Anatomy Of Thoracic Wall

Question 0

How many ribs are there?

Answer 0

12

Question 1

What is included in the thoracic wall?

Answer 1

Thoracic cage
Muscles between ribs
Skin
Muscles which cover anterolateral wall

Question 2

Which ribs are true ribs? What does this mean?

Answer 2

Ribs 1-7

Connected by costal cartilages to the sternum

Question 3

Which ribs are false ribs? What does this mean?

Answer 3

Ribs 8-10

Connected to the cartilage of the rib above them

Question 4

Which ribs are floating ribs? What does this mean?

Answer 4

Ribs 11 and 12

They end free in abdominal muscle

Question 5

Which ribs are typical ribs?

Answer 5

3-9

Question 6

Structure of typical ribs?

Answer 6

Head has two articular facets separated by a crest
The neck connects the head of the rib with the body
The tubercle is the at the junction of the neck and body.
The body/shaft has a concave surface with a costal groove

Question 7

Function of the articular facets on the head of a true rib?

Answer 7

One facet articulates with the vertebra

The other articulates with the vertebra superior

Question 8

What is the function of the tubercle on a typical rib?

Answer 8

Articulates with the transverse process of the vertebra

Attachment for costotransverse ligament

Question 9

What is the function of the intercostal groove

Answer 9

Provides protection for the intercostal nerve and vessels

Question 10

Which ribs are atypical?

Answer 10

1, 2, 10, 11, 12

Question 11

What makes the first rib atypical?

Answer 11

Very short and board and curved

Has one facet

Question 12

What makes the second rib atypical?

Answer 12

Poorly marked costal groove

Tuberosity for serratus anterior

Question 13

What makes ribs 10, 11 and 12 atypical?

Answer 13

One facet on the head and articulate with a single vertebra

11 and 12 have no tubercle or neck because they are floating

Question 14

What articulates at the costotransverse joint?

Answer 14

Tubercle of rib and transverse costal facet of corresponding vertebra

Question 15

What articulates at the costovertebral joint?

Answer 15

Where head of rib articulates with superior costal facet of the corresponding vertebra and inferior costal facet of the vertebra above
So two for each rib

Question 16

Name the three parts of the sternum

Answer 16

Manubrium
Body
Xiphoid process

Question 17

Features of the manubrium?

Answer 17

Concave
Depression - jugular notch
Fossa lined with cartilage which articulate with clavicle
Facet for articulation with costal cartilage of first rib
Demifacet for second rib

Question 18

Features of the body of the sternum?

Answer 18

Flat and elongated

Lateral edges have many facets

Question 19

Which ribs does the body of the sternum articulate with?

Answer 19

3-6

Has demifacets for articulation with ribs 2 and 7

Question 20

Features of the xiphoid process?

Answer 20

Smallest part of the sternum
Located at T10
Largely cartilaginous - ossified in later life
Articulates with cc of 7th rib

Question 21

Name the intercostal muscles

Answer 21

External intercostals
Internal intercostals
Innermost intercostals

Question 22

How many pairs of external intercostals are there?

Answer 22

11

Question 23

What are the external intercostals continuous with?

Answer 23

The external oblique

Question 24

Innervation of the intercostal muscles?

Answer 24

Intercostal nerves

Question 25

Action of the external intercostals?

Answer 25

Increase volume of thoracic cage during forced inspiration

Question 26

What direction do the external intercostals run?

Answer 26

Inferoanteriorly

Question 27

What direction do the internal intercostals run?

Answer 27

Inferoposteriorly

Question 28

Action of the internal intercostals?

Answer 28

Decrease volume of the thoracic cage during forced expiration

Question 29

What are the innermost ICs and internal ICs separated by?

Answer 29

The intercostal neurovascular bundle

Question 30

Action of the innermost intercostals?

Answer 30

Decrease volume of thoracic cage during forced expiration

Question 31

Where do the transverse thoracic muscles attach?

Answer 31

Originate from lower manubrium and xyphoid process | Attach to costal cartilages of ribs 2-6

Question 32

Innervation of transverse thoracics?

Answer 32

Intercostal nerve

Question 33

Action of the transverse thoracic muscles?

Answer 33

Pull ribs down providing a weak expiratory function

Question 34

Functions of diaphragm?

Answer 34

Separates thoracic cavity from the abdominal | Alters volume of thoracic cavity and lungs

Question 35

Attachments of the diaphragm?

Answer 35

Lumbar vertebrae and arcuate ligaments (L1-3) Costal cartilages of ribs 7-12 Xiphoid process of the sternum Central tendon fuses sign inferior surface of fibrous pericardium

Question 36

Actions of diaphragm?

Answer 36

Inspiration - contracts and flattens, increasing vertical diameter of the thoracic cavity Expiration - diaphragm relaxes and turns to its dome shape

Question 37

Innervation of the diaphragm?

Answer 37

``` Phrenic nerve (left and right) C3, 4, 5 ```

Question 38

Arterial supply of the diaphragm?

Answer 38

Inferior phrenic arteries They arise from the abdominal aorta Superior phrenic, pericardiacophrenic and musculophrenic arteries

Question 39

Venous drainage of the diaphragm?

Answer 39

Inferior phrenic vein Superior phrenic vein Pericardiacophrenic vein Musculophrenic vein

Question 40

Movements of the ribcage?

Answer 40

Upper ribs move in a pump-handle movement to increase anterior-posterior diameter of the thorax Lower ribs move in a bucket handle movement - increases lateral diameter of the thorax

Question 41

What are the three major arteries supplying the thoracic wall?

Answer 41

Thoracic aorta Subclavian artery Axillary artery

Question 42

In the neurovascular bundle, what is the order of structures from top to bottom?

Answer 42

Vein Artery Nerve

Question 43

Where do most of the posterior intercostal veins drain into?

Answer 43

Azygous/hemiazygous venous system to the superior vena cava

Question 44

Where do the two anterior and one posterior intercostal arteries arose from?

Answer 44

Posterior - aorta | Anterior - internal thoracic arteries

Question 45

Where does the internal thoracic artery arise from?

Answer 45

Subclavian

Question 46

Roots of the intercostal nerves?

Answer 46

Anterior rami of T1-T12