Thoracic Wall

Question 1

What is the superior thoracic aperture?

Answer 1

Passage of structures between thorax and upper limb/neck

Question 2

What are the boundaries of the superior thoracic aperture?

Answer 2

• Body T1
• 1st pair of ribs and costal cartilage
• superior border of manubrium

Question 3

What is the inferior thoracic aperture?

Answer 3

allows passage of structures between thorax and abdomen

Question 4

what are the boundaries of the inferior thoracic aperture

Answer 4

• body T12
• 11th/12th ribs
• costal cartilage ribs 7-10
• xiphisterna joint

Question 5

How do true ribs connect to sternum (1-7)

Answer 5

connect via own cartilage

Question 6

how to false ribs connect to the sternum (8-10)

Answer 6

connect indirectly via cartilage of ribs above

Question 7

how do floating ribs connect to sternum (11-12)

Answer 7

no connection to thoracic cage

Question 8

describe a the features of a typical rib

Answer 8

• 3rd - 9th rib
• wedge shaped head
• 2 articular facets separated by crest
• neck connects body and head at tubercle
• tubercle with articular and non articular parts
• thin, flat and curved body

Question 9

describe features of the 1st rib (atypical)

Answer 9

• single facet on head
• only articulates with T1
• grooves for subclavian vessels on superior surface
• separated by scalene tubercle

Question 10

describe features of the 2nd rib (atypical)

Answer 10

• rough area on upper surface
• tuberosity for serratus anterior muscle

Question 11

describe the features of the 10th-12th ribs (atypical)

Answer 11

• single facet on head
• articulate with single vertebra
• 11th-12th are short with no neck or tubercle

Question 12

what joints lie between IV discs

Answer 12

2nd degree cartilaginous joints

Question 13

what joints lie between articular facets of vertebrae

Answer 13

synovial plane joints

Question 14

what type of sternocostal joint is at the 1st rib

Answer 14

1st degree cartilaginous joint

Question 15

what type of sternocostal joint is at ribs 2-7

Answer 15

synovial plane joints

Question 16

describe the Interchondral joints of ribs 6-10

Answer 16

synovial plane between 6-9
fibrous between 9-10

Question 17

what is the main muscle of respiration

Answer 17

diaphragm

Question 18

what innervates the diaphragm

Answer 18

Phrenic nerve - anterior rami C3,4,5

Question 19

what are the secondary muscles of respiration

Answer 19

• scalene
• serratus posterior muscles

Question 20

what innervates the pectoralis major?

Answer 20

• medial pectoral nerve (ant. rami C8-T1)
• lateral pectoral nerve (ant rami C5-7)

Question 21

what innervates the pectoralis minor

Answer 21

• medial pectoral nerve (ant. rami C8-T1)

Question 22

what innervates the external oblique

Answer 22

• ant. rami T7-T12

Question 23

what innervates the rectus abdominus

Answer 23

• ant. rami T7-12

Question 24

what innervates the serratus anterior

Answer 24

• long thoracic nerve (ant. rami C5-7)

Question 25

what innervates the anterior scalenes

Answer 25

- ant. rami C3-7

Question 26

what innervates middle scalenes

Answer 26

- ant. rami C4-7

Question 27

what innervates the posterior scalenes

Answer 27

- ant. rami C5-7

Question 28

what innervates serratus posterior superior

Answer 28

- 2nd-5th intercostal nerves

Question 29

what innervates the serratus posterior inferior

Answer 29

- ant. rami T9-12

Question 30

describe the external intercostal muscles

Answer 30

- fibres pass downwards and forwards - from tubercles of ribs to costochondral junction

Question 31

what innervates the external intercostal muscles

Answer 31

- ant. rami T1-11

Question 32

describe the internal intercostal muscles

Answer 32

- fibres pass down and back - from sternum to angle of ribs

Question 33

what innervates the internal intercostal muscles

Answer 33

intercostal nerves

Question 34

describe the innermost intercostal muscles

Answer 34

- deepest layer - fibres pass down and back - very thin - often incomplete

Question 35

what innervates the innermost intercostal muscles

Answer 35

intercostal nerves

Question 36

describe the subcostal muscles

Answer 36

- deep - near angle of ribs - spans 1-2 intercostal spaces

Question 37

what innervates the subcostal muscles

Answer 37

intercostal nerves

Question 38

describe the transversus thoracis

Answer 38

radiates from sides of sternum to costal cartilages 2-6

Question 39

what innervates the transversus thoracis

Answer 39

intercostal nerves

Question 40

where does the neurovascular plane lie

Answer 40

between internal and innermost intercostal muscles

Question 41

what runs in the costal groove

Answer 41

- intercostal Vein - intercostal Artery - intercostal Nerve (VAN)

Question 42

Where does the 1st and 2nd posterior intercostal artery arise from

Answer 42

supreme intercostal artery (branch of costocervical trunk from subclavian artery)

Question 43

where does the 3rd-11th (and subcostal 12th) posterior intercostal artery arise from

Answer 43

thoracic aorta

Question 44

where does the 1st-6th anterior intercostal artery arise from

Answer 44

direct from internal thoracic artery

Question 45

where does the 7-9th anterior intercostal artery arise from

Answer 45

musculophrenic artery

Question 46

describe the venous drainage of the right hand side body wall

Answer 46

- 1st intercostal vein directly into right brachiocephalic vein - rest drain directly into azygos vein

Question 47

describe venous drainage of the left hand side body wall

Answer 47

- veins 1-4 drain into left brachiocephalic vein - veins 5-8 drain directly to accessory hemiazygos vein - veins 9-11 drain to hemiazygos vein

Question 48

describe lymphatic drainage of the thoracic wall

Answer 48

- anterior and lateral body wall drains to anterior and pectoral lymph nodes - posterior chest wall drains to axillary nodes

Question 49

describe arterial supply to the breast

Answer 49

- lateral mammary branches from lateral thoracic artery - medial mammary branches from internal thoracic artery

Question 50

describe venous drainage of the breast

Answer 50

- venous drainage by medial and lateral mammary veins

Question 51

describe the lymphatics of the breast

Answer 51

- 75% to axillary nodes - rest to parasternal nodes