Ultrasound therapy uses sound waves for treatment commonly for those with musculoskeletal issues. This includes symptoms and disorders of tendinitis, bursitis, gout, osteoarthritis, rheumatoid arthritis, low back pain and fibromyalgia. Pain commonly occurs with muscles, bones and joints. Instead of electricity, the ultrasound unit stimulates tissue with sound waves. This type of therapy has been proven and has been in use since the 1950s. Ultrasound devices can be used in the areas of the neck, shoulders, wrists, upper and lower back, hips, legs, knees and feet.