Which is a non-thermal indication for ultrasound?

• A. Facilitate tissue healing
• B. Open wounds
• C. Fractures
• D. Acute nerve injury

Answer: (A)

Non-thermal ultrasound works by mechanical energy delivered in pulsed mode to stimulate biological processes involved in repair without raising tissue temperature. The energy causes micro-streaming and stable cavitation at the cellular level, which enhances cell membrane permeability and triggers healing pathways. This is why the best indication is to facilitate tissue healing—promoting repair in soft tissues, wounds, and postoperative healing without relying on warming the tissue.

Other conditions listed are not the primary non-thermal indications in general practice. Fracture healing and acute nerve injuries have more specific or limited indications, and open wounds, while related to healing, are not the general non-thermal concept itself.