353 RHPT
CHAPTER II
FARADISM/ FARADIC
CURRENT/BIPHASIC CURRENT
Dr. Amal Abd El Baky, LOGANATHAN CHANDRASEKAR
Lecture outline
2

Introduction and important facts about faradic
current

Physiological Effects of Faradic Current

Indications & Contra indication of faradic current

Parameters &technique of application of faradic
current
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Lecture objectives
3
At the end of lecture the student is able to




Define and outline the principle of faradic current.
List the physiological effects, indication, &
contraindication of Faradic current
Select the appropriate faradic current dose
Demonstrate & apply faradic current on her/ his
colleague
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Introduction
4
Definition:

Faradic current is a short duration interrupted direct
currents with a pulse duration ranging from 0.1 and 1 ms
and a frequency of 50 to 100 HZ.

This is a muscle stimulating current acting directly on the
nerve fiber.

It is normally used to stimulate a muscle with a INTACT
nerve supply
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Waveform
5
It is a graphical representation of the direction, shape,
amplitude, & pulse
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6
Modified Faradic
Currents
• Faradic current can be
interrupted at regular
intervals to avoid
fatigue of muscles
Various forms of
surges results in
different waveform
• trapezoidal,
• triangular,
• saw tooth
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Sinusoidal waveform
Square Waveform
7
Triangular Waveform
Saw tooth Waveform
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8
Surged
Waveform
The intensity of
each successive
pulse gradually
increases
Each impulse
reaches to higher
intensity than that
of preceding one
After the peak
levels either falls
suddenly or
gradually
Pulse Duration
Length of time
that current is
flowing in one
cycle
Pulse
amplitude
Pulse
frequency
The peak
current is the
maximum
amplitude of
the current
Maximum
amplitude of
pulse can be
shown by tip of
highest point of
each phase
Number of
pulses per
second
As frequency of
wave form is
increased the
amplitude tends
to increase &
decrease more
rapidly
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Important points
9

The faradic current was produced in the past by
using the original faradic coil, then by the SmartBristow Faradic coil.

At present the faradic current is produced by the
multivibrator circuit.

Faradic currents are always surged for treatment
purposes to produce a near normal tetanic–like
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contraction and relaxation of muscle.
Con……
10



Surging current means the gradual increase and
decrease of peak intensity.
Surges can be adjusted from 2 to 5 second surge
continuously.
Rest period (pause duration) should be at least 2 to
3 times as long as that of the pulse to give the
muscle sufficient time to recover.
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Con….
11

Functional electrical stimulation (FES) is the electrical
stimulation of the intact lower motor neuron to
initiate contraction of the paralyzed muscles to
produce functional movements.

The negative electrode is called active electrode &
the positive electrode is called passive electrode.
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Con……
12



The passive electrode should be larger than the
active one in most of the cases to reduce the current
density under the same, there by avoiding
unnecessary motor / sensory stimulation.
The active electrode is placed over the motor point.
Motor point is the point at which the main motor
nerve enters the muscle. It is located over the belly
of the muscle at junction between upper and middle
third of muscle
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Physiological Effects of Faradic Current
13
Stimulation of
sensory nerves
Stimulation of
the motor nerves
Reduce swelling
and pain.
Faradic currents
will not
stimulate denervated muscle.
Chemical effects
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PHYSIOLOFICAL EFFECTS OF FARADIC CURRENT
14
Stimulation of sensory nerves



It is not very marked because of the short duration.
It causes reflex vasodilatation of the superficial
blood vessels leading to slight erythema. The
vasodilatation occurs only in the superficial tissues.
When a faradic current is applied to the body, a
mild prickling sensation is experienced.
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PHYSIOLOFICAL EFFECTS OF FARADIC CURRENT
15
Stimulation of the motor nerves



if the current is of sufficient intensity, causes contraction of the muscle
which they supplied by the nerve distal to the point of stimulus.
The contraction is titanic because the stimulus repeated 50 times or
more/s if this type is maintained for more than short time, muscle
fatigue is occurred. So the current is commonly surged to allow for
muscle relaxation .
When the current is surged the contraction gradually increases and
decreases in strength, in a manner similar to a voluntary contraction
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Con……
16
Faradic currents will not stimulate de-nervated
muscle.

