the entrance and exit wound can help determine
internal pathway.
Newton’s Laws
• Objects at rest tend to stay at rest and objects in motions stay in
motion, unless acted upon by some force.
• Force equals mass times acceleration.
• F=M x A
• For every action, there is an equal and opposite reaction.