Anatomy - the thorax

Question 1

where is the thorax?

Answer 1

located between the neck and abdomen

Question 2

what is contained within the thorax?

Answer 2

thoracic cavity contains the lungs and heart
also contains the major blood vessels, part of the trachea and oesophagus

Question 3

what protects the contents of the thoracic cavity?

Answer 3

thoracic wall

Question 4

what are the functions of the thorax?

Answer 4

respiration
protection
conduit (passageway)

Question 5

what Is the shape of the thorax?

Answer 5

narrower at top and wider at the bottom
goes from the neck to the abdomen

Question 6

what does the thoracic wall consist of?

Answer 6

-sternum
-thoracic vertebrae (T1-T12)
-ribs and costal cartilages
-intercostal muscles fill the intercostal spaces
-arteries and nerves that supply it

Question 7

are the pectoral muscles part of the thoracic wall?

Answer 7

no they are considered upper limb muscles

Question 8

what makes up the thoracic cage?

Answer 8

skeletal framework, bone and cartilage

Question 9

what is the thoracic cage?

Answer 9

provides rigidity and flexibility

Question 10

what kind of joints are between the vertebrae and the ribs?

Answer 10

synovial plane joints so allow some movement

Question 11

what are the true ribs?

Answer 11

costal cartilage attaches directly to the sternum - sternocostal joints

Question 12

what are false ribs?

Answer 12

costal cartilage attaches to the cartilage above - interchondral joints (ribs 8-10)

Question 13

what are floating ribs?

Answer 13

do not attach to the sternum at all (11+12)

Question 14

what are the costovertebral joints?

Answer 14

head of the rib articulates with the superior Demi-facet of the corresponding vertebra and the inferior Demi-facet of the vertebrae superior to it

Question 14

what is the costotransverse joint?

Answer 14

the tubercle of the rub articulates with the transverse process of the corresponding vertebra

Question 15

where does the rib joint on to the spine?

Answer 15

between 2 vertebrae, joins via Demi-facets

Question 15

which ribs are atypical in terms of joints?

Answer 15

1, 10, 12
rib 1 - head only articulates with T1
10 and 12 don’t have demi facets only articulate with one vertebra

Question 16

what is the superior thoracic aperture?

Answer 16

the doorway between the thoracic cavity and the neck and upper limb

Question 17

what is the inferior thoracic aperture?

Answer 17

provides attachment for the diaphragm

Question 18

what separates the thoracic and abdominal cavities?

Answer 18

diaphragm

Question 19

what clinical problems can cervicle ribs cause?

Answer 19

sometimes also have a cervical band of tissue that extends anteriorly, structures passing through the thorax can be interrupted by this cervical band
brachial plexus and axillary can be affected

Question 19

what are the boundaries of the superior thoracic aperture?

Answer 19

bones and cartilage of thoracic cage, - T1, medial border of rib one on either side and superior border od manubrium

Question 20

what are the attachments of the diaphragm?

Answer 20

L1-L3 vertebrae
inferior costal cartilages and adjacent ribs
xiphoid process

Question 21

what is the principle muscle of respiration?

Answer 21

diaphragm

Question 22

how much can the domes of the diaphragm project upwards?

Answer 22

reach the level of the 5th rib

Question 23

what is the nerve innervation of the diaphragm?

Answer 23

phrenic nerve, C3-5 C3,4,5 keep the diaphragm alive

Question 23

why is the right dome of the diaphragm higher than the left?

Answer 23

the liver sits here

Question 24

which kidney sits higher?

Answer 24

the left kidney

Question 25

how much does the diaphragm move during quiet breathing?

Answer 25

1-2cm

Question 26

what happens to the diaphragm when we breathe in?

Answer 26

it contracts, flattens out to increase space in thoracic cavity

Question 27

how much does the diaphragm move during forced breathing?

Answer 27

6-10cm

Question 28

where do the muscle fibres of the diagram insert?

Answer 28

the inferior thoracicapeture margins

Question 29

what is the thoracic cavity?

Answer 29

a conduit passageway, from throat, neck to abdomen

Question 30

what is the caval opening?

Answer 30

hole in the central tendon,

Question 31

what passes through the caval opening?

Answer 31

inferior vena cava at level of T8

Question 32

what passes through the diaphragm at the level of T10?

Answer 32

oesophagus, throighthe oesophageal hiatus (in the muscle of the diaphragm)

Question 33

when and where does the aorta pass through the diaphragm?

Answer 33

at T12 through the aortic hiatus. behind the diaphragm

Question 34

what are the external intercostal muscles?

Answer 34

occupy intercostal spaces from posterior to costochondral junction muscle fibres run anterioinferiorly

Question 35

when are the external intercostals most active?