The nerve supply must be intact to stimulate the muscle.
The current required to produce contraction of denervated muscle with an impulse lasting for 1 ms is
usually too great to tolerable for treatment purposes.
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Con……
17
Chemical effects

When a direct current is passed through an electrolyte,
chemical changes take place at the electrodes. If the
chemical formed comes in contact with the tissues there
is a danger of electrolytic burns.

With faradic , there is a DANGER of chemical burns,
but it is very minimum due to short duration pulses.
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Indications/ Therapeutic uses
18
Facilitation of
muscle contraction
when inhibited by
pain.
Improved venous
and lymphatic
drainage
Muscle reeducation
Training a new
muscle-action
Prevention and
loosening of
adhesions.
Neuropraxia of
motor nerve
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Indications/ Therapeutic uses cont….
19
Painful knee
syndrome
Spasticity
reduction
In Hysterical
paralysis
Deformity
correction
Trophic
stimulation
Functional
electrical
stimulation
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1-Facilitation of muscle contraction when inhibited by pain
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A muscle contraction is thought to include the following events:



Excitation of the small (fusimotor) efferent fibers, which causes
contraction of the intrafusal muscle fibers.
Stretching of the muscle spindle which stimulates the primary nerve
endings and therefore sends information to the large anterior horn
cells causing an excitation of the extrafusal muscle fibers.
Inhibition of the anterior horn cells supplying the antagonist muscle
group.
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Con….
21



Electrical stimulation of the motor neurons should reduce
the inhibition, so facilitating the transmission of voluntary
impulses to the muscles and also inducing relaxation of
its antagonists.
When muscle contraction is inhibited by pain or recent
injury, electrical stimulation may be of assistance in
establishing voluntary contraction.
The stimulation must be stopped when the good voluntary
contraction obtained.
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22
Meniscectomy
Arthritis
Q’ceps Inhibition – Facilitation of muscle
contraction using Faradic current
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Rotator cuff Injury
Frozen shoulder
Deltoid Inhibition – Facilitation of muscle
contraction using Faradic current
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2- Muscle re-education
24

Muscle contraction is needed to restore the sense of
movement.
Examples:

Prolonged disuse as flat foot

Stress incontinence disuse of pelvic floor muscles

Hallux valgus - disuse of abductor hallucis

Faulty postural habits (incorrect use of back muscles)

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Faradic current stimulation is given


To produce movement so that the lost movement is
produced, as the brain appreciates movement not
muscle action
The patient is asked to perform active contractions
along with the electrical stimulation
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26
Faradic Foot Bath
Stress Incontinence- Pelvic
floor muscle stimulator
Faradic Foot Bath
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3- Training a new muscle-action
27

As in muscle or tendon transplantation, or other reconstructive
procedures

So that its new action is produced & while doing so the
patient should concentrate on the movements & attempt to
assist in voluntary contraction

Generally E.S. is started 5 weeks after the surgeries to
prevent tear of the tendon due to the brisk contraction of the
muscles stimulated
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Tendon
Transfer
Tendon
Transfer
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4-Improved venous and lymphatic drainage
29
e.g. edema, by mainly pumping action of alternate muscle
contraction & relaxation and by joint movement.
Method name

Faradism Under
pressure.
(E.S ►Muscle contraction
► muscle pump action +
combined with
Compression & Elevation
of the limb ►↑ venous &
lymphatic circulation
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5- Prevention and loosening of adhesions.
30



Adhesions which have formed may be stretched and
loosened by muscle contractions, e.g. scar tissue binding
muscles or tendons.
When there is effusion into the tissues, adhesions are liable
to form, but these can be prevented by keeping structures
moving with respect to each other.
If adequate exercise is not possible, electrical stimulation
may be used for this purpose.
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6- Neuropraxia of motor nerve
31

In this case the impulse from the brain are unable to pass
the site of lesion to reach the muscles supplied by the
affected nerve. Consequently voluntary power is reduced
or lost.

