Ultrasound therapy is used to treat injuries to the tissues beneath the surface of the skin by producing mechanical vibrations. Heat is thought to be produced by pressing and continuously moving the metal head of the ultrasound machine over the skin in the region of the injury or the area affected by a chronic medical condition. The benefits of ultrasound are disputed with little scientific research to back the claims of successful treatments by individual therapists.
Mechanical vibration creates sound that can be heard by human beings in a certain range, with vibrations above this level known as ultrasound. Ultrasonic waves are passed through the metal head of the ultrasound machine to pass the produced waves through the surface of the skin to the tissues beneath. To complete a successful ultrasound therapy, a gel is placed on the skin of the patient in the region of the injury to stop ultrasonic waves from dispersing when they come into contact with the air. Therapies usually last between three and five minutes repeated daily for quick recovery from a soft tissue injury and less frequently for long-term medical conditions.
Frequency can be altered during an ultrasound therapy to ensure that the mechanical vibrations reach the desired tissues thought to be damaged. Higher ultrasonic frequencies are mostly used to treat damaged tissues close to the surface of the skin. Lower frequencies are used to pass ultrasonic waves deeply into the tissues of the body.
No specific theory has been proven as to why an ultrasound therapy would promote healing and ease pain and stiffness in an affected area. One theory suggests the production of vibrations in the tissues beneath the skin heats the tissues within the damaged area beneath the skin to promote healing and to increase the flow of blood passing through the tissues. By increasing the production of collagen within the damaged and surrounding tissues, healing times are reduced and the amount of scar tissue surrounding the injury is limited. The use of ultrasound is also thought to reduce the chances of muscle spasm causing pain in the area surrounding damaged tissues.
Dangers are also associated with ultrasound therapy including both long-term and short-term problems. In the short term, the increased blood flow stimulated by ultrasonic waves can reduce the speed of recovery when applied soon after an injury has taken place. As the blood flow is increased in tissues, tumors and cancerous tissues that are already present in the body can be spread with the use of ultrasound therapy.