What defines a closed injury?

A closed injury is characterized by the absence of a break in the skin, which means that while there may be damage to internal tissues, muscles, or organs, the external surface remains intact. This can include bruises, strains, and fractures that do not pierce the skin.

The correct option highlights this critical aspect of a closed injury, distinguishing it from other types of injuries, such as open wounds or superficial scratches, which either breach the skin or only affect the outer layers without involving deeper tissues. In a closed injury, even if there is internal trauma, there is no visible damage on the skin, which is a defining feature that impacts treatment and assessment protocols. Understanding this distinction is vital for EMTs in evaluating injuries and determining appropriate care.