What we have to know about Electrotherapy (measure, indicators and how does it work)

Electrotherapy made simple : https://www.youtube.com/watch?v=JAPU5iEfFVY

What is Electrotherapy ?

Electrotherapy is the use of electrical energy as a medical treatment. In medicine, the term electrotherapy can apply to a variety of treatments, including the use of electrical devices such as deep brain stimulators for neurological disease. When you feel nerve pain, an electrical signal is sent from a damaged nerve to your brain. Electrical stimulation for nerve pain works by sending out its own electrical impulses. These charges seem to interrupt or block the pain signals, reducing the pain you feel.

Electrotherapy units usually consist of a battery-powered device connected by wires to adhesive electrode pads which are placed on the skin. The electrode pads are sticky, so they will adhere to the skin. Once the electrodes are attached and the unit is turned on, a mild electric current is sent to the skin via the electrode. A number of newer electrotherapy devices bypass the wires, combining electrodes and battery power into a single unit that can be worn inconspicuously on the back, arm, leg, or elsewhere during work or other daily activities. A hand-held controller is used to adjust the level of stimulation.

You will need to use the TENS for about 30 minutes to reach maximum affect and it will last about 30 minutes after the TENS has been switched off. How long should a TENS machine be used for? The TENS machine can be used for as long as desired, typically 30 minutes up to 2 hours, several times a day if needed.

You can begin with one 15-minute therapy session. Repeat for another 15 minutes if needed. Use up to three times per day at a maximum. During each therapy, rate your pain before and after the session, 1 (low) to 10 (high) in order to gauge the true reduction of pain.

How does reduce pain?

The ‘Gate Control’ theory was first proposed in 1965. The main concept of this theory is that the brain can only pay attention to one stimulus (or message) at a time. When a painful stimulus causes a pain receptor (specialized cell that detects painful stimuli) to send a message to the brain via a ‘pain nerve’, the brain perceives that message as ‘pain’. Similarly, if a touch receptor is stimulated, a message is sent to the brain by a ‘touch nerve’ so that the brain perceives that message as ‘touch’ rather than pain. Experience tells us that even if we feel pain after hitting our elbow, the natural response is to rub the elbow and suddenly the pain is not as intense. This is because the ‘touch nerve’ is larger and sends its information to the brain faster so that the pain message never really gets recognized by the brain. This is the same mechanism by which mom’s kisses seem to help most of the pain that children experience! T.E.N.S. also works by this method. The appropriate electrical signal stimulates the touch receptors, and via a bit of fancy signaling in the spinal cord, the pain message is not acknowledged by the brain. It is important to recognize though, that this phenomenon doesn’t take away what is causing the pain and the pain relief doesn’t last forever. It simply provides a “rest from pain” (as in the following quote by John Dryde, (1631–1700) English poet and dramatist: "For all the happiness mankind can gain is not in pleasure, but in rest from pain") to permit you to move better and thus assist the body in getting the nutrition and activity that it needs to complete the healing of the painful area both at rest and during appropriate exercises. Pain relief usually does not continue beyond 6 hours. This time frame is similar to that of many common pain medications yet without the unwanted side-effects.

The other way that T.E.N.S. works to relieve pain is by stimulating the release of natural chemicals in the body which the body usually releases when there is injury or stress. The chemical substances released are known as endorphins and enkephalins. Endorphins are also naturally released by the body during prolonged exercise to produce the feeling of euphoria known as the “runner’s high”. Enkephalins are normally released with more intense but shorter duration exercise. The T.E.N.S. unit can be adjusted to selectively stimulate the release of either enkephalins or endorphins. A physical therapist can help you to select which settings of the T.E.N.S. would be most appropriate for your pain. The small electrical signal which is developed by the T.E.N.S. device is delivered to the body by specialized pads called electrodes. These electrodes are placed around the area of pain or on other areas of your body which are known to affect perception of pain. They are designed to ensure safe and effective treatment. It is important though that you ask your physical therapist to address with you the best ways to keep the electrodes working properly and optimally. Cleaning your electrodes and washing your skin (only where you are going to place the electrodes) with warm water before each treatment can prevent your skin from becoming irritated by the treatment. A physical therapist can also help you identify exactly where the electrodes should be placed on your body to optimize your pain relief.

