Q: "I have chronic back pain. My doctor suggests I try using a TENS unit to help control the pain. I have a TENS prescription but don't know which unit to choose. I don't understand how a TENS works or why one unit might be better than another one. Please help. Thanks. Paula."
Answer: TENS stands for Transcutaneous Electrical Nerve Stimulation, i.e. nerves are stimulated using low levels of electricity via electrode pads coated with a conductivity gel placed on your skin. TENS decreases pain by transmitting painless electrical impulses via those electrodes. The electrical signals travel from the TENS unit through wires to the electrodes. The signal then passes to the nerves under the skin. These nerves take messages to the brain about what they feel, such as touch, warmth, pressure, and pain. TENS signals can replace the message of pain on these nerves with a tingling sensation. This changes your impression of the pain.The TENS signals may also increase the amount of endorphins (end-or-fins) in your body. Endorphins are a pain-relieving chemical made naturally by your body.
All units come with 4 electrode wires and 4 electrode pads. The analog units are less expensive, using dials to turn up the intensity of the stimulation, set the duration, etc. The Economy Lumiscope Unit has three modes Standard, Bust and Modulation and is controlled by turning dials. The Deluxe Analog Unit is similar with dial controls but has a wider range of stimulation. Both analog units can have the settings changed by accidentally moving against something if the unit is attached to your waistband, for example. (And that can be a huge "shock" as I found out about 10 years ago when I moved the wrong way in an airplane seat when wearing the analog deluxe unit.) The Grafco Digital TENS has a memory, LCD read-out, dual channels and more accurate in the amount of stimulation one receives.
Where the electrodes are placed depends on the type and location of your pain. The electrodes may be placed to "cover" or "surround" the painful area. This works very well with muscle pain, spasms, or painful joints as in arthritis. Or, the electrodes may be placed to "capture" the pain as with the pain of a surgery incision (cut). The electrodes may be put between an injured nerve and the brain when a nerve has been hurt.
Placement of electrodes is usually at motor, trigger or acupuncture points. These are high tissue conductivity points that can differ in location and theory of use yet their uses as electrode sites is identical. The easiest technique involves placing one pad directly over the point and completing the circuit by placing the second pad on some area on the affected side. This second electrode site can be within a nerve zone, or a master point located between the thumb and the forefinger on the dorsaI If the electrodes are put in the wrong place your pain may not be lessened. The pain could even get worse if the electrodes are placed incorrectly. The electrodes should never be put near the eyes. The electrodes should also not be put over the nerves from the neck to the throat or brain. A physical therapist or physician can actually mark the best points using a magic marker on your skin so you know where to place the electrodes initially.
Usually TENS treatment lasts 3 to 5 days. It may be used around the clock for some pain, like "phantom limb" pain. This is pain you feel in your foot or hand after that limb was amputated (cut off). Or, the TENS treatment may be used for 3 to 4 hours a day for pain like arthritis. You may be able to give yourself TENS treatments at home. If this is so, caregivers will teach you how to put on the electrodes and control the TENS unit.
I recommend that you discuss your needs with your physical therapist or physician. Then choose a unit based upon the amplitude and intensity that you need, whether you prefer to have the programmed intensity ramp up automatically rather than changing it manually, and your budget. Fax, mail or email your prescription as Federal Law requires for sale to other than hospitals and physicians if you living in the USA.
Thanks for your question. Among our customers for these units are those with multiple sclerosis, sciatica and back pain. We wish you the best. Let us know if we can help further