Which of the following is a contraindication for ultrasound?

• A. Acute ankle sprain
• B. Mild skin irritation
• C. Neoplasm
• D. Reversible joint stiffness

Answer: (C)

Ultrasound delivers energy that can heat tissue and also create non-thermal effects that stimulate tissue activity. Heating or stimulating cells in a tumor area can potentially influence tumor behavior, so applying ultrasound over a neoplasm is avoided. This makes neoplasm an absolute contraindication for ultrasound therapy.

Other options don’t pose the same strict restriction. An acute ankle sprain isn’t inherently a contraindication; ultrasound can be used cautiously in acute injuries to manage inflammation and promote healing. Mild skin irritation isn’t a reason to avoid ultrasound entirely; the clinician would adjust intensity or use protective measures. Reversible joint stiffness can often benefit from ultrasound to improve tissue extensibility and ROM, so it’s not contraindicated.