What is the primary characteristic of grattage?

Grattage refers specifically to the method of rubbing or scraping off morbid growths or lesions from the skin or other tissues. This technique can be used in various medical contexts to help remove abnormal tissue, allowing for further examination or treatment of the underlying condition. The process is particularly important in dermatology and can be utilized to promote healing or prevent infection by removing unhealthy or diseased tissue. This precision in targeting and removing unwanted growths highlights the significance of grattage in medical practices focused on skin health.

The other options describe unrelated medical procedures: injection of medication pertains to administering drugs directly into the body, which does not involve scraping; removing blood clots is typically done through various medical interventions like thrombectomy or medication, rather than grattage; and physical therapy techniques focus on rehabilitation and movement rather than the removal of tissue.