The below post was made on Dec. 31, 2007 in response to article, "The Truth Behind Electric Waves For Pain Relief", on one of the chronic pain blogs of MedFaxx.
The author makes some interesting points here but the generalizations being made are without foundation or merit.
The title insertion of "electric waves" is illustrative of the misunderstanding of the subject matter. I'm not criticizing the author but pointing out that many arguments are made without knowledge of the way electricity interacts with the human body.
The historic context of "electric waves" is one of the use of direct current, ie. the early Biblical references of "eels" and putting one's body part in the water for the shock effect which for some caused short/midterm pain relief. DC ( direct current ) is the form of electric waves upon which the historical context is discussed. Galvani used DC to stimulate frog legs to "jump",even after death, is one of the classics of "electric waves".
There is a plethora of research articles, most not double blind due to the sensory effect of electrical stimulation being felt, that have supported the use of E-stim for pain relief, be it chronic or acute. HCFA - Medicare, most major insurance companies, state funded health care ( Medicaid , Worker's comp programs- local and national, all relied upon the research to make their decisions to cover the cost of tens and it's associated supplies as an effective, cost efficient method of pain control for chronic pain and in some cases for acute pain if used for post surgical applications.
One of the most effective forms of electrotherapy , note I say electrotherapy, not electric waves, is the use of interferential therapy both clinically and now as an outpatient therapy. Electricity, interferential, is merely agents of the electromagnetic spectrum of which there are literally billions of combinations. Interferential is the use of 8,000+ pulses of electricity ( AC- alternatng current the difference in discussing electrotherapy now and in the past ) administered transcutaneously per second. This compares to "tens" which is generally 150 pulses per second.
Interferential ( IF) gives immediate results and also tends to have long term carryover relief for the patient. Carryover is the time one has significant pain relief prior to needing another treatment. Now having said that Interferential is still regarded, 60 years later, as "experimental" by HCFA ( Medicare) but is the most used form of electrotherapy for pain relief. TENS is not regarded as experimental nor is the efficicacy of the modality in question.