1. Kinematics of Trauma Kimberly Ann Holmes Kenney RN, CNS-Rx, MS(N), MS
CCRN, CEN, CFRN, NREMT-P

2. Objectives Discuss the laws of energy and motion.
Discuss trauma associated with blunt impact and penetrating injury.
Overview of the effects of energy distribution in MVCs.
Review the kinematics of blast and violent injuries.
Use kinematics to predict injury patterns.

3. Kinetic Energy KE = or KE = Kinetic energy is the energy of motion.
mass (weight) x velocity (speed)2 2
KE = or
mv2 2
KE =
Kinetic energy is the energy of motion.

4. Example of Kinetic Energy
The KE of a 150-lb. person traveling at 30 mph would be:
= 67,500 KE units
150 x 30 x 30 2

5. Velocity vs. Mass What is more important: velocity or mass?
150 lb. person traveling at 30 mph = 67,500 KE units
180 lb. person traveling at 30 mph = 81,000 KE units
150 lb. person traveling at 40 mph = 120,000 KE units
What is more important: velocity or mass?

6. Velocity

7. Newton’s First Law of Motion
A body at rest will stay at rest.
A body in motion will remain in motion.
Unless what?

8. Newton’s First Law and Blunt Trauma
Car strikes pole.
Driver continues moving forward.
Anterior surface of body strikes steering wheel.
Posterior body continues moving forward.
Organs compressed within body.

9. Law of Conservation of Energy
Energy cannot be created.
Energy cannot be destroyed.
But, energy can change forms and can be transferred.
Can you give an example?

10. How does the Law of Conservation of Energy pertain to trauma?
Can you give some examples?

11. Deceleration and Acceleration
Compression Injury

12. Deceleration and Acceleration
Shear Injury

13. Organ Injury
In a 50 mph MVC, what types injuries would occur if the patient were to strike the windshield?

14. Head Injury Fractures. Ligamentous injuries. Soft tissue injury.
Brain injury.
Cord damage.

15. Torso Injury Rib fractures. Heart & lung damage.
Abdominal organ damage.
Major vessel damage.

16. Extremity Injury
Fractures.
Ligamentous injury.
Soft tissue injury.

17. Types of Motor Vehicle Collisions
Frontal impact.
Lateral impact.
Rotational impact.
Rear impact.
Rollover.

18. What type of injury patterns might you see in a frontal impact?

19. Frontal Impact - Occupant Pathways
What injuries would you expect with an up and over pathway?

20. Injuries with Up & Over Pathway
continued...
Head injuries.
Spine injuries.
Chest injuries.
Fractures.
Pneumothorax.
Hemothorax.
Contusions.
Great vessel injury.

21. Injuries with Up & Over Pathway
continued...
Abdominal injuries.
Solid organs.
Hollow organs.
Diaphragm.
Fractured pelvis.

22. Frontal Impact - Occupant Pathways
What injuries would you expect with a down and under pathway?

23. Injuries with Down & Under Pathway
Posterior knee/hip dislocations.
Femur fractures.
Lower extremity fractures.
Pelvic/acetabular fractures.

24. What types of injuries would you expect?
Rear Impact
What types of injuries would you expect?

25. What types of injuries would you expect?
Lateral Impact
What types of injuries would you expect?

26. Body Motion during Lateral Impacts
Neck
Chest
Pelvis

27. What types of injuries would you expect?
Rotational Impact
What types of injuries would you expect?

28. Rollover
What injury patterns might you see following this collision?

29. Lap Restraint Device Properly positioned lap restraint.
Improperly positioned lap restraint.
What types of injuries should you anticipate?

30. Lap & Shoulder Restraint System
Shoulder harness only; lap belt not used. (Victim moves down and under).
Lap restraint only; shoulder harness not used. (Victim moves up and over)
What types of injuries should you anticipate?

31. Airbag Deployment What types of injuries would you expect to see?
What injuries would occur in a second collision?

32. Airbag Deployment What concerns would you have about a: Small patient?
Child in a car seat?

33. Motorcycle Collisions
Mandatory helmet laws have been associated with up to 300% fewer head injuries and deaths.

34. Types of Impact: Frontal/Ejection
How many impacts did this collision involve?
What types of injuries would you expect to see?

