Transcutaneous Electrical Nerve Stimulation (TENS) offers a non-invasive approach to managing various types of pain, including discomfort stemming from musculoskeletal conditions. This article focuses on the specific application of TENS therapy for Achilles tendonitis, a common condition affecting the large tendon at the back of the ankle.
How TENS Therapy Works
A TENS unit delivers low-voltage electrical impulses through electrodes placed on the skin. These impulses primarily alleviate pain through the “Gate Control Theory,” which proposes that stimulating sensory nerves can “close the gate” in the spinal cord, preventing pain signals from reaching the brain. The impulses travel faster than pain signals, reducing discomfort. TENS therapy also encourages the release of endorphins, the body’s natural pain-relieving chemicals, which further diminish pain sensation.
Precise Pad Placement for Achilles Tendonitis
The Achilles tendon connects the calf muscles (gastrocnemius and soleus) to the heel bone (calcaneus). Proper pad placement is important for effective TENS application. One common strategy involves direct placement, where one electrode pad is positioned above the painful area on the calf muscle and another below, near the heel insertion. This allows the electrical current to stimulate across the affected region.
Alternatively, if the tendon itself is too sensitive, pads can be placed around the painful area. Another effective method is placing pads directly on the calf muscle belly, specifically the gastrocnemius and soleus, to help relax muscle tension. Ensure the skin is clean and dry before applying pads. Always use at least two pads to create a complete electrical circuit, and avoid placing them over bony prominences or irritated skin.
Optimal TENS Settings and Usage Guidelines
Selecting appropriate TENS settings is important for maximizing pain relief. Frequency (Hz) dictates the number of electrical pulses per second. For acute pain, 80-120 Hz is recommended for immediate relief. For chronic pain, 2-10 Hz are used, promoting longer-lasting relief through endorphin release.
Pulse width (µs) refers to the duration of each electrical impulse, typically 50-250 µs. Adjust intensity to a “strong but comfortable” tingling sensation, avoiding uncomfortable muscle contractions. Begin with lower settings and gradually increase. A typical TENS session lasts 20-30 minutes and can be repeated multiple times a day, with a few hours between sessions.
Safety Considerations and When to Seek Medical Advice
TENS therapy is generally safe, but certain precautions are necessary. Do not use it over broken or irritated skin, the front of the neck (carotid sinus), or directly over the eyes or mouth. Individuals with implanted electronic devices, such as pacemakers or defibrillators, should avoid TENS therapy entirely. Consult a doctor regarding its safety during pregnancy.
TENS manages pain symptoms; it is not a cure for Achilles tendonitis. If you experience severe pain, noticeable swelling, warmth, redness, or difficulty walking, consult a healthcare professional promptly. These symptoms could indicate a serious injury requiring immediate medical attention.