Anatomy: Practical 2 - Thorax and the Lungs

Question 1

in the thoracic cage, where are:

1) superior thoracic aperture?
2) inferior thoracic aperture

Answer 1

The superior thoracic aperture, also known as the thoracic inlet or outlet, connects the root of the neck with the thorax.

The inferior thoracic aperture connects the thorax with the abdomen.

Question 2

Answer 2

Question 3

how does the chest move in an anterior-posterior axis during inspiration and expiration?

how does the chest move in an lateral / outwards axis during inspiration and expiration?

Answer 3

anterior-posterior axis

• *Inspiration:** Forwards/outwards
• *expiration:** backwards/inwards

lateral / outwards axis:

• *Inspiration:** laterally / outwards
• *​expiration:** medially /inwards

during inspiration: increases the anterior-posterior diameter of the chest, increasing intrathoracic volume & the lateral diameter of the chest, increasing intrathoracic volume.

Question 4

where does the right and left dome of the diaphragm reach to on the ribs?

Answer 4

right dome: upper border of 5th rib

left dome: lower border of 5th rib

Question 5

where can the IC veins drain? (anteriorly & posteriorly?

Answer 5

anteriorly: internal thoracic vein (which then goes into brachiocephalic()
posteriorly: azygously

Question 6

intercostal spaces are named after the rib from above or below?

Answer 6

above :)

Question 7

how many pairs of floating and true ribs do u have?

Answer 7

floating: 2 (11,12)
false 3 (8,9,10)

Question 8

The surface relations of the inferior margin of the parietal pleura can be pinpointed on the surface at which three different areas around the thorax?

Answer 8

the midaxillary line, the midclavicular line and the vertebral column.

Question 9

label these correctly x

Answer 9

Question 11

what is the green?

Answer 11

costodiaphragmatic recess :)

Question 12

how many true ribs do you have?

Answer 12

7 (1 to 7)

Question 13

what is the path of the inferior margin of the parietal pleura? (include vertebra levels)

Answer 13

The inferior margin of the parietal pleura takes an oblique path laterally from the l_evel of rib 8_ in the midclavicular line to rib 10 in the midaxillary line and the T12 vertebra at the vertebral column.

Question 14

at what spinal level do the following pass through the diaphragm?

IVC?

Oesphagus?

Aorta?

Answer 14

IVC: T8

Oesophagus: T10

Aorta: T12

mneuomic: I 8 (IVC - T8) 10 eggs (T10 esophagus), at 12 (aorta t12)

Question 16

which are the primary and accessory muscles of respiration?

Answer 16

primary: diaphragm
accessory: intercostal muscles

Question 17

which of the following are involved in inspiration or expiration:

ectus abdominis:

pectoralis minor:

scalenes:

external oblique:

sternocleidomastoid:

Answer 17

rectus abdominis: expiration

pectoralis minor: inspiration

scalenes: inspiration

external oblique: expiration

sternocleidomastoid: inspiration

Question 18

why are the recesses clinically important?

Answer 18

they provide a location where fluid can collect

Question 19

the costal cartilage of which rib articulates with the sternal angle?

Answer 19

2nd

Question 20

what is the order (from out to in) of intercostal muscles?

Answer 20

external -> internal -> innermost

Question 22

what are the recesses?

what are the two recesses and where located?

Answer 22

In some areas of the thorax, the lungs do not completely occupy the pleural cavity. This is especially true for the inferior region of the pleural cavity, where the inferior margin of the parietal pleura extends approximately two ribs inferior to the lung

1. costadiaphragmatic: located between the costal pleurae and diaphragmatic pleura
2. costomedialstinal: located betweeen the costal pleurae and the mediastinal pleurae, behind the sternum

Question 23

what are the three parts that the diaphragm attaches to the thorax by?

Answer 23

1) sternal part
2) costal part

3) lumbar part

Question 24

how does respiration occur?

Answer 24

• predominantly achieved by the action of the diaphragm, which contracts during inspiration, pushing the abdominal contents downwards.

