Introduction to Electrotherapy
In this article we are going to discuss about Electrotherapy types, benefits, side effects and its contraindications. Also we are going to talk about different types of electrotherapy machine and their use according to different health conditions.
In electrotherapy electric currents are used to produce therapeutic benefits and physiological changes at tissue level by making alterations to cell metabolism.
Electrotherapy is mainly used to treat different types of disorders and diseases of human body with the help of electrically operated machines.
Those electrotherapy machines uses currents are:-
Directly applied electric currents are–
- Low frequency current.
- Medium frequency current.
- High frequency current.
Indirectly applied Currents are-
- Cryotherapy unit.
- Hydrocollator etc.
There are different types of physiological and chemical changes produces in our tissues, when we use different types of electrical modalities for therapeutic purpose.
According to their frequency, electrotherapy machines are mainly divided. Which are :
- Low frequency current – 1 Hz to 1000 Hz
- Medium frequency current – 1000 Hz to 10,000 Hz
- High frequency current – more then 10,000 Hz
Low frequency currents
- Faradic current
- Electro acupuncture
TENS – Transcutaneous electrical nerve stimulation
TENS is one of the highly used machine by physiotherapist in clinics, hospitals and home visits to reduce pain of any body part. This type of electrotherapy technique is very simple in use and non-invasive.
By this the electrical currents are given through the skin for activation of peripheral nerves. It is mainly used for acute and chronic pain reduction like pain in cancer like disease and other painful conditions.
- Pulse duration – 50-200 Micro second
- Frequency – 1 – 120 Hz
- Max peak current – 50 – 100 mA
Portable TENS devices are also available now, in those portable TENS devices pulsed current is produced by battery. which we can easily carry in our pocket, current from those devices are delivered through skin by electrode pads.
Types of TENS
- CONVENTIONAL TENS
- AL-TENS also called LOW TENS
- BRIEF TENS
- BURST TENS
Benefits of TENS
- Neuropathic pain
- Acute pain due to dysmenorrhea (painful menstruation)
- Orofacial pain ( pain felt in the mouth, jaws and the face )
- Angina pectoris ( pain in left side upper limb or upper extremitie )
- Postoperative pain
- Obstetrics pain ( Pain during childbirth )
- Arthritic pain
- Musculoskeletal pain
- Back pain
HVPGS – High voltage pulsed galvanic stimulation
High voltage pulsed galvanic stimulation is applied upto 500 volts. In this type of current twin pulses waveform present with instantaneous rise with exponential fall.
The setting of peak voltage is set according to patients safety because it may cause breakdown of skin and results in burn.
Benefits of HVPGS
For wound healing – HVPGS is used for wound healing and ulcers like problem in body. In this process there is increase in rate of DNA synthesis and protein synthesis.
Pain relief – It is used for all kind of pain relief i.e. Acute pain, Chronic pain, Neurogenic pain etc. Pain relief is done by pain gate control theory. Used in painful conditions like patellofemoral joint pain, myofascial pain etc…
Edema reduction – HVPGS helps in Edema reduction by continuous muscle contraction and relaxation which increases blood flow in muscle and tissue, helps in clearing edema.
Muscle stimulation – This type of current is also used for stimulation of innervated muscles. HVPGS used in muscle disuse atrophy ( caused by not using your muscles enough, results in muscles breakdown which causes them to decrease in size and strength ), other use is muscle strengthening.
Other electrotherapy type is Faradic current, it is a low frequency current, this type of electrotherapy current used for stimulation of innervated muscles. It is interrupted direct current. This type of current acts directly on nerve fiber with intact nerve supply.
- Frequency – 30Hz to 70Hz
- Pulse duration – 1ms or less
Benefits of faradic current
Facilities muscle contraction – When muscle is unable to contract due to pain or injury, then we use faradic current. It initiate and facilities voluntary contraction of muscle.
Training of new muscle actions – Faradic current is used for training of new muscle action after surgeries, muscles are stimulated with this current so new muscle action is produced.
Nerve injury – It also helps in nerve injuries, the sensory nerve stimulates downward going nerve while motor nerve stimulates upward going nerve.
Movement reeducation – Movement education or reeducation is done by faradic current by giving stimulation when patient not be able to do normal voluntary movement due to lack of sensation.
Improves lymphatic and venous drainage – This current increases lymphatic and venous drainage by muscle contraction and joint movement. The process of increasing drainage is most effective by faradism under pressure technique, in this technique the limb is tie with elastic crep bandage with decreasing pressure from distal to proximal without gap between bandage.
Electroacupuncture is new type of acupuncture method, in this Electrotherapy types electricity is used to increase the benefit of the treatment.
In this technique small needles are put in body part after that electrodes are connected to those needles, which transfers electric current. Electro acupuncture covers large area of body part then other acupuncture, this is one of the good thing about this technique.
Benefits of Electroacupuncture
- tinnitus -( ringing or buzzing in the ears )
- Nausea due to chemotherapy
Medium frequency current
- Interferential current
- Russian current
Interferential current is application of two medium frequency alternating current which penetrates through the skin, for therapeutic purpose to treat pain in deeper tissues and contraction of muscles and tissues.