There is, however, no degeneration of the nerve, so that if
it is stimulated with faradism below the site of lesion,
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impulses pass to the muscles, causing them
to contract.
NERVE INJURIES
32
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NERVE INJURIES
33
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34
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Example - 1
• Saturday night
palsy – Wrist
drop
(Compression of
the radial nerve
at the radial
groove)
Example - 2
• Following the reinnervations of an
axonotmesis
• Following
repaired
neurotmesis
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36
Wrist Drop
Wrist Drop
Wrist Drop
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37
7- Spasticity
reduction
• To show the patient
that a particular
movement is
available
8-Painful knee
syndrome
• e.g. inhibition of
quadriceps contraction
by pain after knee
surgery (Meniscectomy)
i.e removal of menisci,
rheumatoid arthritis ,
subluxation of patella,
chondromalicia patella
and chronic effusion of
knee.
9- Deformity
Correction
• Deformities in joints
that are due to
muscle tightness can
be corrected using
faradic type current
combined with
stretching
• As in cases of scoliosis
as faradic under
tension is given to the
stretched muscles at
the convex side.
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38
10- Spasticity
reduction
11-Trophic
stimulation
12- Functional
electrical
stimulation
• Stimulation of
antagonist muscles for
reciprocal inhibition
• Aiming for nourishing
effects as in stress
incontinence , Bell’s
palsy, and rheumatoid
arthritis of deformed
hand.
• In order to produce
function movement as
in hemiplegic patients
“ stimulation of the
dorsiflexor muscles”
• Stimulation of spastic
muscles
• Alternated stimulation
for the agonist
followed by
antagonist
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Contra indication
39
Certain
dermatological
condition
Unreliable
patients
Superficial
metal
Cardiac
pacemakers
Thrombosis
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Motor points of upper limb
(anterior &lateral aspect)
40
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Motor points of upper limb
(posterior aspect)
41
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Motor points of upper limb
42
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Motor points of upper limb
(posterior aspect)
43
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Motor points of lower limb
Anterior view
44
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Motor points of lower limb
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Motor points of lower limb
46
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F.E.S – FOR FOOT DROP
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General Points to note – Lab Activity
48
1. Preparation of apparatus
 1.a. Assembling of the apparatus
 1.b. Testing of the machine
2.Preparation of the patient
3.Stimulation of motor points
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Preparation
of Apparatus
• Select E.S & set
towards faradic
current
• Select electrodes
as per the size of
the muscle to be
stimulated & the
area of the
placement of the
passive
electrode.
49
Preparation
of Apparatus
Preparation
of Apparatus
• Soak the pads of the
pad electrode & pen
electrode in a
solution of 1% warm
saline(tap water can
be used in the
absence of warm
saline).
• Connect with the
sockets for the
electrodes on the
machine
• Connect the
electrodes to the
appropriate leads
(RED or BROWN –
passive electrode/
BLACK or BLUE –
active electrode)
• Connect the input
cable to the
power plug
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Testing of
the machine
• It is advisable that
the therapist tests the
machine in front of
the patient.
• The patient sees the
whole procedure – It
alleviates the fear
from the patient
towards the current
treatment
Testing of
the machine
• The testing area –
preferably the
FLEXOR ASPECTS of
the FOREARM &
HAND.
• The passive
electrode in the
CUBITAL
FOSSA.(Median
nerve)
• The active electrode
– a pen electrode
over the THENAR
EMINANCE of the
HAND.
50
Testing of
the machine
• The electrodes are
placed after due skin
preparation.
• The PT switch ON the
machine » ↑ the
intensity/amplitude
gradually + surging
setting.
• A comfortable
contraction of the
muscle is followed by
an adequate rest
period.
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Preparation of the
patient – Point to
focus
• Start from the basic
procedure.
• Explanation about
the nature of
treatment –
SENSATION to be
experienced.
• Ask the patient to
contribute voluntarily
in the production of
