MEDIUM FREQUENCY CURRENT

INTERFRENTIAL CURRENT (IFC)

RUSSIAN CURRENT

INTERFRENTIAL CURRENT (IFC)

106

Contents Definition of IFC Production of IFC Physiological and Therapeutic Effects of IFC indications and contraindications of IFC dangers of IFC Techniques of application IFC

Objectives

By the end of this topic the students should be able to

Define interferential current Understand the production of IFC Recognize the Physiological and Therapeutic Effects of IFC Discuss the indications and contraindications of IFC Identify the dangers of IFC Utilize different application techniques in different cases

Definition Interferential therapy is a form of electrical treatment in

which two alternating medium-frequency currents are used to produce a low-frequency effect Frequency used for interferential therapy is

Interferential currents have advantage of reducing the skin impedance or resistance and thus the discomfort normally incurred by traditional low-frequency currents but still producing low-frequency effects within the tissues They are used to produce effects in deeper tissues of the body

Production of interferential current IFC is produced by mixing two medium-frequency currents

that are slightly out of phase either by applying them so that they lsquointerferersquo within tissues or alternatively by mixing them within the stimulator prior to application

107

One current is normally of fixed frequency for example at 4000 Hz and the other current is adjustable for example between 4000 and 4200 Hz

Two currents summate or cancel each other out in a predictable manner producing the resultant amplitude-modulated lsquointerferential currentrsquo

The frequency of the resultant current will be equal to the mean of the two original currents and will vary in amplitude at a frequency equal to the difference between these two currents as shown in fig (1)

Figure (1) Interference of two medium-frequency currents (b) Partial beating

Area of Interference It is the area where interferential current is set-up

108

The pattern of the interferential area may be static or dynamic

Static Interference The area in which the produced interferential current remains stationary This area of static interference gives an appearance of clove leaf as a result of the vector addition of two currents and it lies to 45deg angles to the perpendicular lines from each electrode

Figure (2) Static Interference

Dynamic Interference The area in which interference current is developed is moving in a to and fro manner through 45deg It is obtained by varying the current intensity in suitable manner Current is varied from 50 to 100 This dynamic area of interference is also called as vector sweep vector scan It can also be rotated through 90deg

109

Figure (3) Dynamic Interference

Physiological and Therapeutic Effects of IFC

The current flowing between each pair of electrodes is insufficient to stimulate nerve and muscle directly until amplitude is modulated by interference Interferential therapy thus reduces the stimulation of cutaneous sensory nerves near the electrodes whilst promoting the effect upon deep tissues

The physiological effects depend on the factors such as the 1- Magnitude of the current 2- Mode (constant sweep) 3- Frequency used 4- The accuracy with which the electrodes are placed5- The pathological condition

The common effects produced are 1-Pain reliefIFC can be used in management of acute and chronic pain of different originsIf a constant beat in the range of 1-100 Hz is used this causes a tingling sensation which after 15 min treatment can produce relief of pain for up to one hour

110

Mechanism of pain control by interferential therapy-Stimulation with the higher frequencies about 100 Hz at sensory level stimulation stimulate the pain gate mechanism and thereby mask the pain symptoms-Stimulation with lower frequencies up to 10 Hz at motor level intensities can be used to activate the opiate mechanisms again providing a degree of relief-Interferential current has been claimed to improve the circulation of blood and swelling which may wash away the chemicals that stimulate nociceptive nerve endings Reduced swelling may concomitantly reduce tissue pressure These phenomena are reported to occur because of mild muscle contraction or action on the autonomic nervous system decreasing the tone of the blood vessels

2-Motor stimulation-As with other forms of electrical stimulation as IFC intensity is increased there is a progressive recruitment of sensory and motor responses-Normal innervated muscles contract if interferential frequencies between 1-100 Hz are used -Muscle contraction is produced with little sensory stimulation and can be of deeply placed muscles eg Pelvic floor muscles

3-Absorption of exudatesThis is accelerated by a frequency of 1-10 Hz as rhythmical pumping action is produced by muscle contraction and there is possibly an effect on the autonomic nerves which can affect the diameter of the blood vessels and therefore the circulation Both of these factors help in absorption of exudates and reduction of edema

Indications of Interferential Current 1-Peripheral vascular disease (PVD) i Vasoconstrictive disease (Raynaudrsquos Disease)

111

A disorder where the exposure to cold causes sudden contraction of small arteries supplying the fingers and toes ii Venous insufficiency Inability of veins to pump the blood towards the heartiii Burgerrsquos disease It is a combination of thrombosis inflammation and obliteration of small and medium sized arteries The disease begins in distal small arteries and spreads upwards

2-Facial nerve neuritis 3-Orthopedic conditions -Joint sprains -Fracture complications like delayed union non-union amp retarded callous formation-Osteoarthritis-spondylosis-Frozen shoulder-Chondromalacia

4-Gynecological Problems -Stress incontinence -Urinary frequency -Pelvic floor dysfunction

5-Pain (All types of musculoskeletal pains)-Low back pain -Brachial neuralgia Sever pain in the course or distribution of the brachial nerve due to irritation or damage to the brachial nerve-Sciatica Pain in the distribution of sciatic nerve due to lateral disc protrusion on L4 andor L5 spinal nerve roots is called sciatica -Phantom limb pain Pain felt as though arising in an amputated limb is called phantom limb pain - Myalgia Pain in the muscles is known as myalgia 6-Myositis Bursitis and tendinitis