By increasing the volume of the thoracic cavity, the pressure within reduces (although by a tiny amount!) and a pressure gradient drives the flow of air to fill the increased thoracic volume at the same pressure of the surrounding atmosphere.

• in expiration, the volume of the thoracic cavity is reduced, creating a pressure gradient that forces air out.

Question 25

which vein is this? which side of thorax?

Answer 25

zygous vein - right side !

Question 26

Answer 26

Question 27

If passing a needle through the thoracic cage to sample air or fluid in the pleural cavity (pleural tap/aspiration), should you pass the needle immediately above or below the rib?

Answer 27

The primary and larger intercostal neurovascular bundles run immediately below each rib. To avoid damaging these (and causing bleeding / neuropathy) during a pleural tap or aspiration, **insert the needle just above the rib.**

Question 28

on the left hand side of body, where do intercostal veins drain into?

Answer 28

into **hemazygous** **vein** or **accessory hemiazygous** (which then goes into azygous vein)

Question 29

Answer 29

Question 30

where is the cardiophrenic angle? where is the costophrenic angle? where is the

Question 31

what is the nerve supply to: visceral pleura? parietal pleura?

Answer 31

visceral pleura: **autonomic** parietal pleura: **somatic**

Question 32

what is the nerve supply to the i) diaphragmatic pleura? ii) mediastinal pleura?

Answer 32

i) diaphragmatic pleura: **intercostal and phrenic nerves** ii) mediastinal pleura: **phrenic nerve**

Question 33

A simple take home message could be that the **external** **intercostals** are most important to ..... and when they contract they rotate the ribs .... to cause both the .... in anterior-posterior and lateral diameters of the chest wall

Answer 33

A simple take home message could be that the **external** **intercostals** are most important to **respiration** and when the contract they rotate the ribs **upwards** to cause both the **increases** in anterior-posterior and lateral diameters of the chest wall.

Question 35

how does a typical thoracic verebra differ from a cervical and lumbar vertebra? which one of these is a thoracic vertebra?

Answer 35

**Body**: heart-shaped massive that increase in size as descending to the lumbar vertebrae The **body** also has small, smooth, and somewhat **concave costal facets** for the attachment of the ribs. For each of the 12 thoracic vertebrae, there is a **corresponding pair of ribs** attached to them. This is unique since no other vertebrae have ribs attached to them. In addition, the **spinous processes** are relatively **more pointed** than other vertebrae, and **angle sharply downward.** _Answer: the bottom photo: thoracic_

Question 36

where does the intercostal neurovascular bundle lie in relation to: 1) the rib 2) intercostal muscles 3 what is the smaller neurovascular bundle called thats also found in intercostal space?

Answer 36

1) the rib: **the underside of each rib** 2) intercostal muscles: **between internal and innermost intercostal muscles** 3) **collateral branches**

Question 37

role of the pleura? & pleural fluid?

Answer 37

The function of the **pleura** is to al**low optimal expansion and contraction of the lungs during breathing.** The **pleural fluid** acts as a **lubricant**, allowing the **parietal and visceral pleura to glide over each other friction free.** This fluid is produced by the pleural layers themselves.

Question 38

how many lobes are found in right lung? left lung? which ones

Answer 38

right lung: 3 - **superior, middle, inferior** left lung: 2: **superior & inferior**

Question 39

describe the pathway of blood flow from both posterior and anterior intercostal arteries

Answer 39

**posterior IC arteries:** branch from descending thoracic aorta **anterior IC arteries: subclavian arteries pass down to internal thoracic arteries,** which passes down the posterior aspect of the costal cartilages on either side

Question 40

where is the infrasternal angle?

Answer 40

Question 41

in which direction do the fibres of the external intercostal muscles pass? in which direction do the fibres of the internal and innermost intercostal muscles pass?

Answer 41

external intercostal muscles: **downwards and medial** internal and innermost intercostal muscles: **downwards and lateral**