The floating ribs are four atypical ribs (two pairs, the XI-XII) located in the lowest part of the human rib cage. They are so called because they are attached only to the vertebrae, and not to the sternum or the cartilage that comes out of the sternum. Some people lack one of the two pairs, while others have a third pair. Most people, however, have two pairs. Ribs
They are the bones that make up the frame of the rib cage. The ribs are elongated bones that are joined at one end, wide, to the so-called thoracic vertebrae and at the other end to the elongated bone called the sternum. In essence, the thorax is made up of only seven of the twelve available pairs in the human body, because only these join the sternum forming a cavity in which the lungs and the heart meet. The rest are called false ribs, because they do not attach directly to the sternum, but stick by a cartilaginous medium to the seventh rib. Gallery
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