112

7-Muscle re-education and muscle strengthening

Contraindications1) Malignant tumours 2) Arterial disease the stimulatory effect of the current could produce embolus3) Deep Vein Thrombosis 4) Infective conditions 5) Artificial pacemakers on the heart 6) Pregnant Uterus 7) Condition of haemorrhage 8) Large open wounds these will cause concentration of the current and distortion of the IF field9) Dermatological conditions 10) Senile or confused patients 11) Advanced cardiac disease

Advantages of Interferential Current1-Large doses of the current can be produced without producing chemical burn2-The current can be localized more effectively in a specific area by careful positioning of the electrodes 3-Skin resistance is very much lowered hence there is no irritation of skin and thus interferential currents can be given for longer period of time 4-Interferential currents are used to treat deeper tissues as amplitude-modulated frequency is produced deep in the tissue 5-It can give sensory stimulation and motor stimulation 6-Interferential currents are used to treat larger area

Hazards (Dangers) of Interferential Current 1048599 BurnsBurns may be caused by -bare metal electrode against the skin-Insufficient moisture of the pad -Increased intensity with skin currents1048599Hematoma

113

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Contents Definition of IFC Production of IFC Physiological and Therapeutic Effects of IFC indications and contraindications of IFC dangers of IFC Techniques of application IFC

Objectives

By the end of this topic the students should be able to

Define interferential current Understand the production of IFC Recognize the Physiological and Therapeutic Effects of IFC Discuss the indications and contraindications of IFC Identify the dangers of IFC Utilize different application techniques in different cases

Definition Interferential therapy is a form of electrical treatment in

which two alternating medium-frequency currents are used to produce a low-frequency effect Frequency used for interferential therapy is

Interferential currents have advantage of reducing the skin impedance or resistance and thus the discomfort normally incurred by traditional low-frequency currents but still producing low-frequency effects within the tissues They are used to produce effects in deeper tissues of the body

Production of interferential current IFC is produced by mixing two medium-frequency currents

that are slightly out of phase either by applying them so that they lsquointerferersquo within tissues or alternatively by mixing them within the stimulator prior to application

107

One current is normally of fixed frequency for example at 4000 Hz and the other current is adjustable for example between 4000 and 4200 Hz

Two currents summate or cancel each other out in a predictable manner producing the resultant amplitude-modulated lsquointerferential currentrsquo

The frequency of the resultant current will be equal to the mean of the two original currents and will vary in amplitude at a frequency equal to the difference between these two currents as shown in fig (1)

Figure (1) Interference of two medium-frequency currents (b) Partial beating

Area of Interference It is the area where interferential current is set-up

108

The pattern of the interferential area may be static or dynamic

Static Interference The area in which the produced interferential current remains stationary This area of static interference gives an appearance of clove leaf as a result of the vector addition of two currents and it lies to 45deg angles to the perpendicular lines from each electrode

Figure (2) Static Interference

Dynamic Interference The area in which interference current is developed is moving in a to and fro manner through 45deg It is obtained by varying the current intensity in suitable manner Current is varied from 50 to 100 This dynamic area of interference is also called as vector sweep vector scan It can also be rotated through 90deg

109

Figure (3) Dynamic Interference

Physiological and Therapeutic Effects of IFC

The current flowing between each pair of electrodes is insufficient to stimulate nerve and muscle directly until amplitude is modulated by interference Interferential therapy thus reduces the stimulation of cutaneous sensory nerves near the electrodes whilst promoting the effect upon deep tissues

The physiological effects depend on the factors such as the 1- Magnitude of the current 2- Mode (constant sweep) 3- Frequency used 4- The accuracy with which the electrodes are placed5- The pathological condition

The common effects produced are 1-Pain reliefIFC can be used in management of acute and chronic pain of different originsIf a constant beat in the range of 1-100 Hz is used this causes a tingling sensation which after 15 min treatment can produce relief of pain for up to one hour

110

Mechanism of pain control by interferential therapy-Stimulation with the higher frequencies about 100 Hz at sensory level stimulation stimulate the pain gate mechanism and thereby mask the pain symptoms-Stimulation with lower frequencies up to 10 Hz at motor level intensities can be used to activate the opiate mechanisms again providing a degree of relief-Interferential current has been claimed to improve the circulation of blood and swelling which may wash away the chemicals that stimulate nociceptive nerve endings Reduced swelling may concomitantly reduce tissue pressure These phenomena are reported to occur because of mild muscle contraction or action on the autonomic nervous system decreasing the tone of the blood vessels

2-Motor stimulation-As with other forms of electrical stimulation as IFC intensity is increased there is a progressive recruitment of sensory and motor responses-Normal innervated muscles contract if interferential frequencies between 1-100 Hz are used -Muscle contraction is produced with little sensory stimulation and can be of deeply placed muscles eg Pelvic floor muscles

3-Absorption of exudatesThis is accelerated by a frequency of 1-10 Hz as rhythmical pumping action is produced by muscle contraction and there is possibly an effect on the autonomic nerves which can affect the diameter of the blood vessels and therefore the circulation Both of these factors help in absorption of exudates and reduction of edema

Indications of Interferential Current 1-Peripheral vascular disease (PVD) i Vasoconstrictive disease (Raynaudrsquos Disease)

111

A disorder where the exposure to cold causes sudden contraction of small arteries supplying the fingers and toes ii Venous insufficiency Inability of veins to pump the blood towards the heartiii Burgerrsquos disease It is a combination of thrombosis inflammation and obliteration of small and medium sized arteries The disease begins in distal small arteries and spreads upwards

