Ultrasound is an adjunctive treatment that utilizes high or low-frequency sound waves to elicit a therapeutic effect. These sound waves penetrate into the muscles to cause deep tissue/muscle warming. This promotes tissue relaxation and is useful in treating muscle spasms and tissue injury. The sound waves also cause blood vessels to dilate, increasing blood flow into the desired region, resulting in an increased rate of tissue healing. The frequency of the sound waves can also be altered to facilitate a decrease in inflammation.