Thorax Self Study

Question 1

True ribs

Answer 1

Ribs 1-7

– A true rib is defined by its “direct” attachment to the sternum via its own costal cartilage

Question 2

False ribs

Answer 2

Ribs 8, 9, and 10
– A false rib is defined by the “indirect” attachment to the sternum via a connection of its costal cartilage to the costal cartilage of the rib above

Question 3

Floating ribs:

Answer 3

Ribs 11 and 12
– A floating rib has rudimentary cartilage that makes no connection to the sternum but rather ends in muscle of the posterior abdominal wall

Question 4

Typical Ribs

Answer 4

Ribs 3-9
– A typical rib is defined by having two facets on its head for articulation with its corresponding numeric vertebrae as well as the vertebrae above.

In addition, it has a neck, a tubercle articulation with the transverse process of the corresponding vertebrae, and a thin flat curved body which bends at the costal angle and has a costal groove.

Question 5

Atypical Ribs

Answer 5

Ribs 1,2 and 10-12
– 1st has an atypical shape and only
a single fact on its head
– 2nd has a tuberosity on its body
– 10-12 have only a single facet on their head
– 11-12 are short, have no neck and no tubercle

Question 6

Superior Mediastinum Structures

Answer 6

Thymus
Trachea
Esophagus
Phrenic Nerves 
Vagus nerves 
Azygos vein 
Brachiocephalic veins 
Superior vena cava 
Thoracic duct
Aortic arch 
Brachiocephalic artery
Left common carotid artery 
Left subclavian artery

Question 7

Anterior Mediastinum

Answer 7

Thymus/Fat

Pericardial Ligaments

Question 8

Posterior Mediastinum

Answer 8

Descending Aorta
Vagus nerves
Splanchnic nerves
Thoracic duct 
Esophagus Azygos vein

Question 9

Middle Mediastinum

Answer 9

Pericardium and Heart Ascending Aorta 
Pulmonary Arteries Pulmonary Veins 
Superior vena cava 
Inferior vena cava 
Phrenic nerves

Question 10

Structures shared by superior and posterior mediastinum:

Answer 10

Vagus nerves
Thoracic Duct
Esophagus
Azygos vein

Question 11

Structure shared by superior and anterior mediastinum:

Answer 11

Thymus

Question 12

Structures shared by superior and middle mediastinum:

Answer 12

Phrenic Nerves

Superior Vena Cava

Question 13

What are components of a spinal nerve?

Answer 13

GSA, GSE, GVA, GVE

Question 14

What are components of a ventral ramus?

Answer 14

GSA, GSE, GVA, GVE

Question 15

What are components of a dorsal ramus?

Answer 15

GSA, GSE, GVA, GVE

Question 16

What are components of white rami communicans?

Answer 16

Preganglionic GVE fibers (Sympathetic)

Question 17

What are components of gray rami communicans?

Answer 17

Postganglionic GVE fibers (Sympathetic)

Question 18

What are components of sphlanchnic nerves?

Answer 18

Preganglionic GVE fibers(Sympathetic)

Question 19

What are components of vagus nerves?

Answer 19

Preganglionic GVE fibers (Parasympathetic)

Question 20

Where else are GVA fibers?

Answer 20

Running in the vagus nerve to the brainstem and in the sympathetic chain back to the spinal cord.

Question 21

What are components of cutaneous nerves?

Answer 21

GSA, GVA, GVE

Question 22

What contributes to Cardiac, Pulmonary, Esophageal Plexuses?

Answer 22

Sympathetic and Parasympathetic (vagus nerve)

Question 23

Dorsal Root Ganglia contain what kind of cell the bodies and processes of

Answer 23

GSA and GVA fibers

Question 24

What is the paravertebral ganglia?

Answer 24

Site of synapse between pre and postganglionic sympathetic

GVE neurons

Question 25

What is the paravertebral ganglia associated with and what is the site of synapse?

Answer 25

splanchnic nerves and are the site of synapse between pre and postganglionic sympathetic GVE neurons

Question 26

Terminal Ganglia site of synapse is

Answer 26

between pre and postganglionic parasympathetic GVE neurons, and are found in or near the walls of organs

Question 27

The sternal angle serves as a land mark for what structures?

Answer 27

The sternal angle marks the approximate level of
the 2nd pair of costal cartilages, which attach to
the second ribs, and the level of the intervertebral
disc between T4 and T5. The angle also marks a
number of other features:
-Boundary between the superior and inferior
portion of the mediastinum
-Passage of the thoracic duct from right to left
behind esophagus
-Tracheal Bifurcation
-End of the azygos system into SVC
-Ligamentum
arteriosum
-Loop of left recurrent laryngeal
nerve around aortic arch
-Aortic arch starts and ends

Question 28

What is the blood supply of the pericardium layers?

Answer 28

pericardiacophrenic vessels

branches of the internal thoracic vessels and the thoracic aorta

Question 29

What is the innervation of the pericardium layers?

Answer 29

GVE and GVA fibers from the vagus nerves and the sympathetic chain.

Question 30

What is the innervation of the fibrous and parietal layer of serous pericardium?

Answer 30

GSA fibers through the phrenic nerves. (Again, these

structures receive somatic sensation while the visceral pericardium does not) .

Question 31

Arteries originating from the ascending aorta

Answer 31

Right and Left Coronary arteries

Question 32

Branches of the Right Coronary Artery

Answer 32

• SA nodal branch
• Marginal Artery
• Posterior Interventricular Artery (Posterior descending)

Question 33

Branches of the Rt Coronary artery supply?

Answer 33

• right atrium,
• right ventricle (the majority of it),
• part of the left ventricle,
• SA node and the AV node,
• part of the interventricular septum (posteriorly)

Question 34

Branches of the Lt Coronary Artery

Answer 34

• Left Anterior Descending (Anterior Interventricular Artery)
• Circumflex

Question 35

Branches of the Lt Coronary artery supply?

Answer 35

-left atrium,
-left ventricle (the
majority of it),
-part of the right ventricle,
-the interventricular septum

Question 36

Describe the pericardium layers?

Answer 36

fibrous outer layer and two serous layers: parietal and visceral

Question 37

Where are the intercostal vein artery and nerve found?

Answer 37

At the inferior border of the superior rib.