2-Facial nerve neuritis 3-Orthopedic conditions -Joint sprains -Fracture complications like delayed union non-union amp retarded callous formation-Osteoarthritis-spondylosis-Frozen shoulder-Chondromalacia

4-Gynecological Problems -Stress incontinence -Urinary frequency -Pelvic floor dysfunction

5-Pain (All types of musculoskeletal pains)-Low back pain -Brachial neuralgia Sever pain in the course or distribution of the brachial nerve due to irritation or damage to the brachial nerve-Sciatica Pain in the distribution of sciatic nerve due to lateral disc protrusion on L4 andor L5 spinal nerve roots is called sciatica -Phantom limb pain Pain felt as though arising in an amputated limb is called phantom limb pain - Myalgia Pain in the muscles is known as myalgia 6-Myositis Bursitis and tendinitis

112

7-Muscle re-education and muscle strengthening

Contraindications1) Malignant tumours 2) Arterial disease the stimulatory effect of the current could produce embolus3) Deep Vein Thrombosis 4) Infective conditions 5) Artificial pacemakers on the heart 6) Pregnant Uterus 7) Condition of haemorrhage 8) Large open wounds these will cause concentration of the current and distortion of the IF field9) Dermatological conditions 10) Senile or confused patients 11) Advanced cardiac disease

Advantages of Interferential Current1-Large doses of the current can be produced without producing chemical burn2-The current can be localized more effectively in a specific area by careful positioning of the electrodes 3-Skin resistance is very much lowered hence there is no irritation of skin and thus interferential currents can be given for longer period of time 4-Interferential currents are used to treat deeper tissues as amplitude-modulated frequency is produced deep in the tissue 5-It can give sensory stimulation and motor stimulation 6-Interferential currents are used to treat larger area

Hazards (Dangers) of Interferential Current 1048599 BurnsBurns may be caused by -bare metal electrode against the skin-Insufficient moisture of the pad -Increased intensity with skin currents1048599Hematoma

113

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

One current is normally of fixed frequency for example at 4000 Hz and the other current is adjustable for example between 4000 and 4200 Hz

Two currents summate or cancel each other out in a predictable manner producing the resultant amplitude-modulated lsquointerferential currentrsquo

The frequency of the resultant current will be equal to the mean of the two original currents and will vary in amplitude at a frequency equal to the difference between these two currents as shown in fig (1)

Figure (1) Interference of two medium-frequency currents (b) Partial beating

Area of Interference It is the area where interferential current is set-up

108

The pattern of the interferential area may be static or dynamic

Static Interference The area in which the produced interferential current remains stationary This area of static interference gives an appearance of clove leaf as a result of the vector addition of two currents and it lies to 45deg angles to the perpendicular lines from each electrode

Figure (2) Static Interference

Dynamic Interference The area in which interference current is developed is moving in a to and fro manner through 45deg It is obtained by varying the current intensity in suitable manner Current is varied from 50 to 100 This dynamic area of interference is also called as vector sweep vector scan It can also be rotated through 90deg

109

Figure (3) Dynamic Interference

Physiological and Therapeutic Effects of IFC

The current flowing between each pair of electrodes is insufficient to stimulate nerve and muscle directly until amplitude is modulated by interference Interferential therapy thus reduces the stimulation of cutaneous sensory nerves near the electrodes whilst promoting the effect upon deep tissues

The physiological effects depend on the factors such as the 1- Magnitude of the current 2- Mode (constant sweep) 3- Frequency used 4- The accuracy with which the electrodes are placed5- The pathological condition

The common effects produced are 1-Pain reliefIFC can be used in management of acute and chronic pain of different originsIf a constant beat in the range of 1-100 Hz is used this causes a tingling sensation which after 15 min treatment can produce relief of pain for up to one hour

110

Mechanism of pain control by interferential therapy-Stimulation with the higher frequencies about 100 Hz at sensory level stimulation stimulate the pain gate mechanism and thereby mask the pain symptoms-Stimulation with lower frequencies up to 10 Hz at motor level intensities can be used to activate the opiate mechanisms again providing a degree of relief-Interferential current has been claimed to improve the circulation of blood and swelling which may wash away the chemicals that stimulate nociceptive nerve endings Reduced swelling may concomitantly reduce tissue pressure These phenomena are reported to occur because of mild muscle contraction or action on the autonomic nervous system decreasing the tone of the blood vessels

2-Motor stimulation-As with other forms of electrical stimulation as IFC intensity is increased there is a progressive recruitment of sensory and motor responses-Normal innervated muscles contract if interferential frequencies between 1-100 Hz are used -Muscle contraction is produced with little sensory stimulation and can be of deeply placed muscles eg Pelvic floor muscles

3-Absorption of exudatesThis is accelerated by a frequency of 1-10 Hz as rhythmical pumping action is produced by muscle contraction and there is possibly an effect on the autonomic nerves which can affect the diameter of the blood vessels and therefore the circulation Both of these factors help in absorption of exudates and reduction of edema

Indications of Interferential Current 1-Peripheral vascular disease (PVD) i Vasoconstrictive disease (Raynaudrsquos Disease)

111

A disorder where the exposure to cold causes sudden contraction of small arteries supplying the fingers and toes ii Venous insufficiency Inability of veins to pump the blood towards the heartiii Burgerrsquos disease It is a combination of thrombosis inflammation and obliteration of small and medium sized arteries The disease begins in distal small arteries and spreads upwards

