Thoracic Cage

Question 1

What 3 parts are sternum composed of:

Answer 1

Manubrium, body, xiphoid process

Question 2

What is the angle of Louis/ sternal angle

Answer 2

The point where the manubrium and body articulate at a manubriosternal joint- level of 2nd rib/T4

Question 3

Suprasternal (jugular) notch

Answer 3

Notch in superior border of manubrium

Question 4

How many pairs of ribs

Answer 4

12 angled downwards from back to front

Question 5

What is the costal margin

Answer 5

The 7, 8, 9, 10th costal cartilage join to one another

Question 6

Costochondral joint

Answer 6

Point where rib and costal cartilage articulate

Question 7

Sternocostal joint

Answer 7

Costal cartilage and sternum articulate

Question 8

Costovertebral joint

Answer 8

Ribs and thoracic vertebrae articulate

Question 9

Typical ribs

Answer 9

Thin, flat, curved in a spiral
Ribs 3-9
Have a head, neck, body, tubercle

Question 10

Number of thoracic vertebrae

Answer 10

12

Question 11

Which ligaments hold the joints of the vertebrae together

Answer 11

Radiate ligament and superior costotransverse ligament

Question 12

Synovial joints between vertebrae

Answer 12

• Head of rib articulates with vertebral body - head has 2 articular facets
  • Tubercle of rib articulates with transverse process of vertebra (costotransverse joint)

Question 13

3 types of intercostal muscle

Answer 13

External, internal, innermost

Question 14

External intercostal muscle

Answer 14

fibres are orientated antero-inferiorly
• contraction pulls ribs superiorly- most active in inspiration
• In anterior part of intercostal space, muscle becomes membranous and forms the external intercostal membrane

Question 15

Internal intercostal muscle

Answer 15

fibres run perpendicular to external intercostal in a postero-inferior direction
• Contraction pulls ribs inferiorly- most active in expiration
• Internal intercostal becomes membranous in posterior path of intercostal space and forms the internal intercostal membrne

Question 16

Innermost intercostal muscle

Answer 16

lies in posterior part of intercostal space
• Fibres orientated in same direction of internal intercostal

Question 17

Endothoracic fascia

Answer 17

Lies deep to innermost intercostal but superficial to parietal pleura

Question 18

Where does the intercostal neurovascular bundle lie

Answer 18

In between the internal and innermost intercostal muscle

Lies along the inferior border of the rib superior to the space in a shallow costal groove on deep surface of rib

Question 19

Intercostal nerves

Answer 19

Somatic and contain motor and sensory fibres
Also carry sympathetic fibres
Innervate the intercostal muscles, the skin of the chest wall and the parietal pleura

Question 20

What is the anterior intercostal artery branched from

Answer 20

Internal thoracic artery (branches from subclavian artery)

Question 21

What is the posterior intercostal artery branched from

Answer 21

Descending aorta in posterior thorax

Question 22

What do anterior thoracic veins drain into

Answer 22

Internal thoracic vein

Question 23

What do posterior thoracic veins drain into

Answer 23

Azygos system of veins

Question 24

What does the intercostal neurovascular bundle supply

Answer 24

intercostal muscles, overlying skin and underlying parietal pleura

Question 25

Thoracic cage is semi-rigid

Answer 25

costal cartilage that forms a flexible, springy ridge

Question 26

Superior thoracic aperture

Answer 26

Manubrium, first ribs and first thoracic vertebra form boundary of superior thoracic aperture- passageway through which structures pass between neck and thorax

Question 27

The suprasternal notch is a feature of which bone?

Answer 27

Manubrium

Question 28

Intervertebral discs

Answer 28

The bodies of adjacent vertebrae are separated and united by an intervertebral disc, which provides padding and allows for movements between adjacent vertebrae. The disc consists of a fibrous outer layer called the anulus fibrosus and a gel-like center called the nucleus pulposus.

Question 29

Anulus fibrosus

Answer 29

Outer fibrous layer of intervertebral disc Chondrocytes present In the outer casing strong bands of collagen fibres are evident

Question 30

Nucleus polposus

Answer 30

Gel-like centre of intervertebral disc Chondrocytes present at the centre the collagen is more evenly dispersed.

Question 31

What are the articular surfaces of the vertebra covered by

Answer 31

Hyaline cartilage

Question 32

Where do the posterior intercostal arteries originate from

Answer 32

originate from the superior (supreme) intercostal artery, a branch of the costocervical trunk. Third to eleventh posterior intercostal arteries arise directly from the posterior surface of the thoracic aorta.

Question 33

what feature of the rib protects the neurovascular bundle

Answer 33

Costal groove

Question 34

Number of posterior intercostal arteries

Answer 34

11

Question 35

Number of anterior intercostal arteries

Answer 35

9

Question 36

Where do anterior intercostal arteries originate from

Answer 36

The 1st to 6th anterior intercostal arteries arise directly from the lateral aspect of the internal thoracic artery. The 7th to 9th arise from the musculophrenic artery, a branch of the internal thoracic artery.

Question 37

Importance of the sternal angle RATPLANT

Answer 37

Rib - 2nd Aortic arch Trachea bifurcation Pulmonary trunk bifurcation Left recurrent laryngeal loops under aorta + Ligamentum arteriosum Azygos vein drains into superior vena cava Nerve- cardiac plexus Thoracic duct empties into left subclavian vein

Question 38

Parts of scapula from top to bottom

Answer 38

Acromion Coracoid process Glenoid fossa Supraspinous fossa Infraspinous fossa

Question 39

Dermatome of suprapubic region

Answer 39

T12

Question 40

Muscles of thoracic wall superficial to deep

Answer 40

Pectoralis major Pectoralis minor Serratus anterior External intercostal Internal intercostal Innermost intercostal

Question 41

Dermatome level of shoulder

Answer 41

C5

Question 42

Action of serratus anterior muscle

Answer 42

Protract the scapula

Question 43

Serratus anterior is supplied by which nerve

Answer 43

Long thoracic nerve

Question 44

Which vein drains the posterior thoracic wall into the superior vena cava?

Answer 44

Azygos