THORAX IV

Question 1

What are the anterior, posterior, superior and inferior borders of the posterior mediastinum?

Answer 1

Anterior- pericardial sac
Posterior- bodies of T5-T12 vertebrae
Superior- transverse thoracic plane
Inferior- thoracic surface of the diaphragm

Question 2

Where does the descending aorta begin and end?

Answer 2

T4-T12

Question 3

What are the 7 groups of branches off the thoracic aorta?

Answer 3

The bronchial arteries, the mediastinal arteries, the oesophageal arteries, the pericardial arteries, the superior phrenic arteries and the intercostal and subcostal arteries

Question 4

What do vessels in the azygous system run between?

Answer 4

The pleura and the the vertebral column

Question 5

What does the azygous system of veins drain?

Answer 5

The posterior thoracic wall

Question 6

What does the azygous system of veins provide collateral circulation to?

Answer 6

The venae cavae

Question 7

How many posterior intercostal veins are there?

Answer 7

11

Question 8

Where does the 1st posterior intercostal vein drain into?

Answer 8

Into the brachiocephalic vein or the vertebral vein

Question 9

Where do the 2nd and 3rd (and often 4th) posterior intercostal veins drain?

Answer 9

Into the superior intercostal vein

Question 10

Where do posterior intercostal veins 5-11 drain?

Answer 10

Into the azygous vein on the right, or the hemiazygous and accessory hemiazygous veins on the left

Question 11

What’s the thoracic duct inferior to?

Answer 11

The coeliac trunk

Question 12

Where do the left and right vagus nerves run in relation to the oesophagus in the thorax?

Answer 12

The left vagus runs anterior and the right vagus runs posterior to the oesophagus

Question 13

Where do the thoracic splanchnic nerves arise?

Answer 13

The sympathetic trunk

Question 14

What do the thoracic splanchnic nerves supply?

Answer 14

They run inferiorly to supply the abdomen

Question 15

What spinal nerve roots does the greater splanchnic nerve originate from?

Answer 15

T5-T9 or T10

Question 16

What spinal nerve root(s) does the lesser splanchnic nerve originate from?

Answer 16

T10-T11

Question 17

What spinal nerve root(s) does the least splanchnic nerve originate from?

Answer 17

T12

Question 18

What is in the posterior mediastinum?

Answer 18

The mediastinal parts of the lungs

Question 19

What is an annulus of the heart?

Answer 19

The base of a heart valve that supports the valve’s cusps

Question 20

What’s the moderator band in the right ventricle and what’s its purpose?

Answer 20

A muscular band of heart tissue which carries part of the bundle branch of the AV bundle of the conductive system of the heart to the anterior papillary muscle, which facilitates conduction time

Question 21

What runs in the anterior atrioventricular groove of the heart?

Answer 21

The right coronary artery

Question 22

What runs in the interventricular groove of the heart?

Answer 22

The anterior inter ventricular artery

Question 23

What’s the function of the ductus arteriosus in a foetus?

Answer 23

The ductus arteriosus connects the pulmonary artery to the aortic arch, allowing most of the blood from the right ventricle to bypass the foetal lungs

Question 24

Along what side of T5-T7 does the descending thoracic aorta pass?

Answer 24

Along the left side

Question 25

What nerve supplies the muscle of the diaphragm?

Answer 25

The phrenic nerve

Question 26

What does the diaphragm initially develop as and at what vertebral level?

Answer 26

The diaphragm begins as a central tendon at C2

Question 27

What causes the diaphragm to descend?

Answer 27

Differential growth

Question 28

What is hemidiaphragm?

Answer 28

Paralysis of half of the diaphragm due to its motor supply from the phrenic nerve becoming injured

Question 29

What is the median arcuate ligament?

Answer 29

A ligament under the diaphragm that links the right and left crura of the diaphragm

Question 30

What is the medial arcuate ligament?

Answer 30

A tendinous fascia that arches over the psoas major muscle as it passes through the diaphragm

Question 31

What is the lateral arcuate ligament?

Answer 31

A ligament under the diaphragm that arches across the upper part of the quadratus lumborum muscle. It's traversed by the subcostal nerve, artery and vein

Question 32

What do the ganglia associated with levels T1-T5 supply?

Answer 32

Cardiac branches to the heart

Question 33

What do rami communicates do?

Answer 33

Connect the trunks to the spinal nerves (intercostal nerves), providing sympathetic thoracic supply to parietal structures

Question 34

What bounds the anterior triangle of the neck?

Answer 34

The midline of the neck, the anterior border of the SCM and and the inferior border of the mandible

Question 35

What bounds the posterior triangle of the neck?

Answer 35

The middle 2/3 of the the clavicle, the anterior border of the trapezius muscle and the posterior border of the SCM

Question 36

Where does the SCM originate and insert?

Answer 36

Originates on the anterior surface of the manubrium and the superior border of the anterior surface of the medial 1/3 of the clavicle. It inserts on the lateral surface of the mastoid process and the nuchal line of the occipital bone

Question 37

What's the nerve supply to the SCM?

Answer 37

The accessory nerve on the same side supplies motor innervation, while the cervical plexus supplies sensation from the ventral primary rami of C2 and C3

Question 38

What's the action of the SCM?

Answer 38

Contralateral cervical rotation, ipsilateral cervical flexion

Question 39

What is torticollis?

Answer 39

Also known as wry-neck, this is a dystonic condition defined by an abnormal, asymmetrical head or neck position

Question 40

Where does trapezius originate and insert?

Answer 40

It originates on the occipital bone, the ligamentum nuchae, and the spinous processes of T1-T12. It inserts on the lateral 1/3 of the clavicle, the acromion and the scapular spine

Question 41

What is the nerve supply to the trapezius muscle?

Answer 41

The accessory nerve provides motor innervation, while the ventral primary rami of spinal nerves C3 and C4 provide sensory innervation (cervical plexus)

Question 42

What is the action of the trapezius?

Answer 42

The upper descending fibres are responsible for elevation of the scapulae. The lower, ascending fibres are responsible for depression of the scapulae. The middle fibres retract the scapulae.

Question 43

What are the contents of the posterior triangle of the neck?

Answer 43

The accessory nerve, branches of the cervical plexus, roots and trunks of the brachial plexus, the phrenic nerve, the subclavian artery, the transverse cervical artery, the supra scapular artery, the external jugular vein, occipital and supraclavicular lymph nodes, the inferior belly of the omohyoid, the anterior, middle and posterior scalene, levator scapulae and splenius