What is TENS?
Transcutaneous Electrical Nerve Stimulation (TENS or TNS) 
​TENS is considered a non-invasive physical therapy using a low-voltage electrical current to reduce inflammation, increase circulation, and help with pain. TENS devices are like a small, portable mini massager about the size of a portable radio or iPod. Many units are small enough to fit inside your pocket.

How It Works

  • Mild electric current is produced by a TENS device or unit. The purpose is to stimulate the nerves for therapeutic purposes, such as pain relief.
  • TENS, by definition, is transcutaneously applied currents. It works by sending stimulating pulses across the surface of the skin and along the nerve strands for pain relief and muscle relaxation.
  • The unit is usually connected to the skin using two or more electrodes. Stick-on pads are placed on the skin--nothing pierces the skin. A soothing vibration then passes through the skin by electrical stimulation.
  • A typical battery-operated TENS unit is able to modulate pulse width, frequency and intensity.

How Do You Control TENS?

​A TENS unit delivers an electronic pulse to the nerve endings. This in turn makes the muscles contract, increasing circulation. Using a TENS portable unit is a great way to fight pain and inflammation because it is designed to send the flow of blood directly to the affected area, thereby increasing circulation.
You control the amount of electrical stimulation you receive while wearing your portable TENS unit. There is a control switch that you can use to adjust the frequency of the electronic wavelengths that the unit sends out.
For example, you can set the device so that it sends out a constant flow of current or so that it delivers a quick burst of current, in addition to various intensity levels. A medical professional can help determine the settings that will work best for your specific needs.

History of TEN

​Electrical stimulation to relieve pain was known as far back as ancient Roman, 63 A.D. Benjamin Franklin was aware of the benefits and was a proponent of this method for pain relief. In the 19th century there was a device called the electreat that was used for pain control and other treatments, but it was not portable and there was limited control of the stimulus.
The first modern, patient-wearable TENS was patented in the United States in 1974. It was initially used for testing the tolerance of chronic pain patients to electrical stimulation before surgical intervention. Although intended only for testing tolerance to electrical stimulation, many of the patients reported they received much relief from the TENS itself. A number of companies began manufacturing TENS units. Today, there are small and large units, as well as portable belt-type devices.

Who Shouldn’t Use TENS

While there are very few side effects associated with the TENS unit, there are people who should not use it, as it could complicate a medical condition or cause extremely hazardous effects. People who should not use this device include:
  • Those who have a cardiac pacemaker in place.
  • Individuals who have been diagnosed with a malignancy of any kind.
  • People who have certain types of heart disease.
  • Anyone who has epilepsy.
  • Women are pregnant, unless otherwise directed by a doctor.
  • Individuals who have Alzheimer’s Disease, dementia, or other cognitive problems as the unit may not be used properly.

How to Use a TENS Device

​Electrodes run from the TENS device and are attached to your body in strategic spots via electrode pads. Once the electrodes are in place, the device is turned on, it sends out an electronic pulse. When the current sent from the TENS unit is delivered to the body, many people have reported that they feel a reduction in the amount of pain they experience. A TENS device is simple to use, convenient, portable, and can help you to enjoy the benefits of physical therapy at your home, work, or even while traveling. Many still run on a 9 volt or 3 AAA batteries, but some of the more modern units have a rechargeable lithium battery that only needs to be recharged every six to eight weeks.

Who Can Benefit from TENS

​There are a variety of muscle, bone, and joint conditions that the TENS unit can be used to treat. Some of the conditions that the device is most commonly used to treat include:
  • Back pain
  • Neck pain
  • Osteoarthritis
  • Fibromyalgia
  • Bursitis
  • Tendinitis
  • Muscle tension and knots
  • Inflammation
The TENS mini massager has been used to treat a variety of conditions that cause acute and chronic pain, including the acute pain that is associated with labor and childbirth, and the chronic pain that cancer patients can experience.

Safety Practices

TENS is generally thought to be safe. Though this form of electrostimulation has proven to provide relief for many people, there is a small chance that you could experience negative effects if it is not used properly.
  • Do not use over or near the eyes, due to the risk of increasing intraocular pressure.
  • Do not use on the front of the neck due to the risk of acute hypotension
  • Do not place on broken skin areas or wounds, although it can be placed around wounds.
  • Do not place directly over the spinal column
  • Do not use TENS in the shower or bathtub.