Thoracic Cage EDU - Module 2 > Thorax & Spine > Thorax & Spine

Home , Sternal angle, Suprasternal notch, Thoracic vertebrae, Xiphoid process

Thoracic cage

• Protects the chest organs (the heart and lungs).

Main Structures: The sternum (aka, breastbone) lies anteriorly. 12 thoracic vertebrae lie posteriorly. 12 ribs articulate with the thoracic vertebrae. Sternum

• Manubrium (superiorly)

• Body (long and flat, middle portion)

• Xiphoid process

- Easily injured during chest compression (for CPR).

• Sternal angle

- Where manubrium and body meet

- Easily palpated to find rib 2

• Sternal indentations:

- Jugular notch (aka, suprasternal notch) is on the superior border of the manubrium.

- Clavicular notches are to the sides of the jugular notch; these are where the clavicles (aka, collarbones), articulate with the sternum.

- Costal notches articulate with the costal cartilages of the ribs ("costal" refers to the ribs).

Rib Types

• True ribs

- Ribs 1-7; articulate with the sternum directly via their costal cartilages.

• False ribs

- Ribs 8-12; do not articulate directly with the sternum.

- Ribs 11 and 12 are "floating ribs," do not articulate at all with the sternum.

1 / 2 Rib Features

• Head

- Articulates with the vertebral body; typically comprises two articular surfaces separated by a bony crest.

• Neck

- Extends from the head, and terminates at the tubercle.

• Tubercle

- Comprises an articular facet, which is where the rib articulates with the transverse process of the vertebra.

• Shaft

- Longest portion of the rib, extends from tubercle to rib end.

• Angle

- Bend in rib, just lateral to tubercle.

Rib/vertebra articulation

• Head and tubercle of rib articulate with body and thoracic process of vertebrae.

Intercostal spaces

• The spaces between the ribs

• House muscles and neurovascular structures.

- Intercostal neurovascular bundle, especially the intercostal artery, must be avoided during insertion of a chest tube.