medium-moderate but pleasant, heat sensation (subacute, resolving inflammatory process)
dosage scheme for diathermy
dose 4=?
heavy-vigorous heating that produces a well-tolerated sensation (chronic)
-pain threshold may be reached, output is moderately lowered to just below maximal toleration
Therapeutic US frequency
.7-3.3 MHz
US uses ________ waves and diathermy uses _______waves?
US uses acoustic
Diathermy uses electromagnetic
Do acoustic waves need a medium to be used?
YES
do electromagnetic waves use a medium?
NO
Therapeutic US and Audible frequencies( decrease or increase) in intensity when they move farther away from their source?
DECREASE
Therapeutic US reaches how high in frequency?
20,000 cycles per second (hz)
Audible sound reaches how high in frequency?
16-20,000 Hz (normal human hearing)
US biophysical effects (6)
increase temp of deep/superficial tissues
increase metabolic rate
decrease pain
alternation of nerve conducting velocity
increase circulation
increase soft tissue extensibility
US frequency
1 MHz deep structures
3 MHz superficial structures
US duty cycle
100% = continous= thermal
20%= pulsed= nonthermal
US intensity
<.5 W/cm2 (acute)
.5-1.2 W/cm2 (subacute)
1.3-3.0W/cm2 (chronic)
Duration of US
normally 5-10 mins
increase duration of US for:
lower intensities
lower frequencies
larger than 2x ERA
thermal effects
decrease duration of US for:
higher intensities
higher frequencies
area smaller than 2x ERA
non thermal effects
ERA =?
area of the transducer from which US energy radiates
always smaller than area of transducer head
Thermal effects of US advantages (5)
acceleration of metabolic rate
reduction or control of pain and muscle spasms
alteration of nerve conduction velocity
increased circulation
increased soft tissue extensability
advantages of non-thermal effects of US (7)
increases intracellular calcium levels
increase skin and cell membrane permeability
promotes normal function of a variety of cell types
increases mast cell degranulation
promotes macrophages
increases nitric oxide synthesis
stimulates proteoglycan synthesis of chondrocytes
EMG biofeedback =?
application of EMG to give a patient info-in the form of visual or auditory about muscle activity
purpose of EMG biofeedback?
increase/decrease a muscle contraction based on feedback given to a patient from a particular muscle
Development of Action Potential:
exits ____and travels to_____
____travels from synaptic cleft to _______ on sarcolemma
acetylcholine _____ permeability of K/NA in postsynaptic membrane which is called ____
endplate potential is conducting _____ from NMJ and can result in AP in ____ sarcolemma
spinal cord travels to NMJ
Ach travels to post synaptic receptors
increases permeability endplate potential
away from adjacent
EMG ultimately detects:
Depolarization of a sarcolemma
small magnitude contraction for EMG
0-10 microvolts
large magnitude for EMG
0-1000 microvolts
Threshold is higher for _______
Threshold is lower for ________
muscle activation
muscle inhibition
motor recruitment =?
conditions in which increasing muscle contraction is the goal
motor inhibition =?
conditions in which decreasing muscle contraction is the goal
EMG and the spine is defined as....?
identify postural dysfunction and stabilization issues that are leading contributors to pain
Compensatory patterning in EMG
prime movers are usually inhibited by pain, deconditioning, or disuse
which = overactivity of accessory muscles= increased pain and creates maladaptive patterns
stabilization =?
muscle activation which accomodates changes in posture rapidly with proper synergistic action and at a high level of skill-thereby reducing unnecessary displacement of the COG
Abnormal recruitment can result in ________and ________
trigger points and myofasical syndrome
microvolts for total body relaxation=?
1 to 3.5 mV
Dosage for total body relaxation
30-60 mins
Responses to total body relaxation
decreases sympathetic nervous system activity
Jacobsen's Technique purpose
help person understand and recognize tension and gain more control over body, decrease pain, maximize benefit of bedrest
Ideal temp for hands is _______and feet is ______
hands: 93-95d
feet: 90d
the use of information from electrical activity of the body to determine a diagnosis in a patient with suspected neurological or neuromuscular dysfunction. Tests may include nerve conduction studies that measure peripheral motor, sensory, and mixed nerve function
electrodiagnostics
at the atomic level, it is the balance between protons and electrons. Like charges repel and unlike charges attract. Charge cannot be created or destroyed. Measured in Coulombs (C)
electrical charge
the unit used to express the force exerted between 2 electrical charges.
Coulomb
Define Coulomb's Law
larger the respective chargers or the closer the 2 charges =the larger the force between them
the work that must be done to move a unit of positive charge (1 coulomb) from one point to the other point (potential energy of the charge) measured in V
potential difference
energy required to move 1 coulomb a distance of 1 meter against a force of 1 newton. represents driving force that makes charged particles move.