35. Types of Impact: Lateral
How many impacts did this collision involve? What types of injuries would you expect to see?

36. Pedestrian vs. Motor Vehicle
How would the injury patterns differ between the adult and the child?

37. Falls Impact surface. Height.
(Harder surface = greater injury.)
Height.
(Greater height = greater injury.)
Falls from a distance of more than three times the patient’s height produce critical injuries.

38. Falls
Deceleration injuries.
Liver.
Aorta.
Spleen.
Kidney.

39. Landing Feet First (Don Juan Syndrome)
Injuries seen in patients landing feet first:
Bilateral heel fractures.
Ankle fractures.
Distal tibia/fibula fractures.
Knee dislocations.
Femur fractures.
Hip injuries.
Spine compression fractures.

40. Landing Arms/Hands First
Physical findings:
Colles’ fractures of wrists.
Shoulder dislocations.
Fractures of the clavicles.

41. Landing Head-First Physical findings: C-spine injuries.
Facial injuries.
CNS damage.

42. Sports & Recreational Activity Mechanisms
Acceleration
Deceleration
Hyperextension
Hyperflexion
Twisting
Falling
What types of sporting or recreational injuries are common to your area?

43. Predicting Sports-Related Injuries
Kinematics & forces involved.
Equipment contributing to injury.
Involvement of protective equipment.
Nature of the sport.

44. Blast Injuries Warfare. Civilian areas. Mines. Shipyards.
Chemical plants.
Tank trucks.
Refineries.
Fireworks firms.
Silos.
LP gas tanks.
Do you have any of these in your area?

45. Blast-Related Injuries
Three mechanisms of injury:
Primary.
Secondary.
Tertiary.

46. Primary Phase Injuries
Cause: pressure wave from blast.
Affected area: gas-containing organs.
Injuries:
Pulmonary bleeding.
Pneumothorax.
Air emboli.
Perforation of the GI tract.
Burns.
Death may occur in absence of outward signs.

47. Secondary Phase Injuries
Cause: flying debris.
Affected area:
Body surface.
Skeletal system.
Injuries:
Lacerations.
Fractures.
Burns.

48. Tertiary Phase Injuries
Cause: victim thrown against an object.
Affected area: area of impact or referred energy.
Injuries: similar to those sustained in a vehicle ejection.

49. Penetrating Trauma
Physics.
Weapon velocity.
Bullet design.

50. Penetrating Trauma Newton’s First Law and ballistics:
Bullet in brass cartridge is at rest.
Bullet propelled by rapid combustion of powder.
Bullet leaves barrel of gun.
Bullet strikes a body.
Bullet transfers energy to victim.

51. Low-Energy Injuries Low velocity. Usually hand-driven weapons.
Less secondary trauma.
Multiple wounds from a single weapon.

52. Low-Energy Penetrating Wounds
How does the length of the weapon relate to the cone of damage?

53. Assessment of Low-Energy Injuries
Type of weapon involved.
Path of weapon.
Depth of penetration.
Number of wounds.
Underlying anatomy.

54. Medium-Energy Penetrating Injuries

55. High-Energy Penetrating Injuries
How do these weapons differ from handguns and shotguns?
How do the wounds differ internally and externally?

56. Projectile - Frontal Area
The larger the frontal area of the projectile, the greater the damage.
The larger the cavitation and the greater the damage, the greater the exit wound.

57. Gunshot Wounds - Cavitation
Reformation by elastic tissue
Temporary
cavity
Direction of travel
Bullet
Permanent
cavity
Compression
and crush

58. Gunshot Wounds Describe the difference between
entrance and exit wounds.

59. Tumbling Projectiles Some projectiles are designed to tumble.
Tumbling creates greater tissue damage and more tissue destruction.

60. Fragmentation
The shotgun round is the ultimate in fragmentation.

61. Considerations for Penetrating Trauma
Scene safety.
Patient care is the priority!
Weapon type.
Range at which weapon was fired.
Number of entrance and exit wounds.
Underlying anatomy and track.
Crime scene preservation.

62. Kinematics Summary
The cornerstone of assessment is early consideration of kinematics to predict hidden injury.