thoracic wall

Question 1

how many thoracic vertebrae are there

Answer 1

12

Question 2

how many pairs of ribs and costal cartilages are there

Answer 2

12 attached to respective thoracic vertebrae

Question 3

define sternum

Answer 3

breastbone in centre of chest that connects to the ribs via cartilage

Question 4

what are the true ribs and what do they reach

Answer 4

1-7; reach sternum

Question 5

what are the false ribs and what do they reach

Answer 5

8-10; reach costal carilage above

Question 6

what are the floating ribs and why are they called this

Answer 6

11-12; lack anterior attachment

Question 7

what are articulations

Answer 7

joints

Question 8

where are articulations located

Answer 8

with vertebral column via head and tubercle (sticks out of bony structure to provide attachment; facets are where bones join to other bones), and with costal cartilages

Question 9

what is the costal margin

Answer 9

attachment of ribs to diaphragm

Question 10

what is the name of the space between each rib

Answer 10

intercostal space

Question 11

what are the 3 parts of the sternum

Answer 11

manubrium, body, xiphoid

Question 12

where do the 1st costal cartilages attach to on the sternum

Answer 12

manubrium

Question 13

where do the 2nd costal cartilages attach to on the sternum

Answer 13

sternal angle (manubriosternal joint)

Question 14

where do the 3rd-7th costal cartilages attach to on the sternum

Answer 14

sternum

Question 15

where do the 8th-10th costal cartilages attach to on the sternum

Answer 15

cartilage above

Question 16

where do the 11th-12th costal cartilages attach to on the sternum

Answer 16

nothing - they are floating

Question 17

what is the thoracic inlet (superior thoracic aperture) formed of

Answer 17

1st thoracic vertebra (T1), 1st ribs, manubrium

Question 18

what are the contents of the thoracic inlet

Answer 18

great vessels heading for neck and upper limb, oesophagus, trachea, nerves and lymphatics

Question 19

where are most lung tissue and most capacity for lung expansion

Answer 19

lower parts of the thorax

Question 20

what muscles aid in expanding chest and lung volume

Answer 20

diaphragm, intercostal muscles

Question 21

what does the diaphragm consist of

Answer 21

flat central tendon with muscle radiating to costal margin (anteriorly) and crus (posteriorly) and vertebrae

Question 22

diaphragm: first stage of insipiration

Answer 22

dome flattens to inrease vertical diameter of chest

Question 23

diaphragm: second stage of insipiration

Answer 23

pulls costal margin up to increase transverse and antero-posterior diameters

Question 24

what is the secondary role of intercostal muscle

Answer 24

stiffen chest wall to improve efficiency of breathing movements

Question 25

movement of ribs to increase chest volume

Answer 25

ribs move out and up to increase thoracic volume anteroposteriorly and mediolaterally, assisting in changing pressure

Question 26

how many layers of muscles are present in the intercostal muscles, and how are they organised

Answer 26

3, like plywood

Question 27

what are the 3 layers of the intercostal muscles (superficial to deep) and direction

Answer 27

external intercostals (infromedially), internal intercostals (supromedially), innermost intercostals (superior-inferior)

Question 28

external intercostals movement

Answer 28

downward and laterally from lower border of rib above to rib below

Question 29

what are external intercostals replaced by when they move, and where does this happen

Answer 29

anterior intercostal membrane at costo-chondral (rib-cartilage) junction

Question 30

where do internal intercostals attachments begin

Answer 30

anteriorly at sternum

Question 31

internal intercostals movement

Answer 31

from lower border of rib above to rib below

Question 32

how are the fibres directed in internal intercostals

Answer 32

at right angles to external intercostals (hence plywood organisation)

Question 33

what are internal intercostals replaced by

Answer 33

membrane posteriorly

Question 34

what passes close together through internal intercostal near bottom of each rib (superior to inferior)

Answer 34

neurovascular bundle of intercostal vein (run posteriorly and anteriorly), intercostal artery (run posteriorly and anteriorly), intercostal nerve (runs from posterior to anterior)

Question 35

how many pairs of intercostal nerves are there and what are they

Answer 35

11; T1-T11 (+ 1 subcostal T12)

Question 36

what type of nerve are the intercostal nerves

Answer 36

mixed, so motor (efferent at front of roots) and sensory (afferent at back of roots); anterior ramus supplies front, posterior ramus supplies errector spinal muscles and skin

Question 37

where do the intercostal nerves originate from and what do they supply

Answer 37

originate from spinal cord (posterior) and pass through intercostal spaces as they travel towards the anterior, where they innovate muscle and skin

Question 38

what axis does the lateral cutaneous branch innovate

Answer 38

anterior and posterior

Question 39

what axis does the anterior cutaneous branch innovate

Answer 39

medial and lateral

Question 40

border area for inserting a chest drain safely to avoid intercostal vessels and nerve, and avoid important structures

Answer 40

anterior border of latissimus dorsi, lateral border of pectoralis major muscle, line superior to horizontal level of nipple, apex below axilla (armpit); 5th intercostal space anterior to mid axillary line

Question 41

what does each intercostal artery join (anastomose) with

Answer 41

major artery at each end of the intercostal space

Question 42

what are the major internal thoracic arteries

Answer 42

subclavian, which then branch to form internal thoracic, anterior intercostal, maculophrenic, superior epigastric, inferior epigastric and external iliac arteries and veins on anterior chest wall

Question 43

how is the thoracic cavity filled

Answer 43

laterally by lungs

Question 44

where do the lungs lie

Answer 44

own pleural cavity; pair of membranes folded back on itself with fluid between creates surface tension so both layers move out when insipiring; if puncture will move but lung won't inflate

Question 45

what is the space between the pleural cavities called

Answer 45

mediastinum

Question 46

what is present in the mediastinum

Answer 46

heart, great vessels, oesophagus, trachea, thymus, thoracic duct and major lymph trunks, lymph nodes, phrenic and vagus nerves

Question 47

what doe the heart lie in

Answer 47

pericardial sac

Question 48

diagram of the parts of the vertebra

Answer 48

diagram from slide 11 of living anatomy