Acute or Chronic Pain

T.E.N.S. can be used for either acute (recent or short-term) or chronic (long-term) pain. The settings on the T.E.N.S. unit can be adjusted to more effectively treat either type of pain. Again, a physical therapist can assess your pain and advise you on the settings that would be best for your type of pain. The two electrodes that attach to the TENS machine are called the anode and the cathode. The anode is positively charged, and sometimes represented by a + (plus) sign (sometimes coloured black). The cathode is negatively charged, and sometimes represented by a - (minus) sign (sometimes coloured red). The electrical current travels from the anode to the cathode, so the sensation is often stronger under the anode.

THREE basic modes of relieving pain with T.E.N.S.

CONTINUOUS (Constant or Normal)-

The standard T.E.N.S. treatment (also known as "conventional" or "high-frequency") is performed when the Pulse Rate is set to 60-100 pulses per second or more (in this method, rate, width (usually 200mcsec - and intensity settings are fully adjustable). It is thought that in this mode, pain relief is achieved through the gate control theory. The sensation produced with this setting can be described as a steady "buzzing" or "tingling" feeling between the electrodes. At this frequency the unit produces an electrical signal that is stronger than the pain signal that the body produces. Because the signal is perceived as stronger, it effectively blocks the pain signal from traveling along nerves to the brain. Most patients find that high-frequency treatments produce the quickest relief from pain, as well as providing hours of relief after the treatment if it is long enough .

BURST -

A "low-frequency" or "burst" type treatment is produced when the Pulse Rate setting on the T.E.N.S. unit is below 10 pulses per second ie. 2Hz (set manually) or at "burst" mode (automatic) (in this mode, width (often set at 200mcsec) and intensity settings are fully adjustable, however, the rate setting is not adjustable). Low-frequency treatments are done at an intensity that produces visible muscle twitching. The sensation at these settings is described as a "tapping" or "pulsating" feeling. The body reacts to this type of stimulation by releasing "endorphins" (pain-killing chemicals produced naturally in the body). These endorphins act as a chemical nerve block, effectively reducing pain by interrupting the flow of pain signals along the nerves. Patients find that this type of treatment sometimes takes longer to be effective (30 to 45 minutes), but once pain relief is experienced, it lasts for a longer period of time .

MODULATED -

Pulse width is automatically varied in a cyclic pattern at intervals of 6 seconds. The modulation range of pulse width varies from the control setting value to 40% less than that value. Rate, width and intensity are fully adjustable. Modulation of the T.E.N.S. output parameters (width, rate and amplitude) may prevent the nervous system from accommodating to the continuous mode of T.E.N.S., thus improving duration of pain relief.

Waveform

Russian Current

The Russian Current waveform delivers medium frequency in alternating pulses of energy. This makes it a popular waveform to use when there is a need to increase muscle strength and re-educate specific areas. The Russian current can also stimulate the relief of pain-relieving endorphins, increasing its versatility and applications.

Interferential Current (IFC)

Interferential Current (also referred to as IFC) is the waveform to use when treating chronic, post-surgical and post-trauma acute pain. IFC e-stim is non-invasive with minimal side effects. IFC delivers higher frequency energy so it crosses the skin barrier easier for deeper access into areas of pain, but also has improved tolerance.

Premodulated Current (Premod)

Premodulated Current, also referred to as “premod”, is similar to interferential current. The main difference is that with premod current, a single channel is used to mix the frequencies prior to before current reaches the patient. This makes it a good choice when treating smaller areas of the body like: elbows, ankles, feet, or hands.

Biphasic Current

"Biphasic" has two pulses of 2 different intensities. These alternate during treatment which makes it very versatile. Biphasic can be used for both acute and chronic problems for different goals including:

Strengthening & re-educating muscles
Improving blood circulation
Decreasing edema & swelling

High Voltage

High Voltage electrical stimulation is a monophasic waveform which uses polarity (positive or negative) to stimulate the tissue. This is a popular modality to aid in decreasing pain and swelling, reducing muscle spasms and facilitating wound healing.

Microcurrent

Microcurrent is also used for wound healing, utilizing micro-size, pulsing current. Because of its low intensity, microcurrent is the most tolerated waveform in electrotherapy.

Measure

Intensity: A dial allows the user to adjust the intensity of the electrical stimulation.

Frequency: The frequency refers to the number of electrical pulses per second. High-frequency (HF) pulses range from 80 to 120 cycles per second and may help manage acute pain. Low-frequency (LF) pulses range from 1 to 20 cycles per second and are suitable for the treatment of chronic pain.

Duration: The duration is the number of microseconds that the current enters the skin for during each pulse.