1. Mechanisms of Injury
MASTER
© BASICS Education March 2019

2. Read the wreckage Mentally reconstruct the mechanism(s) of injury i.e.
Vectors
Relative masses
Restraints
Safety systems

3. Sources of Information
Scene
Casualty
Injuries
Witnesses
Wreckage

4. Kinetic Energy
Transfer of energy through body tissue leads to damage to that tissue
The amount of energy available (Kinetic energy) to cause injury is a factor of mass and velocity (speed)
Kinetic Energy = ½Mass x Velocity2
Hence speed has a greater impact on Kinetic energy that mass

5. Energy transfer

6. The 3 impacts 1st impact The vehicle with the object
2nd impact The occupant with the inside of the vehicle
3rd impact The internal organs with each other and the body skeleton

7. RTCs Frontal Side impact Roll over Rear end shunt
Each produce a different pattern of injury

8. Large & small vehicles No crumple zones Lower limb injuries
? Seatbelts
Impact with
Petrol tank - # pelvis
Handlebars - # femurs
Other vehicles
Road - friction burns

9. Pedestrians and pedal cyclists
Adults tend to turn away to protect themselves resulting in more posterior impacts
Children tend to turn to face the oncoming vehicle
A history from witnesses is useful to assess the extent of the impact.

10. Falls from heights
Fall from more than twice the height of the casualty causes serious injury
Injuries dependent on
Type of surface fallen onto
Posture of the casualty at time of impact
Part of body impacting first

11. Penetrating trauma Stab wounds Gunshot wounds Bullet Shotgun pellets
Other objects
If object still imbedded in patient, do not remove

12. Firearms
Compression, separation and cavitation of the tissues along the tract of the object
Permanent and temporary cavities formed
Damage depends on the amount of energy transferred
Other factors: path / yaw / fragmentation / tumble

13. Blast & fragmentation injury
Primary
Blast wave injuries
Flash burns
Secondary
Fragmentation injuries
Tertiary
Blunt trauma
Structural collapse
Quaternary
Other injuries not related to the above mechanisms e.g. crush syndrome, flash burns

14. Mechanisms of injury
Questions?

15. Summary Read the wreckage Think about energy transfer
Maintain high index of suspicion
Communicate all relevant information

16. Carnival UK Immediate Care Course