The thoracic cage, also known as the rib cage, consists of 24 ribs and a sternum, which totals to 25 bones. The 24 ribs are paired, with 12 on each side of the body. These ribs are divided into three categories: true ribs, false ribs, and floating ribs.
True ribs (ribs 1-7) attach directly to the sternum via costal cartilages. False ribs (ribs 8-12) do not attach directly to the sternum; ribs 8-10 connect indirectly through the costal cartilage of the 7th rib, while ribs 11 and 12, known as floating ribs, have no anterior attachment at all.
The sternum, located at the front of the thoracic cage, is made up of three parts: the manubrium, body, and xiphoid process. Together, these bones provide structure and protection to vital organs within the thoracic cavity, including the heart and lungs, while also providing attachment points for muscles involved in respiration and upper limb movement.