2-Facial nerve neuritis 3-Orthopedic conditions -Joint sprains -Fracture complications like delayed union non-union amp retarded callous formation-Osteoarthritis-spondylosis-Frozen shoulder-Chondromalacia

4-Gynecological Problems -Stress incontinence -Urinary frequency -Pelvic floor dysfunction

5-Pain (All types of musculoskeletal pains)-Low back pain -Brachial neuralgia Sever pain in the course or distribution of the brachial nerve due to irritation or damage to the brachial nerve-Sciatica Pain in the distribution of sciatic nerve due to lateral disc protrusion on L4 andor L5 spinal nerve roots is called sciatica -Phantom limb pain Pain felt as though arising in an amputated limb is called phantom limb pain - Myalgia Pain in the muscles is known as myalgia 6-Myositis Bursitis and tendinitis

112

7-Muscle re-education and muscle strengthening

Contraindications1) Malignant tumours 2) Arterial disease the stimulatory effect of the current could produce embolus3) Deep Vein Thrombosis 4) Infective conditions 5) Artificial pacemakers on the heart 6) Pregnant Uterus 7) Condition of haemorrhage 8) Large open wounds these will cause concentration of the current and distortion of the IF field9) Dermatological conditions 10) Senile or confused patients 11) Advanced cardiac disease

Advantages of Interferential Current1-Large doses of the current can be produced without producing chemical burn2-The current can be localized more effectively in a specific area by careful positioning of the electrodes 3-Skin resistance is very much lowered hence there is no irritation of skin and thus interferential currents can be given for longer period of time 4-Interferential currents are used to treat deeper tissues as amplitude-modulated frequency is produced deep in the tissue 5-It can give sensory stimulation and motor stimulation 6-Interferential currents are used to treat larger area

Hazards (Dangers) of Interferential Current 1048599 BurnsBurns may be caused by -bare metal electrode against the skin-Insufficient moisture of the pad -Increased intensity with skin currents1048599Hematoma

113

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

The pattern of the interferential area may be static or dynamic

Static Interference The area in which the produced interferential current remains stationary This area of static interference gives an appearance of clove leaf as a result of the vector addition of two currents and it lies to 45deg angles to the perpendicular lines from each electrode

Figure (2) Static Interference

Dynamic Interference The area in which interference current is developed is moving in a to and fro manner through 45deg It is obtained by varying the current intensity in suitable manner Current is varied from 50 to 100 This dynamic area of interference is also called as vector sweep vector scan It can also be rotated through 90deg

109

Figure (3) Dynamic Interference

Physiological and Therapeutic Effects of IFC

The current flowing between each pair of electrodes is insufficient to stimulate nerve and muscle directly until amplitude is modulated by interference Interferential therapy thus reduces the stimulation of cutaneous sensory nerves near the electrodes whilst promoting the effect upon deep tissues

The physiological effects depend on the factors such as the 1- Magnitude of the current 2- Mode (constant sweep) 3- Frequency used 4- The accuracy with which the electrodes are placed5- The pathological condition

The common effects produced are 1-Pain reliefIFC can be used in management of acute and chronic pain of different originsIf a constant beat in the range of 1-100 Hz is used this causes a tingling sensation which after 15 min treatment can produce relief of pain for up to one hour

110

Mechanism of pain control by interferential therapy-Stimulation with the higher frequencies about 100 Hz at sensory level stimulation stimulate the pain gate mechanism and thereby mask the pain symptoms-Stimulation with lower frequencies up to 10 Hz at motor level intensities can be used to activate the opiate mechanisms again providing a degree of relief-Interferential current has been claimed to improve the circulation of blood and swelling which may wash away the chemicals that stimulate nociceptive nerve endings Reduced swelling may concomitantly reduce tissue pressure These phenomena are reported to occur because of mild muscle contraction or action on the autonomic nervous system decreasing the tone of the blood vessels

2-Motor stimulation-As with other forms of electrical stimulation as IFC intensity is increased there is a progressive recruitment of sensory and motor responses-Normal innervated muscles contract if interferential frequencies between 1-100 Hz are used -Muscle contraction is produced with little sensory stimulation and can be of deeply placed muscles eg Pelvic floor muscles

3-Absorption of exudatesThis is accelerated by a frequency of 1-10 Hz as rhythmical pumping action is produced by muscle contraction and there is possibly an effect on the autonomic nerves which can affect the diameter of the blood vessels and therefore the circulation Both of these factors help in absorption of exudates and reduction of edema

Indications of Interferential Current 1-Peripheral vascular disease (PVD) i Vasoconstrictive disease (Raynaudrsquos Disease)

111

A disorder where the exposure to cold causes sudden contraction of small arteries supplying the fingers and toes ii Venous insufficiency Inability of veins to pump the blood towards the heartiii Burgerrsquos disease It is a combination of thrombosis inflammation and obliteration of small and medium sized arteries The disease begins in distal small arteries and spreads upwards

2-Facial nerve neuritis 3-Orthopedic conditions -Joint sprains -Fracture complications like delayed union non-union amp retarded callous formation-Osteoarthritis-spondylosis-Frozen shoulder-Chondromalacia

4-Gynecological Problems -Stress incontinence -Urinary frequency -Pelvic floor dysfunction

