Electrical stimulation for pain control was used in ancient Rome, 63 A.D. It was reported by Scribonius Largus that pain was relieved by standing on an electrical fish at the seashore. From the 16th to 18th centuries various electrostatic devices were used for headaches and other pains, even Benjamin Franklin was a supporter of this method for pain relief.
Electrotherapy uses electrical signals to interfere with the transmission of neural pain signals into the brain. It effectively slows down or distracts the message from the nerve to the brain. From a therapy point of view, affecting one’s ‘Pain Gate’, whether in an acute or chronic pain episode, is crucial area of treatment and electrotherapy is a very useful resource where conventional medicines are not as affective. Electrotherapy can also involve the use of this electric current to speed tissue healing where tissue damage has also occurred.
Transcutaneous Electrical Nerve Stimulation (TENS)
TENS is widely used around the world for a variety of painful conditions such as;
Low back pain
Nerve related pain such as phantom pain
TENS Can Work In Two Ways
1/ On a high frequency, by selectively stimulating certain ‘non-pain’ nerve fibres to send signals to the brain that block other nerve signals carrying pain messages. High frequency stimulation, sometimes called “conventional”, is tolerable for hours, but the resultant pain relief lasts for a shorter period of time.
2/ Lower frequencies stimulate the production of endorphins, natural pain-relieving hormones – your own built-in pain management system. Low-frequency stimulation, sometimes called “acupuncture-like”, is more uncomfortable and tolerable for around 20-30 minutes, but the resultant pain relief lasts longer.
Unlike many pain-relieving drugs, TENS isn’t addictive and has few side-effects. Most people can use a TENS machine but it is unsuitable for:
-Patients with pacemakers and certain other types of heart disease.
-Unknown causes of pain.
-Certain body sites in pregnancy (other than in labour)
-Certain skin conditions
TENS users should experiment with various electrode placements. Electrodes can be placed over the painful area, surrounding the painful area, over the nerve supplying the painful area, or even on the opposite side of the body. TENS users need to try the unit for several days with several electrode placements prior to deciding if it will be useful. A home trial for several days to weeks is preferable.
Here at Peak Chiropractic we also use an electrotherapy modality called interferential therapy (IFT). It is essentially a much deeper form of TENS. It utilises two high frequency currents which are slightly out of phase, and are passed through the skin at the same time where they are set up so that their paths cross and simply interfere with each other. This interference gives way to a beat frequency which has the characteristics of low frequency stimulation deep under the skin.
It is administered by a physiotherapist and involves the placement of damp sponges on the body which deliver a mild current similar to the sensation of pins and needles. Manipulation of the current allows the therapist to target the correct structure and to treat.
There are 4 main clinical applications for which IFT has been found to be effective:
Pain relief (in a similar fashion to TENS)
Muscle stimulation – prevent muscle wastage, re-education, maintain range of motion
Increased local blood flow
Reduction of oedema