Answer 35

during inspiration when they contract they lift the ribs up

Question 36

when are the internal intercostals most active?

Answer 36

during expiration when they contract they depress the ribs

Question 37

what are the internal intercostal muscles?

Answer 37

occupy the intercostal spaces from anterior to angle of the ribs muscle fibres run anteroposteriorly

Question 38

what are the innermost intercostal muscles?

Answer 38

deep part of internal intercostal muscles form an incomplete layer that is most obvious laterally

Question 39

where do the intercostal neuromuscular bundles lie?

Answer 39

lie between internal and innermost intercostals

Question 40

how do the ribs move when breathing?

Answer 40

they slope inferiorly therefor elevation of the ribs increases the anterioposterior lateral dimensions of the thorax contraction of the diaphragm increases the superoinferior dimensions

Question 41

what Are some accessory muscles of respiration?

Answer 41

sternocloidimastoid (from skull down to clavicle) pectoris muscles

Question 42

how can accessory muscles help with respiration?

Answer 42

fixing of the arm and pectoral girdle allows neck and arm muscles to assist rib elevation in forced breathing

Question 43

which muscles can assist forced expiration?

Answer 43

abdominal muscles

Question 44

what is the order from top to bottom of the intercostal neuromuscular bundle?

Answer 44

vein, artery, nerve VAN

Question 45

what is the groove called that the intercostal neuromuscular bundle sits?

Answer 45

subcostal groove

Question 46

what is the smaller bundle called that sits superior to the rib called?

Answer 46

collateral branches

Question 47

what roots form the intercostal nerves?

Answer 47

anterior rami of T1-T11

Question 48

what spinal nerve form the subcostal nerve?

Answer 48

the anterior ramus of T12

Question 49

what are the 2 branches of intercostal arteries?

Answer 49

anterior and posterior they anastomose - important in establishing a collateral blood supply

Question 50

where do the posterior intercostal arteries originate from?

Answer 50

aorta

Question 51

where does the anterior intercostal artery originate from?

Answer 51

internal thoracic artery (or its branches)

Question 52

where does the internal thoracic artery originate from?

Answer 52

subclavian artery

Question 53

internal thoracic artery?

Answer 53

bifurcates into musculophrenic and superior epigastric arteries

Question 54

what happens if there is a stricture or damage to the proximal aorta?

Answer 54

internal thoracic arteries and anterior intercostal arteries can expand to maintain blood supply

Question 55

what does the musculofrenic artery supply?

Answer 55

diaphragm

Question 56

what does the superior epigastric artery supply?

Answer 56

skin over proximal abdominal wall

Question 57

what are the 3 subdivisions of the thoracic cavity?

Answer 57

pulmonary cavity mediastinum pulmonary cavity

Question 58

what are the pulmonary cavities?

Answer 58

contain the lungs, completely separate

Question 59

what is in the mediastinum?

Answer 59

the heart

Question 60

what are the layers of the pericardium?

Answer 60

visceral layer, serous pericardium parietal layer, serous pericardium fibrous pericardium - forms sac around heart

Question 61

what are the layers around the lungs (pleura)?

Answer 61

parietal pleura - connecte tissue layer visceral pleura - closely associated with the thoracic wall

Question 62

what are the pleural recesses?

Answer 62

potential spaces between the costal and diaphragmatic pleura that the lungs can move into during inspiration

Question 63

what are serous membranes?

Answer 63

as an organ develops it pushes into a serous membrane which is like a water balloon. the outermost layer is the visceral layer, the farther away part is the parietal. there is a layer of fluid between the layers which lubricates layers are continuous which represents blood vessels ect

Question 64

what is the most important recess?

Answer 64

the costodiapragmatic recess as its most likely where fluid will pool

Question 65

between which muscles does the neuruvascular bundles lie?

Answer 65

internal and innermost intercostal muscles

Question 66

what is the safest route to insert a needle to perform thoracentesis?

Answer 66

costodriaphragmatic recess, superiori to rib, just high enough to avoid collateral bundle branches of intercostal nerve

Question 67

what is a thoracotomy?

Answer 67

surgical procedure used to gain access into the pleural space

Question 68

why is the 1st rib rarely fractured?

Answer 68

protected very well

Question 69

what would happen with a spinal cord injury of C7?

Answer 69

Someone with a C6 – C7 injury is likely to still have some impaired diaphragmatic control, using accessory muscles of the back and chest more than someone without SC

Question 70

what is the safest route of a thorocentesis?

Answer 70

The preferred site for the procedure is on the affected side in either the midaxillary line if the procedure is being performed in the supine position or the posterior midscapular line if the procedure is being performed in the upright or seated position