5-Pain (All types of musculoskeletal pains)-Low back pain -Brachial neuralgia Sever pain in the course or distribution of the brachial nerve due to irritation or damage to the brachial nerve-Sciatica Pain in the distribution of sciatic nerve due to lateral disc protrusion on L4 andor L5 spinal nerve roots is called sciatica -Phantom limb pain Pain felt as though arising in an amputated limb is called phantom limb pain - Myalgia Pain in the muscles is known as myalgia 6-Myositis Bursitis and tendinitis

112

7-Muscle re-education and muscle strengthening

Contraindications1) Malignant tumours 2) Arterial disease the stimulatory effect of the current could produce embolus3) Deep Vein Thrombosis 4) Infective conditions 5) Artificial pacemakers on the heart 6) Pregnant Uterus 7) Condition of haemorrhage 8) Large open wounds these will cause concentration of the current and distortion of the IF field9) Dermatological conditions 10) Senile or confused patients 11) Advanced cardiac disease

Advantages of Interferential Current1-Large doses of the current can be produced without producing chemical burn2-The current can be localized more effectively in a specific area by careful positioning of the electrodes 3-Skin resistance is very much lowered hence there is no irritation of skin and thus interferential currents can be given for longer period of time 4-Interferential currents are used to treat deeper tissues as amplitude-modulated frequency is produced deep in the tissue 5-It can give sensory stimulation and motor stimulation 6-Interferential currents are used to treat larger area

Hazards (Dangers) of Interferential Current 1048599 BurnsBurns may be caused by -bare metal electrode against the skin-Insufficient moisture of the pad -Increased intensity with skin currents1048599Hematoma

113

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Figure (3) Dynamic Interference

Physiological and Therapeutic Effects of IFC

The current flowing between each pair of electrodes is insufficient to stimulate nerve and muscle directly until amplitude is modulated by interference Interferential therapy thus reduces the stimulation of cutaneous sensory nerves near the electrodes whilst promoting the effect upon deep tissues

The physiological effects depend on the factors such as the 1- Magnitude of the current 2- Mode (constant sweep) 3- Frequency used 4- The accuracy with which the electrodes are placed5- The pathological condition

The common effects produced are 1-Pain reliefIFC can be used in management of acute and chronic pain of different originsIf a constant beat in the range of 1-100 Hz is used this causes a tingling sensation which after 15 min treatment can produce relief of pain for up to one hour

110

Mechanism of pain control by interferential therapy-Stimulation with the higher frequencies about 100 Hz at sensory level stimulation stimulate the pain gate mechanism and thereby mask the pain symptoms-Stimulation with lower frequencies up to 10 Hz at motor level intensities can be used to activate the opiate mechanisms again providing a degree of relief-Interferential current has been claimed to improve the circulation of blood and swelling which may wash away the chemicals that stimulate nociceptive nerve endings Reduced swelling may concomitantly reduce tissue pressure These phenomena are reported to occur because of mild muscle contraction or action on the autonomic nervous system decreasing the tone of the blood vessels

2-Motor stimulation-As with other forms of electrical stimulation as IFC intensity is increased there is a progressive recruitment of sensory and motor responses-Normal innervated muscles contract if interferential frequencies between 1-100 Hz are used -Muscle contraction is produced with little sensory stimulation and can be of deeply placed muscles eg Pelvic floor muscles

3-Absorption of exudatesThis is accelerated by a frequency of 1-10 Hz as rhythmical pumping action is produced by muscle contraction and there is possibly an effect on the autonomic nerves which can affect the diameter of the blood vessels and therefore the circulation Both of these factors help in absorption of exudates and reduction of edema

Indications of Interferential Current 1-Peripheral vascular disease (PVD) i Vasoconstrictive disease (Raynaudrsquos Disease)

111

A disorder where the exposure to cold causes sudden contraction of small arteries supplying the fingers and toes ii Venous insufficiency Inability of veins to pump the blood towards the heartiii Burgerrsquos disease It is a combination of thrombosis inflammation and obliteration of small and medium sized arteries The disease begins in distal small arteries and spreads upwards

2-Facial nerve neuritis 3-Orthopedic conditions -Joint sprains -Fracture complications like delayed union non-union amp retarded callous formation-Osteoarthritis-spondylosis-Frozen shoulder-Chondromalacia

4-Gynecological Problems -Stress incontinence -Urinary frequency -Pelvic floor dysfunction

5-Pain (All types of musculoskeletal pains)-Low back pain -Brachial neuralgia Sever pain in the course or distribution of the brachial nerve due to irritation or damage to the brachial nerve-Sciatica Pain in the distribution of sciatic nerve due to lateral disc protrusion on L4 andor L5 spinal nerve roots is called sciatica -Phantom limb pain Pain felt as though arising in an amputated limb is called phantom limb pain - Myalgia Pain in the muscles is known as myalgia 6-Myositis Bursitis and tendinitis

112

7-Muscle re-education and muscle strengthening

Contraindications1) Malignant tumours 2) Arterial disease the stimulatory effect of the current could produce embolus3) Deep Vein Thrombosis 4) Infective conditions 5) Artificial pacemakers on the heart 6) Pregnant Uterus 7) Condition of haemorrhage 8) Large open wounds these will cause concentration of the current and distortion of the IF field9) Dermatological conditions 10) Senile or confused patients 11) Advanced cardiac disease

Advantages of Interferential Current1-Large doses of the current can be produced without producing chemical burn2-The current can be localized more effectively in a specific area by careful positioning of the electrodes 3-Skin resistance is very much lowered hence there is no irritation of skin and thus interferential currents can be given for longer period of time 4-Interferential currents are used to treat deeper tissues as amplitude-modulated frequency is produced deep in the tissue 5-It can give sensory stimulation and motor stimulation 6-Interferential currents are used to treat larger area