Volt
the movement of charged particles thru a conductor in response to an applied electric field. net movement of positive charges per unit time and is measured in amperes
current
movement of 1 coulomb of charge per second
ampere
any object thru which electric charges can flow easily, determined by the ability to give up electrons from the outer orbital shell when placed in an electric field. Tissues containing Na, K and Cl- are good at these (nerves, muscles)
conductors
the ease with which tissues move thru a medium and conduct electricity
conductance
poor conductors of electricity (fat and skin). does not allow easy movement of charged particles in an electric field
insulator
the reciprocal amount of conductance, a measure of the resistance to current flow, measured in Ohms. relative opposition of charged particles in a conductor
resistance
current=voltage/resistance, therefore current increases as the voltage increases or as resistance decreases
Ohm's law
the ability to store charges of opposite signs. A capacitor consists of 2 conductors separated by an insulator. Nerve membrane is an example. measured in farads
capacitance
opposition to alternating currents (similar to the way resistance describes the opposition to direct currents) dependent on resistance and capacitance measured in Ohms
impedence
the point where a nerve enters the muscle, and is usually near the belly of muscle. if motor point is present and responsive you can assume nerve is intact
motor point
when a nerve is damaged, thsi is the area on the muscle where you can get most of the fibers to fire with electrical stimulation. this area is usually where the most muscle fibers are arranged, close to a tendon
area of optimal response
this is how a muscle responds to a particular current, and provides info on the intergrity of alpha motor neurons. test is based on differences between reactions of innervated and denervated muscle to short and long duration electrical stimulation. it helps determine integrity of nerve muscle complex and is an indication of denervation if present.
reaction of degeneration testing
______ RD sluggish or dimished response to alternating or direct current
partial
______RD is no response to alternating or direct current
absolute
amount of time it takes the body to respond to a stimulus that is applied at the motor point of a muscle.
strength duration curve
rheobase=?
amount of current, at a very long pulse duration, required to produce a minimal response in a muscle (strength of a stimulus)
normal is 2-8mA
chronaxie=?
amount of time it takes to produce minimal response at 2x rheobase.
normal range 100 usec
damage to single nerve or nerve group, and results in loss of movement, sensation, and other functions of that nerve
mono-neuropathy
neurological disorder that occurs when many peripheral nerves in the body malfunction simultaneously
poly-neuropathy
conduction velocities of muscle
nerve
muscles 65-75m/sec
nerve 3-5m/sec
properties of excitable tissues:
amplitude (high enough to depolarize)
duration (long enough to excite)
speed of rise (rapid to prevent accomodation)
frequency of motor level stimulation at which smooth tetanic contraction is produced (30-50 pps)
fusion frequency
continuous or uninterrupted unidirectional flow of charged particles
direct current
the continuous or uninterrupted bidirectional flow of charged particles
alternating current
the uni- or bidirectional flow of charged particles which periodically cease for a finite period of time
pulsed current (pulsatile or interrupted)
an isolated electrical event separated by a finite time from the next event
pulse
unidirectional current flow in a mono or bi directional current
phase
shape of the visual representation of pulsed current on a current/time plot
waveform
descriptive characteristics of pulse or waveform
shape, symmetry, balance
maximum current value reached in a monophasic pulse or for any single phase of a biphasic pulse
peak amplitude
maximum current value measure from the peak of the first phase to the peak of the second phase of biphasic pulse
peak to peak amplitude
elapsed time between the beginning and the end of one phase
phase duration
elapsed time between the beginning and the end of all phases in a single pulse; on the clinical stimulators. often labeled width,
pulse duration
T/F Phase duration is synonymous with pulse duration in a monophasic pulse
FALSE
elapsed time between 2 successive phases of a pulse, also known as the intrapulse interval
interphase interval
the time for the leading edge of the phase to increase in amplitude from the 0 current baseline to peak amplitude of 1 phase
rise time
time integral of current for a single phase; represented by the area under a single phase waveform
phase charge
time integral of a single pulse for the current waveform over the entire pulse
pulse charge
time between end of one pulse and the beginning of the next pulse in a series, the time between successive pulses
interpulse interval
# of pulses per unit time (pps) on clinical stimulators, often called pulse rate
frequency
IIIIII IiIiI
_________ what type of modulation is this?
amplitude
I I I I I I I IIIIIIIII
______ ______ why type of modulation is this?
frequency
timing modulation:
train
individual lines (pulses)
timing modulation:
bursts
packages of trains
envelope of AC currents
duty cycle =?
on time/ on time + off time X 100
conduction in normal propogation
orthodronic conduction
conduction in opposite propogation
antidromic conduction
sensory level stimulation
-gait theory of analgesia
higher frequency 80-125 pps
feel buzzing, tingling, tapping
motor level stimulation
longer pulse duration
lower frequency
1-5 pps
taps into endorphins for analgesia
microshock
when applied directly to heart with sufficient current intensity (V fib)
macroshock
applied from surface of the body thru skin, large amount of current needed
Identify voltage needed to do damage
burns
respiratory/cardiac arrest
involuntary jerking
chemical burns
coagulation
burns--250mA
respiratory/cardiac arrest--80mA
involuntary jerking --80 mA
chemical burns --DC
coagulation --<5mA
Therapeutic applications for DC current (4)
wound/soft tissue healing
denervated muscles
iontophoresis
electrodiagnostic testing
Therapeutic applications for low AC current (7)
battery TENS
FES
variable pulse generator
pain modulation
strengthening
functional retraining
fracture healing
Therapeutic applications for high pulsed current (5)
pain modulation
tissue healing
muscle re-ed
edema control
muscle strengthening (small muscles)
therapeutic applications for interferential current (3)
