What type of injury involves an open wound with a flap of skin?

An avulsion is a specific type of injury that involves an open wound in which a portion of skin is forcibly detached or removed, leaving a flap of skin. This type of injury can occur due to trauma, such as a fall or an accident where the skin is pulled away from the underlying tissue. The flap of skin may still be partially attached, which distinguishes it from other types of open wounds.

In contrast, an incision refers to a clean cut made by a sharp object, such as a knife or scalpel, and typically does not involve a flap of skin. A contusion is a bruise that occurs when blood vessels are damaged, resulting in discoloration, but does not involve an open wound at all. Excoriation refers to skin that has been scraped or rubbed off, which also does not involve a flap of skin. Thus, avulsion is the correct answer as it directly describes the situation where there is both an open wound and a flap of skin.