Broken Bones (Fractures) happen to people of all ages. Most often they occur as a result of an automobile accident, fall or sports injury. When a fracture occurs, it is often an emergency situation. This is especially true if the fracture occurs in a larger bone, like the humerus (upper arm bone), femur (thigh bone) or tibia and fibula (lower leg bones) or if the broken bone breaks through the skin. There are two primary types of fractures: open and closed. An open fracture is when the broken bone goes through the skin, and is often accompanied by bleeding. A closed fracture, which is the more common type of fracture, is a broken bone that does not penetrate the skin.