For example one current is at 6000 Hz and other current is at 5950 Hz, so the beat frequency of both current will be 50 Hz.
Benefits of Interferential current
- Relief from edema
- Relief from pain
- Increasing muscle strength
- Used for pelvic floor training
Russian current produces a strong muscular contraction and greater muscular hypertrophy, this current is also called Tone burst current.
Current consist of burst duration of 10ms with 0.2ms pulse duration, which is seperated by 10ms when no current flows so it produces 50 bursts/second.
Electrodes are placed over muscle belly, parallel to the muscle fibres direction. This current has 2500 Hz uniform alternating medium frequency current. This current has burst modulation at 50 Hz frequency with fifty percent duty cycle.
Benefits of Russian current
- Reduces edema
- Relief muscle spasm
- Back pain
- Increase muscle strength
High frequency current
High frequency current alternate soo fast that it dose not stimulates the motor or sensory nerves, generally in this Electrotherapy types , current is used to produce heating effect inside tissue.
( Diathermy means electrically insulated heat )
SWD – Short wave diathermy
SWD is the application of alternating current at frequency of 27.12 MHz and with a wavelength of 11.06 meter for production of heat inside body tissue. In this process high electromagnetic energy passes through body tissue which produces heat.
The electric or magnetic field is produced by SWD machine, which alternates at high-frequency.
Short wave diathermy machines are available at both 250 watts and 500 watts models, those machines are operated at 220 volt single phase electric supply.
Benefits of SWD – Short wave diathermy
- Relief of pain
- In bacteria infection
- Decrease inflammation
- Helpful in traumatic conditions
- Induces muscle relaxation
PSWD – PULSED SHORT WAVE DIATHERMY
Pulsed short wave diathermy is the application of pulsed electromagnetic energy in short bursts. PSWD also operates at same frequency as SWD that is 27.12 MHz. In the machine the ON time is shorter then the OFF time so the power that delivers to the patient is relatively low.
- Pulse repetition rate – 15 Hz to 800 Hz
- Pulse duration – ON phase duration, 25 microsecond to 400 microsecond
- Power – 100 W to 1000 W
Benefits of PSWD
- Fast healing of bone by enhancing osteogenesis
- Stretching of soft tissue
- Healing of nerve
- Decrease in pain
- Management of edema
- Acute soft tissue injury
- Healing of wound
LWD – LONG WAVE DIATHERMY
Long wave diathermy was highly used before in past but now it is replaced by SWD. It is called long wave diathermy because it has relatively long wavelength, it has frequency of 10⁶ Hz and a wavelength of 300 metres.
Now this type of electrotherapy modality is again start using by therapist at present due to its good and superior effect of pain relief as compared to SWD. The treatment with PSWD is more accurate and penetrative which gives faster relief to patients as compared to other modalities.
- Wavelength – 300 meters
- Frequency – 1 MHz
- Power – 25 watts
Benefits of LWD
- Deeper penetration
- Reduces pain
- Improve mobility
- Penetrates upto 4 cm
- Improve circulation
- Dose not interfere with other equipments
- Dose not irritate bony tissues
- Consumes less electricity
MWD – MICRO WAVE DIATHERMY
MWD Microwave diathermy lies between infrared waves and short waves, this is one type of electromagnetic radiation. It is also called decimeter waves because their wavelength is between 1 cm to 100 cm.
The microwave extends wavelength between 1 meter to 1 mm. In medical uses, its frequency are as follow:
- Frequency 2450 MHz ( at Wavelength of 12.2 cm )
- Frequency 915 MHz ( at Wavelength of 32.8 cm )
- Frequency 434 MHz ( at Wavelength of 69.1 cm )
Microwave diathermy dose not penetrates asdeep as short wave diathermy, the energy is first absorbed at skin surface of body then remaining part penetrates and absorbed in deeper tissues. Microwave produces therapeutic tissue heating to treat musculoskeletal disorders.
Benefits of MWD – Microwave diathermy
- Improve function at different types of arthritic condition
- Resolve inflammation
- Reduces pain
- Sports injuries
- Traumatic condition
Side effects of electrotherapy
As we know everything has two different sides one good and one bad, likewise electrotherapy has also some side effects and contraindications.
Electrotherapy has only few side-effects , let’s know about some side effects of electrotherapy point wise.
- In some rare cases it causes allergic reaction on patients skin, which causes irritation on skin.
- Electrotherapy can’t be applied to a physical issue that is bleeding.
- It can’t be applied to cancerous tissue.
- It cannot be used at over sensitive body part.
- It can’t be applied to infected body part.
- We cannot use this therapy to pregnant womens abdomen or back area.
Contraindications of electrotherapy
- It should not applied to infected or cancerous tissue
- It should not applied over pregnant uterus
- Very small children’s should not be treated with this therapy
- Electrodes should not be placed over anterior of neck
- It should not be applied over pacemaker
We hope that you found all the answers of your questions that what is electrotherapy, its benefits, electrotherapy types, its side-effects and its contraindications. If you still have any doubt in any thing then please feel free to contact us. If you are interested in this field or want to know more about Physiotherapy then please read all our physiotherapy related articles, we mention almost every thing related to physical therapy.