Compléter Thoracic cageVersion en ligne Identify the bones that form the thoracic cage. Boxes that require multiple answers are in alphabetical order. par Kristani Cochran 1 true costal 7th sternum xiphoid 11 process cage 7 8 manubrium thoracic 12 inferior superior 1 body floating false ribs 10 middle cartilage The is composed of quite a few parts . First is the , which is an elongated flat bone forming the middle part of the anterior thoracic wall . It is composed of three parts , the ( which is the portion ) , ( the portion ) , and ( the portion ) . The are also a part of this cage , - attach anteriorly to the sternum through strips of and are known as ribs . - are ribs that only attach to the cartilage . - do not attach to anything are known as ribs .