What is Mechanism of Injury (MOI)?

First aiders should be aware of how to assess a mechanism of injury (MOI). Mechanism of injury describes how energy of motion is transferred to an individual resulting in injury.Road traffic accident

A classic example is the motor vehicle crash (MVC) in which the extent of damage to the vehicle can be directly related to the extent of injuries the patient may have.

A car crash might be a minor “fender bender” with no damage to the vehicle and no injury to the occupant, or it might be a front-end collision with significant vehicle damage and potentially serious injury to the occupant’s head, chest, neck, and abdomen.

Falls are another example of how determining the mechanism of injury can be used to estimate the extent of damage to the patient.

The height of the patient’s fall, the position in which the patient landed, and the number and kind of objects the patient struck provide valuable information about the patient’s potential condition. For example, a patient who has fallen on an outstretched hand may have a shoulder injury as well as a wrist injury.

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John Furst

JOHN FURST is an experienced emergency medical technician and qualified first aid and CPR instructor. John is passionate about first aid and believes everyone should have the skills and confidence to take action in an emergency situation.

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