IFT Interferential-Therapy

As physiotherapists, we pride ourselves on our “hands-on” approach with our patients. We are respected in the field of health as having excellent manual skills. However, we may also make the most of electrotherapy modalities as an effective adjunct to our hands-on treatment. The most commonly found electrotherapy machines in physiotherapy practices are laser, ultrasound and interferential machines. Laser and ultrasound therapy are explained in detail under their own headings. Here interferential therapy is explained.
Interferential therapy is a type of TENS (Transcutaneous Electrical Nerve Stimulation) which has two alternating currents that are applied to the skin. Interferential machines are set a medium frequency current with controls on the machine to adjust the strength of the current and the type of nerve stimulation required. Either two or four pads are applied around the area that needs to be treated (with either a damp sponge or gel between the pads and the skin). The two alternating currents intersect in between the pads and the result of the interconnecting currents is a new frequency (called a beat frequency) which has the desired effect of either stimulating muscle contraction (when the beat frequency is low) or achieving pain relief (when the beat frequency is higher).

Inferential therapy has several benefits:

• It can help stimulate a weak muscle by causing it to contract repetitively which will help the muscle regain its function, strength, and endurance. This is particularly effective for muscles that have wasted after being immobilized in a cast or following neurologically caused muscle weakness such as with a stroke.
• It is very effective for pain relief. Interferential stimulation of the nerves causes the central nervous system to facilitate the release of endorphins (pain-relieving chemicals) into the body.
• It stimulates vasodilation in the blood vessels which results in the removal of inflammatory toxins and thus eases swelling.