Transcutaneous electrical nerve stimulation (TENS) is the use of an electrical current produced by a battery-operated device to stimulate the nerves for therapeutic purposes. The unit is usually connected to the skin using two or more electrodes on trigger or acupuncture points. The electrical current can help reduce pain and stimulate nerve tissue.

Interferential Current (IFC) is another form of electrical stimulation. It uses two alternating medium-frequency electrical currents whereas the TENS uses one alternating current at a low frequency. The IFC and TENS machines are very similar and either can be used to reduce pain. 

Physiotherapy uses TENS and IFC as part of a treatment session. Electrical currents can be effective at relieving pain immediately and can last up to 2-4 hours. Therapists add exercises, re-train movement and mobilize joints with TENS and IFC for the patient’s symptom and functional improvement.