Hundreds of thousands of people suffer from both acute and chronic pain every single day. Many rely on prescription medications to alleviate the discomfort, while others are constantly searching for a proper treatment that doesn’t cost thousands. TENS, also known as transcutaneous electrical nerve stimulation, is a noninvasive pain treatment for both chronic and acute pain.
How does a TENS unit work?
The TENS unit is a small handheld device that sends electric currents to the skin through the means of adhesive pads. Different settings allow you to control the intensity of the electric current as well as the frequency and duration of each pulse. The electrodes are placed on particular points of the body that correspond with where the patient is experiencing pain. When turned on, the TENS unit sends electrical currents through the electrodes and into the skin. This stimulates specific nerve pathways that produce a tingling sensation to reduce the perception of pain.
How we perceive pain
When we pull a muscle, stub a toe, or pinch a nerve, pain signals go to the brain. A pain signal travels up the peripheral nerve to the spinal cord, which releases neurotransmitters. These signals go up the spinal cord into the brain. In the brain, the signals transmit to the thalamus. This is the part of the brain that organizes signals and sends them to the proper areas of the brain. The thalamus then sends these pain signals to the frontal cortex (which is in charge of thinking), the limbic system (which is responsible for emotions), and the somatosensory cortex (which causes physical sensation). All of this happens at lightning speed, and you perceive the pain in a certain area of the body while reacting emotionally. 1
The science behind the treatment
We know that TENS units work by sending electric currents through the skin and into nerve pathways. The science behind why this is effective is a bit more complicated. There are two different theories behind how TENS treatment blocks the perception of pain.
The first is known as the Gate Control Theory. This theory suggests that there is a particular neural mechanism in the spinal cord that can either ‘open’ or ‘close’ the flow of pain signals to the brain. Whether the gate is open, closed, or partially open depends on the type of signals that it receives from the brain. This gate can effectively change the perception of pain, reducing it partially or even completely. The frequencies emitted from the TENS unit interfere with the transmission of pain messages at the spinal cord level, helping to block their transmission to the brain.
The second theory concerns the release of endorphins. It is thought that electrical currents can stimulate the production of endorphins within the body. Endorphins are the body’s natural pain relievers, and can also help block pain messages from reaching the brain. Endorphins can also help boost your mood, alleviating any stress and anxiety that stems from the pain. This is essentially how pain-relieving medications work in the body, yet without the negative side effects and dependency. 2
The invention of the TENS unit
Melzack and Wall coined the Gate Control Theory in 1965. When the research was published, it was acknowledged that electricity could play an important part in pain reduction. The first practical test of this theory was actually the development of the first TENS unit.
This isn’t the first time electricity has altered pain signals. The application of electricity to treat pain dates back thousands of years. The Ancient Egyptians, Greeks, and Romans used electric eels to alleviate the pain of headaches and gout. In the 19th century, physicians used electrotherapy for dental, psychiatric, neurological and gynecological procedures. They reevaluated this controversial form of treatment in the 20th century, leading to the types of modern electrotherapy we have today. These include TENS, PENS (percutaneous electrical nerve stimulation) and SCS (spinal cord stimulation). 3
TENS is effective for arthritis, period pain, endometriosis, knee pain, back pain, neck pain, sports injuries, and other types of discomfort. You can use the TENS unit at home for as long as you need to alleviate pain in a non-invasive way. It is an easy, effective treatment that minimizes the need for prescription drugs or expensive procedures.