Which condition is commonly considered a contraindication to ultrasound therapy?

• A. Advanced arthritis
• B. Cancer
• C. Muscle strain
• D. Back pain

Answer: (D)

Ultrasound therapy delivers energy that heats tissue and increases metabolic activity to aid healing. Because of that heating effect, certain conditions make ultrasound unsafe, with cancer being a clear contraindication. Heating malignant tissue can potentially alter tumor biology, affect tumor spread, or cause damage to nearby structures, so ultrasound is avoided when cancer is present.

Advanced arthritis, muscle strain, and back pain are conditions where ultrasound can still be used or considered depending on the specific clinical scenario and precautions; they are not automatic contraindications like cancer.

So, among the options, cancer is the condition commonly regarded as a contraindication to ultrasound therapy.