Physical Agents Midterm Review Flashcards
What do physical agents do?
Modify tissue inflammation and healing
Relieve pain
Alter collagen extensibility
Modify muscle tone/contracting ability
deep heating thermal agents
ultrasound and diathermy
superficial heating thermal agents
hot pack and paraffin
superficial cooling agents
cold pack, ice massage
mechanical agents
mechanical traction
compression (bandage, stockings)
water (whirlpool)
sound (ultrasound)
electromagnetic fields
ultraviolet, laser
electrical currents
TENS/IFC NMES/Russian High Volt Iontophoresis EMG
steps in choosing a modality
goals and effects of treatment
contraindications and precautions
evidence for physical agent use
cost, convenience and availability
characteristics of A-delta fibers
respond to intense mechanical stimulation and heat or cold
–short duration, sharp, stabbing, or pricking sensation
–small and myelinated
–4-30 m/s
–20% of pain afferents
–not blocked by opioids
characteristics of C afferent fibers
longer duration, dull, throbbing, aching, burning, tingling, diffusely localized, accompanied by sweating, increased heart rate and blood pressure, and nausea –small and unmyelinated –0.5-2 m/s –80% of pain afferents –can be blocked by opioid medication
characteristics of A- beta
non-painful sensation related to vibration, stretching, and mechanical pressure
carries epicritic information
What is the neuromatrix pain theory?
Pain is a multidimensional experience produced by “neurosignature” patterns of nerve impulses
Neural network distributed throughout many areas of brain
Neuromatrix genetically determined, modified by sensory inputs
Neurosignature’s output pattern determined by multiple influences (not only somatic sensory)
How long is the duration of pain relief for endogenous opioid system?
4-6 hours
how long is the duration of pain relief for gate control?
as long as the stimulus is applied
physiological effects of heat
Vasodilation
Increase metabolism
For every 10ºC rise in temp, there is 2-3x higher rate of metabolism
Pain relief
Decrease stiffness
Enhance extensibility
Requires elevation of tissue temp to 40-45ºC
Reduce muscle spasms/decreased strength
First 30 minutes after application of heat; returns to pre-tx levels after 2 hours
What is the peak temp time for heat?
within 6-8 minutes it can penetrate about 0.5 cm
What is the longer duration for penetrating 1-2 cm?
about 15-30 minutes
What is the rise in temp for 3 cm?
about 1 degrees celsius
Through what mechanism do hot packs work?
conduction
how many layers of towels do you need for a hot pack?
6-10 layers
When do you reach max results?
after 20 minues
When should you check on the patient with heat?
after 5-6 minutes
What should heat feel like?
warm towels fresh out of the dryer
How does paraffin work?
conduction
mineral oil that alters the melting point and lowers specific heart to make higher temps more tolerable
126-130 degrees
What mechanism does cold use?
conduction. convection and evaporation
what is the ideal tissue temp for cold treatment?
15-25 degrees celcisus
55-77 degreesF
What is the order of sensation for application of cold?
- cold
- warm, burning
- achy, tingling
- numbness
How long should cold pack be applied?
15- 30 minutes
When is cold most effective?
5-10 minutes after an injury and can still be helpful up to 72 hours after injury
physiological effects of cold
Vasoconstriction
Decrease metabolism
Pain relief (decrease nerve conduction velocity)
Augment muscle contraction
What level do you need to reach for ice?
to go beyond numbness
Mechanism of ultrasound
reverse piezoelectric effect
what is the reverse piezoelectric effect?
Electrical current (AC current) applied to lead zirconate titanate crystal in sound head which is converted to mechanical energy
Relationship of frequency, absorption and penetration
the higher the frequency, the higher the absorption BUT less depth of penetration
What ratio is better for the beam of the ultrasound
a lower beam non-uniformity ratio (BNR) is better
If BNR = 5:1 and intensity is 0.5 W/cm2 what is the spatial peak intensity?
- 5 W/cm2
0. 5 * 5= 2.5
What is attenuation?
the decrease in energy due to absorption, reflection and refraction
it is inversely related to penetration
how much does absorption account for attenuation?
absorption accounts for half of attenuation
Tissues with higher attenuation show a…
BIGGER temperature rise
Tissues with higher collagen content have….
