Transcutaneous electrical nerve stimulation (TENS), interferential current and ultrasound therapies are the most-used electrotherapy methods among patients with chronic back pain. These patients enjoy significantly greater improvement in disability, pain and quality of life.
Interferential current is essentially a deeper form of TENS. The high-frequency carrier waveform penetrates the skin more deeply, with less user discomfort for a given level of stimulation. Deep in the tissues, the carrier waveform is cancelled out, resulting in a TENS-like signal deep under the skin, stimulating the nerves for therapeutic purposes and pain relief.