Electrical nerve stimulation history
For several thousand years, people have recognized that electrical stimulation can have an impact on pain. Hippocrates, the father of medicine, is said to have used electric fish to cause numbness, and a report of gout being “cured” by accidental contact with a fish called an electric ray dates back to the first century. Later reports also described pain resolution that occurred when similar types of “electric” fish were placed on afflicted body parts.
It wasn't until the 18th century when a more formal device to deliver electricity to decrease pain was created. Although initially developed in Europe, Benjamin Franklin is credited with reforming the original electric condenser, which was used to shock patients in an effort to treat various ailments.
What is a transcutaneous electrical nerve stimulation (TENS) unit?
Today, transcutaneous electrical nerve stimulation units, or TENS units, are commonly used to treat many types of pain, including chronic back and neck pain. Unlike the early devices, where the amount of electricity delivered might vary, TENS units supply a controlled electrical current to stimulate nerve endings through surface electrodes, which are placed over the affected region.