movement along with
the stimulus.
51
Preparation of the
patient – Point to
focus
• Report the PT
immediately if any
abnormal feeling such
as burning sensation is
experienced below the
electrodes.
• DON’TS – Not to sleep,
not to touch any metallic
part, not to move the
treatment part etc…
• The sensation of the
patient’s skin over which
the electrodes will be
applied are tested for
pain sensitivity.
Preparation of the
patient – Point to
focus
• The PT uses a pin
with blunted ends –
told to close the eyes
– produce prickling
over selected skin –
looks for the patient
response.
• After the patient was
found suitable for the
stimulation, the PT
cleans the area of
electrode placement
by soap & water.
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Preparation of the patient – Point to focus
• The patient is positioned in a comfortable way.
• The joint over which the muscle so stimulated works remain
preferably in a loose pack position.
• The muscles to be stimulated remains in a partially
shortened position (Middle range of muscle work)
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Important points to
note – Motor point
stimulation
53
• At motor point there are zones of low threshold excitability
• The skin is more sensitive to faradic type current.
Important points to
note – Motor point
stimulation
• Generally, this motor points lies at the junction of the upper
one third & the lower two thirds of the fleshy belly of the
muscle.
Important points to
note – Motor point
stimulation
• Stimulation of the muscle at the motor points isolates the
particular muscle.
• Stimulation of the peripheral nerve at points where they
become superficial produces contraction in the muscle
groups.
• All the muscles have an exact location of motor points in
the muscle, which may vary slightly from person to person.
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Important points to note – Motor point stimulation
• Black / Blue leads serves as negative polarity (ACTIVE)
• Red leads serves as positive polarity (PASSIVE)
Important points to note – Motor point stimulation
• The selection of electrodes can be either 2 pad
electrodes or 1 pad electrode & 1 pen electrode
depending upon the need
Important points to note – Motor point stimulation
54
• As a general rule the passive electrode selected should
be of larger in size compared to the active electrode.
• Testing of the machine should be done before the
treatment application
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• As a general rule, the surge
interval (Rest period) is always
Important points to note
greater than the surge duration
– Motor point stimulation
(Contraction period)
• Increase the intensity of current
intensity / amplitude gradually
Important points to note
to avoid electric shock
– Motor point stimulation
• The treatment is either continued
for the desired duration or
Important points to note
stopped prematurely, if early
– Motor point stimulation
fatigue occurs.
55
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56
Important points to note –
Motor point stimulation
Important points to note –
Motor point stimulation
Appearance of mild
erythema is normal.
If the skin is excessively
red & blister has
occurred inform the
HOD & seek medical
help.
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PRACTICAL / LAB ACTIVITY – MOTOR POINT STIMULATION
Individual M.P.
Baths M.P.
Group M.P.
Stimulation
Stimulation
Stimulation
• The passive electrode (Red
lead) over suitable area of
the body. (Usually for
upper limb stimulation it is
placed over the
• Target muscles:
Q’ceps, Pelvic floor
muscles, small muscles
of the foot.
• Neck (brachial plexus)
• The passive
electrode (Red lead)
– Plexus / nerve
trunk.
• Radial groove (Radial
nerve + Posterior
interroseous nerve)
• Cubital fossa (Median +
Anterior interroseous nerve)
• Posterior aspect of medial
humeral condyle (Ulnar
nerve)
57
• The active electrode
(Black lead) ideally
a pad electrode over
motor points of
different muscles in
the group
• Lumbricals:- Passive
electrode – Below the
heel & the active
electrode –
Metatarsophalangeal
joint.
• Interossei:- Both active &
passive electrode is
placed transversely
across the metatarsals.
• Hallux Valgus:- Passive
electrode - Below the
heel & the active pen
electrode – Over the
motor point of Abductor
Hallucis muscle (Medial
aspect of the ankle)
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PRACTICAL / LAB ACTIVITY – MOTOR POINT STIMULATION
Lumbricals of foot
Action – Flexion of MTP Joint
58
Plantar interossei
Action - Adduction of toes
Dorsal interossei
Action – Abduction of toes
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PRACTICAL / LAB ACTIVITY – MOTOR POINT STIMULATION
