In transcutaneous electrical nerve stimulation (TENS) a special device transmits low-level electrical charges into the area of the body that is in pain.
A TENS system consists of a small, battery-powered machine connected by wires to a pair of electrodes. The two electrodes are connected to your skin near the source of pain or at a pressure point. A mild electrical current travels through your skin and along your nerve fibers which may cause a warm, tingling sensation. A typical TENS session lasts anywhere from 5 to 15 minutes.
Many studies have found that TENS is useful in easing pain after surgery, as well as pain related to injuries, such as fractures and sprains. TENS may also be helpful for some chronic pain conditions, particularly low back pain. TENS is generally considered safe. However, its routine use is not recommended.
There is also an acupuncture version of TENS in which the electrical impulses are sent through acupuncture needles instead of electrode pads. This form of TENS is called “electro-acupuncture” or percutaneous electrical nerve stimulation (PENS).