Transcutaneous Electrical Nerve Stimulation (TENS) units are small, battery-powered devices designed to deliver mild electrical currents through the skin. These currents stimulate nerves to help manage pain. Plantar fasciitis is a common condition characterized by pain in the heel and bottom of the foot, arising from a disorder of the plantar fascia, the connective tissue supporting the foot’s arch. This article explores how TENS units may offer relief for individuals experiencing plantar fasciitis pain.
How TENS Units Work
TENS units alleviate pain through two primary mechanisms. One theory is the gate control theory of pain, which suggests the spinal cord acts as a “gate” controlling pain signals to the brain. Electrical impulses from a TENS unit stimulate large sensory nerve fibers, transmitting non-painful sensations. This stimulation effectively “closes” the pain gate, reducing pain signals to the brain and decreasing pain perception.
The second mechanism involves the release of endorphins, the body’s natural painkillers. TENS therapy stimulates the production and release of these chemicals. Endorphins interact with opioid receptors in the brain and spinal cord, reducing pain intensity and promoting well-being. This contributes to the analgesic outcome of TENS treatment.
TENS and Plantar Fasciitis Pain Relief
Plantar fasciitis involves discomfort or inflammation of the plantar fascia, a thick band of tissue running along the bottom of the foot from the heel bone to the toes. This condition commonly causes stabbing pain, often most severe with the first steps in the morning or after periods of rest. The tension and stress on the plantar fascia can lead to small tears and irritation.
TENS units can specifically address the pain associated with plantar fasciitis by leveraging their pain-relieving mechanisms. The electrical impulses stimulate sensory nerves in the foot, effectively interfering with the transmission of pain signals from the affected plantar fascia to the brain. This “overloading” of the nervous system reduces the brain’s perception of pain in the heel and arch area.
TENS therapy can also enhance blood circulation to the plantar fascia. Improved blood flow delivers more oxygen and nutrients to inflamed tissues, potentially aiding healing and reducing inflammation. This contributes to pain relief for plantar fasciitis.
Using a TENS Unit for Plantar Fasciitis
Using a TENS unit for plantar fasciitis involves specific electrode placement and settings for optimal results. Generally, electrodes should be placed on the bottom of the foot, near the area of pain. One common approach is to place one pad on the center of the heel, where the plantar fascia originates, and the second pad on the arch of the foot, allowing the current to flow through the inflamed tissue. Alternatively, some individuals may find relief by placing one pad on the bottom of the affected foot and the other on the calf or side of the foot, especially if pain extends into the calves.
When initiating therapy, begin with the lowest intensity setting and gradually increase it until a strong but comfortable tingling sensation is felt, avoiding any intensity that causes pain. For chronic pain, lower frequencies (around 2-10 Hz) are used, while higher frequencies (50-120 Hz) are for acute pain. Typical session durations range from 20 to 30 minutes, and treatment can be repeated several times daily, such as in the morning, after prolonged standing, or before bed.
Important Considerations
A TENS unit serves as a pain management tool and does not offer a cure for plantar fasciitis. While it provides temporary relief, it is most effective when used as part of a broader treatment plan. This plan may include stretching, supportive footwear, orthotics, and maintaining a healthy weight. Regular use over several weeks yields the best results.
Users should observe safety guidelines when operating a TENS unit. It should not be used over open wounds, infected tissues, damaged skin, or varicose veins. Individuals with medical devices like pacemakers, or those who are pregnant, have epilepsy, or bleeding disorders, should avoid TENS therapy. Consulting a healthcare professional before starting TENS therapy is recommended, especially if underlying health conditions exist or if pain persists.