Mechanisms of Injury

Mechanical Injury

A force placed on part of the body resulting in the changing of the function or structure.

Compression

A force that, with enough energy, crushes tissue.

Tension

A force that pulls or stretches the tissue.

Bending

Compression and tension forces applied together upon a structure.

Shearing

A force that moves parallel with the tissue.

Blister

A collection of fluid below or within the top layer of skin.

Bruise

Bleeding under the skin.

Puncture

Penetration by a sharp object.

Avulsion

Tissue is ripped from its source.

Abrasion

Surface layer of skin is scraped off.

Laceration

A jagged cut.

Incision

A straight/sharp cut.

Muscle Strains

All strains and sprains are graded on a 3-tier scale.

Grade 1 Strain

Mild strain with local pain and little bruising, little to no loss of strength or motion.

Grade 2 Strain

Moderate strain with moderate pain, bruising, swelling, and impaired muscle function.

Grade 3 Strain

Severe strain with loss of muscle function and palpable defect.

Cramp

A painful involuntary contraction of a skeletal muscle or muscle group.

Spasm

Reflex reaction caused by trauma.

Acute Onset Muscle Soreness

Occurs right away after exercise.

Delayed Onset Muscle Soreness (DOMS)

Occurs 48-72 hours after exercise, caused by microtears in the muscle.

Chronic Muscle Injuries

Long-term injuries caused by the wearing away of a structure or repeated acute injuries.

Tendons

Joins a muscle to bone and are actually 2x the strength of the muscle they serve (strain)

Ligaments

Joins a bone to bone and usually tear at the ends. (sprain)

Cartilage

The shock absorber between two bones.

Fractures

Types of injuries related to bones.

Dislocation (joint)

An injury where bones are forced out of their normal position.

Subluxation (joint)

A partial dislocation of a joint.

Fractures

(bone)

contusion

bruising of the muscle

muscle

Soreness, strains (degrees 1-3)

Ligaments

Sprains (degrees 1-3)