Therapeutic Ultrasound is a deep heating modality that emits high-frequency acoustic vibration that is above the human audible spectrum. Therapeutic ultrasound reaches underlying tissues as deep as 1 to 5 centimeters.

When electrical energy is applied to a crystal, it causes it to vibrate at a high frequency and to produce ultrasound. Ultrasound is delivered by continuous or pulsed wave and provides a high heating intensity. Therapeutic ultrasound stimulates the repair of damaged tissues, relieves pain, increases blood flow, relaxes muscle spasms, and may speed the healing process.