Overview of the Thorax Flashcards
What forms the thoracic cage?
12 pairs of ribs
Sternum
Costal cartilages
12 thoracic vertebrae
What are the costocartilages attached to?
The sternum and the ribs
What are the components of the sternum?
Jugular notch (on the manubrium)
Clavicular notch (on the manubrium)
Manibrium
Sternal angle (between the manibrium and the body)
Body
Xiphisternal junction (between xiphisternal and the body)
Xiphoid Process
What are the special features of the thoracic vertebrae?
- Long inferiorly angled spinous processes
- Costal facets (except the last 2 or 3 thoracic vertebrae) which exist on the transverse process.
- Two demifacets located laterally on the bodies of vertebrae T2-T9
Which thoracic vertebrae bodies contain demifacets?
How many are there? How do they articulate with the ribs.
T2-T9.
There is a superior demifacit and an inferior demifacet.
The superior facet articulates with the head of the corresponding rib (i.e same rib number), while the inferior facet articulates with the head of the rib below it (higher number)
How does the head of the rib articulate with the thoracic vertebrae? What are the parts of the head of the rib?
There is an:
- Inferior articular facet
- Superior articular facet
The inferior facet corresponds with the vertebrae of its same number, while the superior facet corresponds with the vertebral body above it.
Therefore, if we are dealing rib 7 the inferior aspect of the rib will articulate with vertebral body 7 while the superior aspect will articulate with the vertebral body above it (lower number) 6
Which ribs are considered typical ribs?
T3-T9
Which ribs are considered True ribs?
First rib through the 7th rib
Which ribs are considered false ribs? What does it mean to be a false rib?
Ribs eight through ten. It means they don’t have their own insertion on to a costocartilage. Instead they share a costacartilage.
Which ribs are considered atypical ribs?
1, 2, 10, 11, and 12
What are the components of the first rib? (atypical)
- Scalene tubercle
2. Single facet for articulation only with T1 vertebrae
What are the components of the second rib? (atypical)
Tubercle for origin of serratus anterior muslce
What are the components of the tenth rib? (atypical)
Only one facet for articulation with only one vertebrae
What are the components of the 11th and 12th rib? (atypical)
They have no necks or tubercles
They are free floating
They articulate with only one vertebrae
What Thoracic bodies are at the same level as the manibrium?
T3 and T4
Where can the jugular notch be palpated?
Palpated at the T2 vertebral level
Where can the sternal Angle (of Louis) be palpated?
Palpated at the vertebral T4 level
Where is the Xiphoid process located?
Located at the level of T10
What is the most anterior part of the bony part of the chest?
Sternal angle (manubriosternal joint)
How does communication occur between the thoracic cavity and the abdomen and neck?
Through the Superior and Inferior Thoracic aperture.
What are the structures passing through the superior thoracic aperture?
Trachea
Esophagus
Nerves
Blood Vessels that either supply or drain the head and neck.
What are the structures passing through the inferior thoracic aperture?
Inferior Vena Caval Hiatus (T8) Esophageal Hiatus (T10) Aortic Hiatus (T12)
What are the various intercostal muscles? (4)
- External Intercostal
- Internal Intercostal
- Innermost Intercostal
- Transversus Thoracic