Hazards (Dangers) of Interferential Current 1048599 BurnsBurns may be caused by -bare metal electrode against the skin-Insufficient moisture of the pad -Increased intensity with skin currents1048599Hematoma

113

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Mechanism of pain control by interferential therapy-Stimulation with the higher frequencies about 100 Hz at sensory level stimulation stimulate the pain gate mechanism and thereby mask the pain symptoms-Stimulation with lower frequencies up to 10 Hz at motor level intensities can be used to activate the opiate mechanisms again providing a degree of relief-Interferential current has been claimed to improve the circulation of blood and swelling which may wash away the chemicals that stimulate nociceptive nerve endings Reduced swelling may concomitantly reduce tissue pressure These phenomena are reported to occur because of mild muscle contraction or action on the autonomic nervous system decreasing the tone of the blood vessels

2-Motor stimulation-As with other forms of electrical stimulation as IFC intensity is increased there is a progressive recruitment of sensory and motor responses-Normal innervated muscles contract if interferential frequencies between 1-100 Hz are used -Muscle contraction is produced with little sensory stimulation and can be of deeply placed muscles eg Pelvic floor muscles

3-Absorption of exudatesThis is accelerated by a frequency of 1-10 Hz as rhythmical pumping action is produced by muscle contraction and there is possibly an effect on the autonomic nerves which can affect the diameter of the blood vessels and therefore the circulation Both of these factors help in absorption of exudates and reduction of edema

Indications of Interferential Current 1-Peripheral vascular disease (PVD) i Vasoconstrictive disease (Raynaudrsquos Disease)

111

A disorder where the exposure to cold causes sudden contraction of small arteries supplying the fingers and toes ii Venous insufficiency Inability of veins to pump the blood towards the heartiii Burgerrsquos disease It is a combination of thrombosis inflammation and obliteration of small and medium sized arteries The disease begins in distal small arteries and spreads upwards

2-Facial nerve neuritis 3-Orthopedic conditions -Joint sprains -Fracture complications like delayed union non-union amp retarded callous formation-Osteoarthritis-spondylosis-Frozen shoulder-Chondromalacia

4-Gynecological Problems -Stress incontinence -Urinary frequency -Pelvic floor dysfunction

5-Pain (All types of musculoskeletal pains)-Low back pain -Brachial neuralgia Sever pain in the course or distribution of the brachial nerve due to irritation or damage to the brachial nerve-Sciatica Pain in the distribution of sciatic nerve due to lateral disc protrusion on L4 andor L5 spinal nerve roots is called sciatica -Phantom limb pain Pain felt as though arising in an amputated limb is called phantom limb pain - Myalgia Pain in the muscles is known as myalgia 6-Myositis Bursitis and tendinitis

112

7-Muscle re-education and muscle strengthening

Contraindications1) Malignant tumours 2) Arterial disease the stimulatory effect of the current could produce embolus3) Deep Vein Thrombosis 4) Infective conditions 5) Artificial pacemakers on the heart 6) Pregnant Uterus 7) Condition of haemorrhage 8) Large open wounds these will cause concentration of the current and distortion of the IF field9) Dermatological conditions 10) Senile or confused patients 11) Advanced cardiac disease

Advantages of Interferential Current1-Large doses of the current can be produced without producing chemical burn2-The current can be localized more effectively in a specific area by careful positioning of the electrodes 3-Skin resistance is very much lowered hence there is no irritation of skin and thus interferential currents can be given for longer period of time 4-Interferential currents are used to treat deeper tissues as amplitude-modulated frequency is produced deep in the tissue 5-It can give sensory stimulation and motor stimulation 6-Interferential currents are used to treat larger area

Hazards (Dangers) of Interferential Current 1048599 BurnsBurns may be caused by -bare metal electrode against the skin-Insufficient moisture of the pad -Increased intensity with skin currents1048599Hematoma

113

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

A disorder where the exposure to cold causes sudden contraction of small arteries supplying the fingers and toes ii Venous insufficiency Inability of veins to pump the blood towards the heartiii Burgerrsquos disease It is a combination of thrombosis inflammation and obliteration of small and medium sized arteries The disease begins in distal small arteries and spreads upwards

2-Facial nerve neuritis 3-Orthopedic conditions -Joint sprains -Fracture complications like delayed union non-union amp retarded callous formation-Osteoarthritis-spondylosis-Frozen shoulder-Chondromalacia

4-Gynecological Problems -Stress incontinence -Urinary frequency -Pelvic floor dysfunction

5-Pain (All types of musculoskeletal pains)-Low back pain -Brachial neuralgia Sever pain in the course or distribution of the brachial nerve due to irritation or damage to the brachial nerve-Sciatica Pain in the distribution of sciatic nerve due to lateral disc protrusion on L4 andor L5 spinal nerve roots is called sciatica -Phantom limb pain Pain felt as though arising in an amputated limb is called phantom limb pain - Myalgia Pain in the muscles is known as myalgia 6-Myositis Bursitis and tendinitis

112

7-Muscle re-education and muscle strengthening

Contraindications1) Malignant tumours 2) Arterial disease the stimulatory effect of the current could produce embolus3) Deep Vein Thrombosis 4) Infective conditions 5) Artificial pacemakers on the heart 6) Pregnant Uterus 7) Condition of haemorrhage 8) Large open wounds these will cause concentration of the current and distortion of the IF field9) Dermatological conditions 10) Senile or confused patients 11) Advanced cardiac disease

