> There is evidence to support the operation of TENS units. Search for "Gate
> control theory". This theory also explains why acupuncture, some pain
> killers, endorphins and adrenaline also have a pain numbing effect. Think
> transistors.. and the gate either allows signals through or not, both
> chemical and electrical stimulus can close the gate so signals either
don't
> pass through the nervous system to the brain, or pass at a much reduced
> level.

Certainly a lot of debate re TENS effectiveness -

Theories of operation        http://www.d-med.com/up/html/theory.html

Musings                    http://www.veritymedical.co.uk/modes/TENS.htm
Includes some clinical references

Summary of findings of formal trial for use with lower back pain.
Concludes it doesn't work in this application.

        http://www.update-software.com/ccweb/cochrane/revabstr/ab003008.htm

Same people. Clinical trials for treatment of Osteo Arthritis.
Concludes it does work in this application.

        http://www.update-software.com/ccweb/cochrane/revabstr/ab002823.htm

Does TENS work ?
Worth reading

            http://www.jr2.ox.ac.uk/bandolier/band37/b37-3.html




            RM

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