HIGHER attenuation
as the frequency of US increases,what happens to attenuation?
attenuation INCREASES
What is the type of tissue with the highest attenuation?
BONE
because it is collagen rich
What type of tissue has the lowest attenuation?
nerves with 0 attenuation
blood fat and muscle are also the lowestq
What are the effects is the duty cycle is 100%
both thermal and mechanical
What is the duty cycle for mechanical only?
20%
How deep does a frequency of 1 MHz go?
up to 5 cm deep
How deep does a frequency of 3 MHz go?
up to 1-2 cm deep
it is absorbed quicker
(higher MHz= higher absorption)
therefore it doesn’t go as deep
What intensity should you use with 1 MHz?
1.5- 2 W/cm2
What intensity should you use with 3 MHz?
0.5 W/cm2
What intensity should you use for non-thermal?
0.5- 1 W/cm2
What should the size of the treatment area be?
2-3 times the size head for 5-10 minutes
What is ultrasound used for?
soft tissue shortening, prolonged inflammation delayed tissue healing pain control patient preference tendon and ligament injuries dermal ulcers carpal tunnel syndrome one fractures resorption of calcium deposits
What effect of ultrasound do you want with prolonged inflammation/delayed tissue healing?
NONthermal (20% duty cycle)
What are the precautions for ultrasound?
acute inflammation
epiphyseal plates
fractures
breast implants
What are the contraindications for ultrasound?
malignancy pregnancy joint cement plastic pacemaker thromophelbiits over the eyes/reproductive organs
What are the precautions for heat?
areas of decreased sensation and circulation poor thermal regulation pregnancy cardiac insuffienciency metal in the area scars and new skin
What are the contraindications?
areas of arterial insufficiency or arterial disease
areas prone to bleeding
acute inflammation
impaired cognitive function
When is paraffin indicated?
arthritis
chronic orthopedic conditions
joint stiffness, contractures
scleroderma
what are the precautions for paraffin?
small scratches or scar tissue
what are the contraindications for paraffin?
open wounds
draining lesions
rashes and infections
water on skin (should be completely dry)
What is dipping?
a thick “glove” should be applied;
abbout 6-10 layers
What is immersion?
more vigorous
once 1 layer “glove” has been formed allow time to harden before placing back into tank
What to know for the board exam about cold treatment
- thought to be most effective 5-10 min after injury but can still be helpful for up to 72 hours after injury
- controls inflammation via vasoconstriction and decreased permeability of vessels
- decreases pain by numbing the area
- prevents secondary hypoxic ischemia
precautions for cold
previous frostbite abnormal skin sensation hypertensive patient because cold causes vasoconstriction decreased cognition very old or very young
contraindications for cold
Raynauds
cold intolerance or hypersensitivity
comprised local circulation (arterial PVD)
What should you do before the first treatment of ice?
check sensitivity using an ice massage for a couple of minutes
What will happen if someone is hypersensitive to the cold?
the skin will blanch and has a leather texture and an elevated surface
How cold should a cold bath or whirlpool be?
13- 18 degrees C
55-65 degrees F
What is the joint distraction mechanism of spinal traction used for?
for stretching facet joint capsules
What occurs from traction?
stretching facet joint capsule)
Simulate mechanoreceptors, decrease joint pain (gentle oscillations)
Increase inferior-superior dimensions of intervertebral foramina → increase space for nerve root
Decrease intradiscal pressure → helps with small disc bulges/protrusions
Gradually elongate soft tissue
Muscle relaxation
When would you perform manual traction?
to determine whether traction is appropriate
also allows traction to be applied in various positions
What is continuous traction used for?
mainly to decrease pressure from muscles and other soft tissues
but typically no longer used with LBP because found to be less effective than exercise
effects of static/sustained traction
muscle relaxation
soft tissue stretch
seperation of joint surfaces
what are the effects of intermittent traction
seperation
stretch
relaxation
mobilization of joints
What are the indications for traction?