Advantages of Interferential Current1-Large doses of the current can be produced without producing chemical burn2-The current can be localized more effectively in a specific area by careful positioning of the electrodes 3-Skin resistance is very much lowered hence there is no irritation of skin and thus interferential currents can be given for longer period of time 4-Interferential currents are used to treat deeper tissues as amplitude-modulated frequency is produced deep in the tissue 5-It can give sensory stimulation and motor stimulation 6-Interferential currents are used to treat larger area

Hazards (Dangers) of Interferential Current 1048599 BurnsBurns may be caused by -bare metal electrode against the skin-Insufficient moisture of the pad -Increased intensity with skin currents1048599Hematoma

113

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

7-Muscle re-education and muscle strengthening

Contraindications1) Malignant tumours 2) Arterial disease the stimulatory effect of the current could produce embolus3) Deep Vein Thrombosis 4) Infective conditions 5) Artificial pacemakers on the heart 6) Pregnant Uterus 7) Condition of haemorrhage 8) Large open wounds these will cause concentration of the current and distortion of the IF field9) Dermatological conditions 10) Senile or confused patients 11) Advanced cardiac disease

Advantages of Interferential Current1-Large doses of the current can be produced without producing chemical burn2-The current can be localized more effectively in a specific area by careful positioning of the electrodes 3-Skin resistance is very much lowered hence there is no irritation of skin and thus interferential currents can be given for longer period of time 4-Interferential currents are used to treat deeper tissues as amplitude-modulated frequency is produced deep in the tissue 5-It can give sensory stimulation and motor stimulation 6-Interferential currents are used to treat larger area

Hazards (Dangers) of Interferential Current 1048599 BurnsBurns may be caused by -bare metal electrode against the skin-Insufficient moisture of the pad -Increased intensity with skin currents1048599Hematoma

113

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

The vacuum pump tends to produce hematoma if the pressure is high

1048599 Increased pain 1048599 General malaise 1048599 Nausea 1048599 Vomiting 1048599 Dizziness Faintness 1048599 Migraine Headache 1048599 Neurological effectsStimulation of the autonomic nervous system may account for some of the general effects reported

Treatment parameters1-Amplitude-Modulated Frequency (AMF) AMF is defined as the difference between the frequencies

of the two medium-frequency currents which is produced in the tissues at the point where the two currents cross It is also known as the beat frequency

Amplitude of AMF is always higher than the amplitude of the two medium-frequency currents

For example Circuit A 4000 Hz medium Circuit B 3900 Hz frequency Beat Frequency 100 Hz ndash low frequency

AMF are of two types which are as follows a) Static AMF It is used for the treatment of localized or smaller areas

b) Dynamic or vector AMF

By varying the intensity of the second circuit relative to the constant intensity of the first it is possible to produce the dynamic AMF This vector can be of 45deg or 90deg It is used for the treatment of larger areas The vector system should only be selected if the site of lesion canrsquot be accurately localized

2-Frequency sweep

114

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

-In the sweep mode also called as the swing or frequency modulation the beat frequency changes automatically and regularly between some preset pair of frequencies over a specified time period-Thus the machine could be set to sweep for example between 20 and 80 Hz over a period of 6 sec and back over the next 6 sec-The pattern and timing of this modulation is usually adjustable and is sometimes called as the spectrum-Such an arrangement is claimed to reduce nerve adaptation and allow a stimulation of greater range of excitable tissues

3-Current Intensity The intensity of the current is dependent on the desired

physiological effect and the tissue to be stimulated In general the current should be adminustered at

sensory motor or noxious level Intensity should be slowly increased until the required

response has been reached

4-Duration of Treatment IFC must be applied for 10-20 minutes by session

5-Frequency of applying the treatment In most cases treatment every other day (3 time a

week) usually 12 session of application are made consecutively

Types of electrodes1-Carbon rubber Electrodes2-Vacuum Electrodes (suction cup)

are made from a vacuum unit plug into a rubber suction cup connected to a machine capable of producing a vacuum theyrsquore really plate electrodes kept in position by a vacuum instead of bandaging

the suction should not be constant because can be uncomfortable and causes bruising

wet sponges are placed in the cups and moisten the edges of the cups for better adherence

115

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Are excellent for treating large flat smooth areas for example the back

There may be anatomical areas that are less accessible and in these cases the suction option may be advantageous

The suction has been claimed to stimulate cutaneous nerves and cause vasodilatation

Figure (4) Vacuum electrodes

Electrode placement -Electrode positioning should ensure adequate coverage of the area for stimulation-Interferential currents may be produced either by applying the two medium frequency currents via four electrodes (quadripolar method) so that they intersect in the tissues or alternatively by mixing the two currents in the stimulator prior to application via two electrodes (pre-modulated or bipolar method)

Quadripolar technique The four electrodes are positioned around the target

treated area so that each channel runs perpendicular to the other and the current crosses at midpoint

The interference effect branch off at 45deg angle from the center of the treated area in the shape of a four leaf clover Tissues within this area receive the maximal treatment effect

116

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Placement of the electrodes should be such that a cross over effect is achieved in the desired area When the electrodes are properly positioned the stimulation should be felt only between the electrodes not under the electrodes

If the electrodes are not placed so that a crossover is achieved the physiological effects of interferential can not be achieved

Quadripolar interferential current is produced deep inside the tissues (AMF is produced endogenously) hence there is lowered skin impedance Thus it is used to treat larger areas

