Physical Agents Flashcards
Thermal physical agents:
- ultrasound
- hot pack
- ice pack
- diathermy
Mechanical physical agents:
- mechanical traction
- elastic bandage/stockings
- whirlpool
- ultrasound
electromagnetic physical agents
- ultraviolet
- laser
- TENs
absolute contraindications of general physical agent use:
- pregnancy
- malignancy
- pacemaker
- impaired sensation
- impaired mentation
general effects of physical agents:
- changes rates of circulation (chemical reactions)
- alter fluid flow
- alter cell function
- increase membrane permeability and transport
- helps move more quickly through inflammation stage
- increases enzyme activity rate
- promotes collagen deposition
purpose of inflammation:
- dilute/dissolve cells or agents
- can be harmful if directed at wrong tissue or overly exuberant
cardinal signs of inflammation
- heat (increased vascularity)
- redness (increased vascularity)
- swelling (blockage of lymphatic drainage)
- pain (pressure, chemical irritation, pain sensitive structures)
- loss of function (pain and swelling)
vascular response to inflammation
- transient constriction (NE-injured)
- non-injured vasodilation
- increased permeability (edema)
- changed physical attraction between vessel walls
- in vasoconstriction and increased permeability: slowing of flow and increased viscosity
- extravasation
- transudate (serum once outside the cell)
- exudate
- pus
cellular reaction to inflammation:
- platelets: (RBC losts outside in exudate, severe injury)
- neutrophils (WBC activated for chemotaxis and phagocytosis, 0-24 hrs)
- monocytes/macrophages (most important; vessel to interstitial)
- lymphocytes (immune response via antibodies in chronic inflammation)
- basophils (release histamine)
parts of proliferation phase
-epithelialization
-wound contraction
-neovascularization
fibroplasia
maturation phase
-balance of collagen synthesis and lysis (collagen conversion)
stages of scar formation
Stage 1: deposition of type III collagen; scar prone to rupture
Stage II: increased fibroplasias; covnersion type III to type I collagen; wond contraction begins, remodeling at peak
Stage III: scar consolidation; remodeling decreases
Stage IV: remodeling beginning to cease; least responsive to intervention
what stage of scar formation has the greatest responsiveness to intervention?
Stage II
old definition of pain:
unpleasant sensation to warn of tissue injury and with an emotional response
new definition of pain:
: conscious correlate of the implicit perception that tissue is in danger, where the quality and intensity of the pain depend on the degree of perceived threat
a-delta nerve fibers:
- fastest conducting, first component of pain, leads to reflexive withdrawal
- myelinated
- short duration
- sense mechanical and thermal sensations
- sharp, pricking, temp. changes
c fibers:
(polymodal nociceptors) slow conducting; second component of pain -non myelinated -long duration -dull, ache, burning sensation -not well tolerated
what type is the majority of nociceptors?
c fibers
80%
primary afferent neurons:
a delta fibers
c fibers
a-beta fibers
a-beta fibers
transmit non painful sensations related to vibration, stretching, mechanoreception, abnormal pain
- skin, bones, joints
- large myelinated axons
- conduct faster than a delta or c fibers
opiopeptin system of pain modulation with external opioids:
\:inhibitory action by binding to opioid receptors in the brain and peripherally -presynaptic: prevent influx of Ca -postsynaptic: activate outflux of K -activates endogenous opioids -
naloxone:
antagonist to opiates
-higher affinity for opioid receptors
endogenous opiates
- stimulated by noxious, stressful sensory inputs
- bind to same opioid receptors
what modality stimulates edogenous opiates:
- e stim, burst or low rate modes
- acupuncture and painful stimulation
pain-spasm-pain cycle
-reflex
-nociceptor activation results in T-cell activation
-stimulates anterior horn cell to cause a muscle fiber to contract
-results in accumulation of fluid and tissue irritants and mechanicl compression of noviceptor
=increasing nociceptor activation
acute pain:
- sharp, localized, rapid onset, short duration
- appropriate response normally for pathoanatomical pain
referred pain
-occurs at site remote from source of
disease/injury
-no dorsal horn neurons (second order) dedicated to visceral; converge on somatic nociceptor 2nd order neuron
theories of referred pain:
- from a nerve to its innervation
- from one area to another derived from same dermatome
- from one area to another derived from the same embryonic segment
- converge on the same or similar areas of the spinal cord and synapse with the same 2nd order neuron
how do you differentiate between pain from visceral origin and musculoskeletal pain?
- MSK pain vaires with movement
- MSK pain varies with physical stress of tissue
persistent pain
- nociceptors are continually firing as long as a stimulus is present (can lead to persistent)
- episodic
- recurrent
- predisposing factors: poor physical condition, body mechanics, posture, etc.)
neuropathic pain
(disfunctional) -somatic nerves: intraneural extraneural associated with history of injury -SNS nerves: complex regional pain syndrome (CRPS)
examples of neuropathic pain from somatic nerves:
- radiculopathy
- sciatica
- phantom pain
chronic pain
(dysfunctional)
- dull diffuse, poorly localized
- slow gradual onset (3-6 months)
- unknown cause
- inconsistent behaviors
- fear avoidance
A high specific heat…
- requires more energy to heat up
- holds more energy at a given temp.
- more caution-have to apply at a lower temperature
highest to lowest specific heat of materials:
water skin muscle body as whole fat bone air
the greater the thermal conductivity=
faster transfer
ice has a ____ thermal conductivity than water
higher
- takes a lot of energy to convert ice to water
- ice causes more rapid cooling than water
the rate of temperature rise _____ in proportion to tissue thickness
decreases
convection
- contact with circulating medium (whirlpool; fluidotherapy)
- thermal agent is in motion
- transfer more heat in same period of time