disc bulge DDD nerve root compression/impingement stenosis radiculopathy spondylolisthesis degenerative joint disease spondylosis (spinal arthritis) joint hypo mobility compression fracture
What are the precautions for traction?
hypermobility acute phase of healing pregnancy due to increased ligamentous laxity swelling traction anxiety cardiac/respiratory insuffciency complete reduction of symptoms
Contraindications of traction
joint instability RA tumors acute sprain/strain acute inflammation peripherilization uncontrolled HTN TMJ (no cervical traction) fractures hernia
What occurs in the evaluation process for traction?
subjective questioning palpation instability testing of C1-C2!!!!!- transverse and alar ligaments vertebral artery testing neuro screeening cluster items for cervical radiculopathy
What is the positioning for cervical traction
supine or sitting
for upper= neutral
for lower= flexed
for OA= flexed to 2 degrees
What are the four variables for cervical radiculopathy testing?
-spurling test
-cervical distraction test that would reduce UE symptoms
-ULTT
cervical rotation to the involved side is
What is recommended for vertebral artery testing?
Good hx Thorough exam Slow, progressive increase of tx ROM and velocity Pre-manipulative hold (10-15 seconds) Constant monitoring of neuro status
what should you do for future sessions of traction?
increase TIME before increasing force
what are the parameters for cervical traction?
begin force 8-10 lbs
do not exceed 30 lbs
What are the time parameters for traction?
acute-static
muscle spasm - 5on/5off
disc- 60 on/20 off
joint 15 on/15 off
Where is it vulnerable to external compression
at the vertebral foramen of C6
within the foramen transversarium between C2 and C6
at the level of C1 and C2
What position is best for the upper L spine and facet joint problems?
supine
what position is best for the LOWER L spine and posterior disc problems?
prone
What is the classification for lumbar traction?
Leg symptoms
-pain numbness distal to knee
signs of nerve root compression
- pos. SLR that reduces symptoms
parameters for lumbar traction
begin 25-50 lbs
about 1/4 BW is required
What should you do if there is complete pain relief from traction
assess indicators of nerve conduction
if the pain is worsened?
STOP because there could be interruption of nerve conduction otherwise decrease by 50%
If pt responds well to treatment what should you do?
increased the TIME first in future visits
if pt. responds poorly what should you do?
decrease the force by 50%
if pt. experiences partial relief what should you do?
maintain level
what is diathermy?
same as ultrasound except larger treatment area
used thermal and non-thermal
precautions for diathermy
keep away from electronic or magnetic equipment
what is hydrotherapy?
high specific heat and thermal conductivity
heat transfer via conduction and convection
what effects does hydrotherapy have?
cleansing effects cardiovascular effects -enhanced venous return -increased CO respiratory effects renal effects -increased blood flow and volume psychological effects -relaxing
What temperature has the purpose of pain control?
99-110
What temperature is medium for exercise?
79-92
what temp. is used for burns and eptheliazation?
96-98
what temp. is used for open wounds and controlling tone?
92 - 96
what temp is used to reduce inflammation?
32 to 79
What are lasers used for?
soft tissue and bone healing arthritis lymphedema neurological conditions pain control
What do you have to do to lower the frequency?
get a longer wavelength which will essentially penetrate deeper
What is the intensity of radiation proportional to?
the inverse square of distance
What is fluidotherapy?
a dry heating agent that transfers heat via convection
you can perform AROM while being heated at the same time
what is the use of high volt pulsed current?
to treat edema caused by inflammation or lack of motion
also soft tissue healing
used local to the area of swelling; not a muscle
when is the active electrode NEGATIVE?
when we want to repel proteins and attract positively charged chemicals to prevent infection
ex: pitting edema
when is the active electrode POSITIVE?
for later healing it is placed over the affected area to promote further healing
HVPC parameter for tissue healing with inflammation
60-125 Hz
40-100 usec
tingling
negative polarity
HVPC parameter for proliferation
60-125 Hz
40-100 usec
tingling
Positive polarity
HVPC parameter for edema control
100-120 Hz
40-100 usec
tingling
negative polarity