Bipolar Application Bipolar interferential current is produced inside the

machine (AMF is produced exogenously) hence there is increased skin impedance Thus it is used to treat localized area or smaller areas

This technique does not penetrate the tissues as deeply as quadripolar application and there tend to be more sensory sensation than with four pole technique although still less than with low frequency stimulation

A bipolar technique is preferable if a longitudinal zone requires stimulation rather than an isolated tissue area

When muscle contraction is the goal of treatment bipolar electrode placement is used

Adding another set of electrodes will create a three-dimensional flower effect called a stereodynamic effect and this allows for larger treatment area

117

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Principles of clinical application-Educate the patient about the interferential current -Check that there are no contraindications-Evaluate the sensations like touch pain and temperature-Position the patient comfortably with the area to be treated adequately supported exposed and relaxed-Prepare the skin to avoid resistance by washing and warming the skin and shaving the hair -accurately locate the site of lesion to be treated and mark the out the position of electrode placement- Optimal positioning of electrodes (Diagonal pattern) that the crossing points of the two currents lie above or around the affected part-Donrsquot place the electrodes on cuts abrasions open wounds or scratches-Soak the sponges or the pads in 1saline solution or in water The pads must be evenly moist and not dripping wet-Use equal size electrodes -Apply enough and comfortable vaccum during vaccum electrodes to prevent hematoma or ecchymosis Make sure that there is no discomfort or pinching sensation from the suction cup -Instruct the patient not to touch leads and apparatus during the treatment-connect the electrodes to the machine through the quadripolar lead unit if the quadripolar technique is used-Select the appropriate treatment parameters-The suitable frequency current should be given for different conditions-Select the base frequency and upper frequency the difference between them would give the spectrum-Always turn the intensity dial to zero before beginning the treatment-once the treatment is started increase the intensity until the desired result is produced-Ask the patient to tell you what he feels (prickling sensation occurring at the site of the lesion) if not it will be necessary to turn off the intensity and adjust the electrode position

118

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

-It may be necessary after 3 or 4 minutes to give the patient a little more intensity -Make sure that there is no Increase of the presenting symptoms of pain or

tenderness Feeling of heat or burning sensation Intense uncomfortable prickling sensation-After the treatment is terminated check the skin for any adverse reactions-Keep a full record of the treatment

Figure (6)Quadripolar application for the ankle joint

119

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Figure (7)Quadripolar application for the back with suction cup electrode

Figure (8)Quadripolar application for the back with carbon rubber electrode

RUSSION CURREN

120

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Content DefinitionTheoretical basisAdvantage of Russian CurrentClinical application

ObjectivesBy the end of this chapter the students should be able to Define Russian current and identify its characteristics Understand the theoretical basis for Russian current Discuss the advantages of applying Russian current Apply Russian to specific cases

Definition

Russion current is Medium-frequency polyphasic AC with frequency 2000 -10000 Hz fig (1)

Two basic waveforms (fixed intrapulse interval) o Sine wave o Square wave Pulse duration varies from 50 - 250 microsec Phase duration is half of the pulse duration o 25 - 125 microsec

Fig (1) Russian current with polyphyasic alternating current bull Current produced in burst mode with 50 duty cycle

121

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

bull To make intensity tolerable it is generated in 50-burst-per-second envelopes with an interburst interval of 10 msec ndash Increasing the bursts-per-second causes more

shortening in the muscle to take place

Fig (2) Russian current

bull In figure (2) Dark shaded area represents total currentbull Light shaded area indicates total current minus the inter

burst interval bull With burst mode total current is decreased thus allowing

for tolerance of greater current intensity bull As intensity increases more motor nerves are stimulated bull This increases the magnitude of contractionbull Russian current is a fast oscillating AC current therefore

as soon as the nerve re-polarizes it is stimulated againbull This maximizes the summation of muscle contraction

122

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Fig (3) An example of burst-modulated alternating current A minimum of 5 parameters must be specified in order to describe the waveform In this example the waves are sinusoidal the alternating current (AC) frequency is 1 kHz the bursts are rectangular the burst frequency is 50 Hz and the burst duration is 4 milliseconds

Theoretical basis- Maximum electrical stimulation can cause nearly all motor

units in a muscle to contract synchronously which cannot be achieved in voluntary contraction This would allow stronger muscle contractions to occur with electrical stimulation and hence greater muscle hypertrophy

- The frequency (pulse per second or in this case burst per second ie each 10 cosec burst contains 25 cycles of alternating current This would make the muscle respond with a twitch rather than a gradually increasing contraction Gradually increasing the numbers of bursts interrupts the mechanical relaxation cycle of the muscle and causes more shortening to take place

123

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to

Advantages of the current1- Because the current is fast oscillating alternating as soon

as the nerve repolarizes it is stimulated again producing a current that will maximally summate muscle contraction

2- The higher frequency of the current reduces the resistance to the current which make this current comfortable enough

3- The interburst interval allows tolerance of greater current intensity

4- Although it is medium frequency current the nerves are stimulated because it is interrupted to give a low frequency stimulation of 50 Hz

5- It can achieve muscle hypertrophy by using currents of high intensities producing maximum tolerable muscle contraction are given in spells of a few seconds separated by somewhat longer rest periods

Clinical applicationThis current can be applied in the usual way of electrical

stimulation used to stimulate muscle contraction using electrodes applied over the muscle belly (motor point) (See application of NEMS)

124

• By the end of this topic the students should be able to
• By the end of this chapter the students should be able to