Injury Response

• goal

• injury type

• timeline (how recent)

considerations when choosing a therapeutic intervention/modality

• inactive phase (shut down)

• active phase

• resistive phase

• aggressive phase

rehabilitation phases

rehabilitation phase

rehabilitation phases where therapeutic modalities should be used for pain, spasm, and edema relief

active phase

rehabilitation phase for joint mobilization, soft tissue mobilization, ROM, and flexibility

resistive phase

rehabilitation phase for muscle strength and endurance exercises, proprioception and balance exercises for neuromuscular recovery

aggressive phase

rehabilitation phase for plyometric exercises, functional exercises, and performance-specific exercises for return to function

• active phase

• resistive phase

• aggressive phase

rehabilitation phases that focus on therapeutic exercises

healing phases

• inflammation

• proliferation (early and late)

• remodeling/maturation

stress

mechanical, thermal, emotional, or chemical force on the body

cell death

tissue response when physical stress level is none to low

decreased tolerance (atrophy)

tissue response when physical stress level is low

maintenance

tissue response when physical stress level is normal

increased tolerance (hypertrophy)

tissue response when physical stress level is moderate (positive overload)

injury

tissue response when physical stress level is high (chronic)

cell death

tissue response when physical stress level is extreme (acute, ex ACL)

• alarm

• resistance

• exhaustion

general adaption syndrome stages

our stress response system defends, then fatigues

general adaption syndrome (GAS)

GAS Alarm stage physiology changes

• fight or flight

• increased HR

• increased CO

• increased SV

• vasoconstriction

• cortisol

GAS resistance phase

• longest phase

• adapts to stressor

intensity, duration

stress applied to body must be of proper ________ and __________

Wolff’s Law

bones adapts to the forces placed on it

osteoblast

builds bone

osteoclasts

absorb and remove unwanted bone

• skin

• intestinal tract

• blood

labile cell tissue locations

good

labile cell ability to regenerate

bone

stabile cells tissue location

some

stabile cells ability to regenerate

• muscle

• PNS

• CNS

permanent cells tissue locations

some

permanent cells located in muscle regenerative ability

some

permanent cells located in PNS regenerative ability

none

permanent cells located in CNS regenerative ability

• skin

• heart

• blood vessels

• hollow organs

• glands

• external openings

structures lined by epithelial tissue

stratum corneum

forms the skin’s outer later

keratin

what is the stratum corneum filled with?

• skeletal

• smooth

• cardiac

muscle types

• Type I

• Type II

muscle fiber types

Type I - smaller diameter

muscle fiber type that is recruited faster

Type I

muscle fiber type slow to fatigue and prevalent in postural muscles

Type II

muscle fiber type capable of generating a high amount of force in a short time

• brain

• spinal cord

structures that make up CNS

peripheral nerves

structures that make up PNS

afferent signal

signal that travels away from the stimulus to the brain

efferent signal

signal that goes towards the stimulus

• Ia (A-alpha)

• Ib (A-alpha)

• II (A-beta)

• III (A-delta)

• IV (C)

afferent axons

efferent axons

• A-alpha

• A-gamma

• A-beta

muscle spindle afferent

Ia (A-alpha) axon function

golgi tendon afferent

Ib (A-alpha) axon function

touch/pressure afferent, secondary muscle afferent

II (A-beta) axon function

temperature afferent, sharp pain

III (A-delta) axon function

• temperature afferent

• dull pain

IV (C) axon function

skeletal muscle efferent

A-alpha axon function

muscle spindle efferent

A-gamma axon function

muscle and muscle spindle efferent

A-beta axon function

motor nerves

acetylcholine location

transmits motor impulse

acetylcholine functions

CNS

calcitonin gene-related peptide location

calcitonin gene-related peptide functions

• vasodilation

• activates leukocytes

• reduces pain threshold

brain stem

dopamine location

dopamine absence consequences

• motor dysfunction

• increased BP

• increased CO

• vasoconstriction

brain stem

epinephrine location

• behavior

• bronchial dilation

• emotions

• mood

• vasoconstriction

epinephrine affects:

autonomic nervous system

norepinephrine location

• arousal

• dreams

• mood regulation

• vasoconstriction

norepinephrine functions

platelets, mast cells

serotonin location

• sensory perception

• sleep

• temperature regulation

• vasoconstriction

serotonin functions

pain-transmitting nerve fibers

substance P location

transmits noxious impulses, produces inflammation-like responses in local tissues

substance P function

primary destruction

tissue destruction as a result of force or stress

secondary destruction

cell death or destruction as a result of primary injury

platelet accumulation, coagulation, leukocyte migration

what happens during the acute phase of healing?

• fibroblastic repair

• tissue growth

• collagen matrix formation

what happens during the proliferation phase of healing?

more new tissue deposited, get tissue back to original function

what happens during the maturation/remodeling phase of healing?

neutrophils and macrophages

phagocytes and fibroblasts released during acute inflammation

• phagocytes and fibroblasts released

• formulation of granulation of tissue

• hemorrhage

• fibrin clot formation

• histamine released

acute inflammatory response

increase cell permeability → increased swelling

histamine’s effect on traumatized cells

2-4 days post injury

acute inflammatory response duration

• redness

• swelling

• tenderness

• increased temperature

• loss of function

cardinal signs of inflammation

• acute

• subacute

• chronic

stages of inflammation

0-14 days

acute inflammation duration (acute vs subacute vs chronic)

14-31 days

subacute inflammation duration (acute vs subacute vs chronic)

>31 days after expected resolution

chronic inflammation timeline

• heparin

• histamine

• kinins

• neutrophils

• prostaglandins

• serotonin

• leukotrienes

inflammatory mediators

• heparin

• histamine

• kinins

• prostaglandins

• leukotrienes

pro-inflammatory inflammation mediators

• neutrophils

• serotonin

anti-inflammatory inflammation mediators

heparin

inflammatory mediator that inhibits coagulation by preventing the conversion of prothrombin to thrombin

histamine

inflammatory mediator that vasodilates arterioles and increases vascular permeability

kinins

inflammatory mediator that dilates arterioles and produce pain

neutrophils

inflammatory mediator that destroys bacteria but also attacks healthy cells

prostaglandins

inflammatory mediator that vasodilates and increases vascular permeability

serotonin

inflammatory mediator that promotes vasoconstriction

leukotrienes

inflammatory mediator that causes smooth muscle contraction, increases vascular permeability, and attracts neutrophils

removing debris and temporarily repairing tissue

goals of proliferation phase

72 hours post injury to 3 weeks

proliferation phase duration

resolution, regeneration, repair

types of tissue repair during the proliferation phase

• finish cleaning up the area

• increase strength of the repaired or replaced tissues

goals of maturation/remodeling phase

Type III

type of collagen placed in tissue regeneration of proliferation phase

Type I

collagen type placed during maturation/remodeling phase to replace Type III fibers

keys to success in maturation/remodeling phase

• rehab

• appropriate stress

• eccentric and concentric exercises

• metaplasia

• dysplasia

• hyperplasia

• atrophy

• hypertrophy

soft tissue adaptations

metaplasia

conversion of one kind of tissue to another (ex myositis ossification)