TENS Has Potential

Transcutaneous electrical nerve stimulation (TENS) currently is one of the most commonly used forms of electroanalgesia--the treatment of pain via electrical stimulation. Hundreds of clinical reports have been released on the efficacy of the use of TENS for back pain, visceral pain, etc., along with various types of arthritic pain. An ongoing debate about TENS has brought the degree to which TENS is more effective than placebo in reducing pain into question.

The proposed mechanism of the analgesia produced by TENS deals with a theory proposed by Melzack and Wall over forty years ago. Essentially, neurons called C fibers send the electrochemical signal for pain to the thalamus and cortex. In the case of arthritis, these C fibers continuously send the pain signal. With TENS, it is proposed that the proper form of electrical stimulation will survive as an impulse to incite the fibers to stop "firing." In addition, tens is said to stimulate the production of endorphins, natural pain-relief hormones secreted by the body.

A TENS unit itself consists of one or more electric signal generators, a battery, and a set of electrodes. The units are small and programmable, and the generators can deliver trains of stimuli with variable current strengths, pulse rates, and pulse widths. Electrodes are attached to the surface of the skin over or near the area where you are experiencing pain. A TENS session usually lasts for less than a half hour, and used several times a day.

The previously mentioned clinical reports on the use of TENS produced a variety of results, ranging from very positive to negative effectiveness. Currently, there is an overall consensus favoring the use of TENS, with authorities differing on its value in different clinical situations. Generally speaking, TENS provides initial relief of pain in 70-80 percent of patients, but the success rate decreases significantly after a few months.

TENS units should only be used according to the directions provided by your doctor.

Article References
Transcutaneous electrical nerve stimulation (TENS) for the treatment of rheumatoid arthritis in the hand (Cochrane Review), site accessed on 1/16/2006

eMedicine--TENS, site accessed on 1/17/06