There are four kinds of flat bones: the skull (occipital-parietal, frontal-frontal, nasal and vomer), as well as the thoracic (sternum) and ribs and the pelvis (ilium (ischium), and pubis). Flat bones protect internal organs like the brain and heart. Flat bones are somewhat flattened and can be used as a http://symptoms82470.get-blogging.com/11908582/how-does-arthritis-relate-to-bones