TENS, or transcutaneous electrical nerve stimulation, is a back pain treatment that uses low voltage electric current to relieve pain.TENS is typically done with a TENS unit, a small battery-operated device. The device can be hooked to a belt and is connected to two electrodes. The electrodes carry an electric current from the TENS machine to the skin.There is little research to support how -- or even if -- TENS really works. Its use dates back to the 1960s with the introduction of the gate control theory of pain. According to the theory, stimulating nerves closes a "gate" mechanism in the...…TENS, or transcutaneous electrical nerve stimulation, is a back pain treatment that uses low voltage electric current to relieve pain.TENS is typically done with a TENS unit, a small battery-operated device. The device can be hooked to a belt and is connected to two electrodes. The electrodes carry an electric current from the TENS machine to the skin.There is little research to support how -- or even if -- TENS really works. Its use dates back to the 1960s with the introduction of the gate control theory of pain. According to the theory, stimulating nerves closes a "gate" mechanism in the...WW…