Principle:
Ultrasound therapy works by converting electrical energy into mechanical (sound wave) energy through a piezoelectric crystal  (e.g.Quart) inside the transducer head. When alternating current passes through the crystal, it vibrates rapidly, producing high-frequency sound waves(typically 1 MHz or 3 MHz). These waves travel through the conductive gel into body tissues, where they create microscopic vibrations that lead to therapeutic effects.
Effects:
1. Thermal Effects (Heating):
- Increases tissue temperature and blood flow
- Enhances soft tissue extensibility
- Relieves muscle spasm and pain
- Promotes relaxation
2. Non-Thermal (Mechanical) Effects:
- Causes cavitation and microstreaming in tissues
- Stimulates cellular repair and regeneration
- Reduces inflammation and edema
- Accelerates healing of soft tissue injuries
Common Clinical Uses:
- Muscle and ligament injuries (sprains, strains)
- Tendinitis, bursitis
- Joint stiffness or contracture
- Scar tissue management
- Haematoma
- Chronic pain and post-surgical recovery