Many studies have found that TENS (transcutaneous electrical nerve stimulation) is useful in easing pain after surgery, as well as pain related to injuries, such as fractures and sprains according to the American Academy of Orthopaedic Surgeons. TENS may also be helpful for some chronic pain conditions, particularly low back pain. In 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.
How TENS Works
There are several ways TENS is thought to relieve pain:
Gate Control Theory. In order for you to feel pain, the sensation must travel through a “gate” to get to the brain. Normally, the pain is allowed to flow freely through the gate because it (pain) is the only sensation trying to get through. However, if the gate becomes flooded with another type of sensation (in this case, an electric current), the gate will reach capacity and no longer have room for the underlying pain sensation to get through.
Release of Endogenous Opiates. Some scientists believe that TENS works by forcing certain nerve cells to release more of the body’s natural pain killers called “endorphins.” This causes you to feel less pain.
Central Inhibitory Effect. TENS may also work by changing the way your brain perceives pain.
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