Thoracic skeleton

The thoracic skeleton consistes of 12 thoracic vertebrae, 12 pairs of ribs and one sternum. Get the whole picture with the commissural skeleton. Note that there is very little rib cartilage left in the exposed dry bones.

thorax.JPEG

1. Thoracic cage
・Superior thoracic aperture (1-1), Inferior thoracic aperture (1-2)
・Costal arch (margin) (2)
・Infrasternal angle (3); has an angle of 70-80 degrees in adults.
・Thoracic index = (sagittal diameter / transverse diameter) × 100
How humans differ from other animals
2. Sternum
= Manubrium of sternum + Body of sternnum + Xiphoid process
・Manubrium of sternum (4)
・Clavicular notch (5) --- Sternoclavicular joint (6)
・Body of sternum (7)
・Sternal angle (8);Palpate it with your own body.
The anatomical or clinical significance is
・Xiphoid process
Ossification time is extremely late (in middle age)
3. Rib
Compare the curvature and torsion of each rib
・What are the characteristics of the upper and lower ribs
・How can left and right ribs be determined
・Rib = Rib + Costal cartilage
・Head (of rib) (9) ---- Joint of head of rib
・Tubercle (of rib) (10);Do costa XI, XII have it ---- Costotransverse joint
Together, the above two joints are called the Costovertebral joints.
Think of the motion model of the costovertebral joint in terms of a "bucket handle" movement.
What would the movement of the entire thorax look like
・Angle (of rib) (11)
・Costal groove (12);What runs?
Is it on every rib
・Groove for subclavian artery (13-1)・Groove for subclavian vein (13-2)(of the first rib)
・Scalene tubercle(14)

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