TENS is an abbreviation for transcutaneous electrical nerve stimulation. This is a method of conducting electrical stimulation through the skin to the nerves for the purpose of controlling pain. It is a small device that provides this action using two or more electrodes attached to the skin with adhesive backing. The electric impulse is battery powered. The intensity and frequency of the current differ depending on the condition being treated.
There are two types of Tens machines on the market, one for consumers with preset ranges and a professional version that has no preset range allowing the frequency and intensity to be set by the practitioner for a particular patient and condition.
The use of electricity for medicinal purposes is not a new theory. In Egypt there are ancient stone carvings in which electric fish are depicted being used to treat painful ailments. Electrogenic torpedo fish were used in the times of ancient Greece for headache and arthritis pain relief. In early American history, Benjamin Franklin was proactive in the support of electricity to treat medical ailments.
The placement of the electrodes, frequency and intensity are key factors in optimizing the effects of stimulation. There is much speculation on how the tens machine works, none of which have been clearly proven with scientific research. It is thought to interfere with the nerves perception of pain or interrupt nerve pathways. There are theories that it alters natural chemicals that determine the way pain is transmitted or perceived by the body such as endorphins, encephalins or opioids. Another explanation is that it has effects on the flow of vital energy, a theory commonly used to promote acupuncture.
Much research has been done to determine the many uses of a Tens Machine. The studies are reported to show some success but more research is needed before the medical communities will offer firm conclusions. There has been testing with success in treating pain of headaches, backache and menstruation. Other studies state that tens can help joint disorders and heart disease. In these studies it is stated that the long term benefits are not clear. There was some research that reports that TENS improved some Alzheimer symptoms like memory, mood and cycles of rest and activity. This therapy has been studied for use in treating carpal tunnel syndrome and soft tissue or tendon injuries as well.