Individual M.P.
Stimulation
Individual
Stimulation
• The passive electrode (Red lead)
over suitable area of the body.
(Usually for lower limb stimulation
it is placed over the
• The active electrode – Ideally a
pen electrode over the motor point
of each muscle to produce
individual muscle contraction.
• Lumbosacral region (Femoral &
Sciatic nerves)
• The intensity or amplitude is
gradually increased till a
satisfactory muscle contraction is
obtained
• Popletial region
• Sole of the foot
• Neck of fibula (Common peroneal
nerve)
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PRACTICAL / LAB ACTIVITY – MOTOR POINT
STIMULATION
Group M.P.
Stimulation
60
Group M.P.
Stimulation
• Q’ceps muscle stimulation:-
• Pelvic floor muscle stimulation:-
• Passive electrode – Over the plexus/nerve
trunk/Femoral triangle
• Causes :- Early stage prolapse of uterus +
Stress incontinence.
• Active – Over lower thigh that it covers the
motor point of all the parts of quadriceps.
• Placement of electrode:- Passive –
Lumbosacral plexus at Lumbosacral region.
• Patient position:- Supine / long sitting
• Active electrode – A vaginal or rectal
electrode is used.
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PELVIS FLOOR MUSCLES
62
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SPECIALIZED TYPE OF ELECTRODES TO STIMULATE PELVIC FLOOR MUSCLES
Intrarectal pen electrode used
for giving faradic stimulation.
Ratan et al. BMC
Pediatrics 2009 9:44 doi:10.1
186/1471-2431-9-44
63
VAGINAL ELECTRODE
The inactive electrode.
Ratan et al. BMC
Pediatrics 2009 9:44 doi:10.1186/147
1-2431-9-44
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SPECIALIZED TYPE OF ELECTRODES TO STIMULATE PELVIC FLOOR MUSCLES
Pelvic muscle rehabilitation probe
(anal type) PERIPROBE® Analis
64
Pelvic muscle rehabilitation probe (anal
type) PERIPROBE® ANA 2STW
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The Chartered Society of Physiotherapy recommends the
following standard for electrical devices.
Frequency: 35Hz.
Pulse width: 250µs (0.25ms).
Current type: bi-phasic rectangular.
Intensity: maximum tolerated.
Duty-cycle: 5 seconds on/10 seconds off. Very weak muscles: 5
seconds on/15 seconds off.
Treatment daily/twice daily (home treatment).
Treatment time: 5 minutes initially, gradually increasing to 20 minutes.
It recommends treatment is used for women who can't perform a pelvic floor
contraction on their own. But as soon as you can perform a contraction, you should
switch to pelvic floor exercises.
While using the device, you should also try to join in with the electrically induced
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65 contraction.
http://www.netdoctor.co.uk/womenshealth/sui/devices_005168.htm
66
Pelvic Floor Muscle
stimulation – Points to
consider
• Adequate surging – Very small muscles –
easy fatigue
• The patient told to contract muscles
voluntarily along with the E.S.
Pelvic Floor Muscle
stimulation – Points to
consider
• Patient position – Side lying
• When vaginal / rectal electrode can’t be
used, then small button electrode is
placed over the urogenital / anal region.
Pelvic Floor Muscle
stimulation – Points to
consider
• The intensity of stimulation should be
small
• The duration of treatment should be
short.
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67
Faradic Foot
Bath
Faradic Foot
Bath
• Patient position – Sitting with
back support
• Place the porcelain tray filled
partially with warm water on
the stool
• The patient foot is placed
inside the tray.
• Lumbricals:- Passive
electrode – Below the heel &
the active electrode –
Metatarsophalangeal joint.
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68
Faradic
Foot Bath
• Interossei:- Both active & passive
electrode is placed transversely
across the metatarsals.
Faradic
Foot Bath
• Hallux Valgus:- Passive
electrode - Below the heel & the
active pen electrode – Over the
motor point of Abductor Hallucis
muscle (Medial aspect of the
ankle)
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69
Facial Muscle stimulation
For individual motor point
stimulation
• The passive electrode – Over the cervical
region
• The active electrode – Pen over the motor
point of different facial muscles.
Facial Muscle stimulation
For group motor point
stimulation
• The passive electrode – Over the cervical
region
• The active electrode – Pen over the five
branches of facial nerve.
Facial Muscle stimulation
• Position of the patient – Supine lying
• The intensity of stimulation should be small
• The duration of treatment should be short.
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Facial muscle motor points
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