The thoracic cage, commonly called the rib cage, provides protection for the 2 lungs, heart, esophagus, diaphragm and liver. It also supports the shoulders and upper limbs.
The sternum (breast bone) is made of 3 fused bones called the manubrium, body and the xiphoid process at the very tip. The xiphoid process starts as cartilage and becomes bone. The body of the sternum is where you want to press down during CPR but not the xiphoid process as that can break off. Between the manubrium and body is a tiny sternal-angle-fibrocartilage joint.
The word costal pertains to the ribs. The top 7 ribs are called true ribs because a separate piece of cartilage attaches the ribs to the sternum as opposed to the false ribs whose costal cartilage joins together to create what is called the costal margin which connects to the bottom of the sternum all together. You could feel this on your body. The bottom 2 ribs are called floating ribs because they are not attached by cartilage. The space between the ribs is called the intercostal space. The place where the two costal-margins meet is called the infrasternal angle. Pregnancy causes this angle to increase from 68° to 103°.
Fontanelles
The part where the bones come together are called fontanelles. The soft parts of a baby’s head are these fontanelle spaces. The anterior fontanelle takes two years to close because the brain is growing and the posterior fontanelle closes in 2 months.
And finally, we have 2 sets of teeth because chewing is important.
Sacrum: Forms the back wall of pelvis. The foramina are what the nerves run through the sacral canal. The apex is the tip of the sacrum. The sacral hiatus is the hole on very bottom. The auricular surface articulates with the hip bones and is shaped like an ear. The median sacral crest is where the spinous processes would be. The ridges sticking out on the anterior side of the sacrum are a result of fusion.
The coccyx is the tail bone.
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