What type of fracture is characterized by a closed break with no wound?

A simple fracture is characterized by a closed break in the bone that does not involve any wounds penetrating through the skin. This type of fracture typically occurs when there is a direct impact or stress on the bone, leading to a clean break without exposing the bone to the outside environment. The key aspect of a simple fracture is that both ends of the broken bone still remain within the body, meaning there is no communication with the external environment which is critical in differentiating this type from others.

On the other hand, compound and open fractures involve a break that extends through the skin, exposing the bone to the outside, which increases the risk of infection and complications. A complex fracture usually refers to a more complicated break involving multiple fragments or additional injuries surrounding the fracture site. Therefore, the defining feature of a simple fracture is its closed nature, which is why it is the correct answer.