1. Thorax
Thoracic Wall

2. Thorax
The thorax is an irregularly shaped cylinder with a narrow opening (superior thoracic aperture) superiorly and a relatively large opening (inferior thoracic aperture) Inferiorly.
The superior thoracic aperture is open, allowing continuity with the neck; the inferior thoracic aperture is closed by the diaphragm.

4. Superior thoracic aperture
Completely surrounded by skeletal elements, the superior thoracic aperture consists of the body of vertebra TI posteriorly, the medial margin of rib I on each side, and the manubrium anteriorly.

5. Inferior thoracic aperture
The inferior thoracic aperture is closed by the diaphragm, and structures passing between the abdomen and thorax pierce or pass posteriorly to the diaphragm.

6. Thorax Thoracic cavity Thoracic wall Surrounded by thoracic wall
Contains heart, lungs, thymus, distal part of trachea, and most of esophagus
Thoracic wall
Consists of skin, fascia, nerves, vessels, muscles, and bones

7. Thoracic wall
The thoracic wall consists of skeletal elements and muscles
Posteriorly, it is made up of twelve thoracic vertebrae and their intervening intervertebral discs
Laterally, the wall is formed by ribs (twelve on each side) and three layers of flat muscles.
Anteriorly, the sternum, which consists of the manubrium of sternum, body of sternum, and xiphoid process.

9. Ribs Two types of classification True ribs (1-7) False ribs (8-10)
Floating ribs (11-12)
Typical ribs (3-9)
Atypical ribs (1,2,10,11,12)

10. R11-12 (Free or floating ribs)
R1-7 (True Ribs)
Vertebrocostal
Attach to sternum via a costal cartilage
R8-10 (False Ribs)
Vertebrochondral
Their cartilages are joined to the cartilage of rib above and via that connection to sternum
R11-12 (Free or floating ribs)
Do not connect even indirectly with sternum but have a costal cartilage on their tips. Tips embedded in muscles

11. Components of ribs Typical Rib (3-9)

12. Atypical Ribs

13. First Rib No Angle Shortest & flattest
Has grooves for subclavian vein and artery

14. 2nd rib
Its main atypical feature is a rough area on its upper surface, the tuberosity for serratus anterior, from which part of that muscle originates.

15. 10th to12th ribs
like the 1st rib, have only one facet on their heads and articulate with a single vertebra.
The 11th and 12th ribs are short and have no neck or tubercle.

16. Thoracic Vertebrae 12 vertebrae Components Body: Spinous process:
Articulates head of rib
Heart shaped
Spinous process:
Inclined downward
Transverse process:
Facet for each rib at costovertebral j.
Pedicle:
Connect transverse process to body
Lamina:
Connect transverse process to spinous process

17. Sternum Midline of anterior chest wall flat bone 3 parts
Manubrium sterni
Opposite T3 &T4
Jugular notch
Body of sternum
Opposite T5-T9
Articulates with 2nd–7th C.C
Xiphosternal joint
Xiphoid process
Flat, cartilagenous process
Unites with body of sternum after middle age
Attached to linea alba caudally

19. Sternal Angle (Angle of Louis)

20. Sternal Angle (Angle of Louis)
Junction between Manubrium and Body of sternum - at this level ---
The second ribs articulate with the sternum.
The aortic arch begins and ends.
The trachea bifurcates into the right and left bronchi at the carina.
A transverse plane can pass through the intervertebral disk between T4 and T5.