Thorax

Question 1

State the 5 functions of the skeleton

Answer 1

1. source of RBC
2. movement
3. protects viscera
4. support
5. contains minerals (acts as reservoir)

Question 2

Which structures make up the axial and appendicular skeleton?

Answer 2

Axial- ribs, skull, vertebrae

Appendicular- limbs

Question 3

State the definition of true, false and floating ribs and allocate which ribs are which?

Answer 3

True- direct articulation to sternum (Ribs 1-7)
False- some anterior connection to other ribs (Ribs 8-10)
Floating- no connection to other ribs or articulation to sternum (Ribs 11 & 12)

Question 4

State the three sections of the sternum.

Answer 4

Manubrium
Sternal body
Xiphoid process

Question 5

State the articulation sites of the vertebrae and what they articulate with.

Answer 5

Demi facets- articulation to rib head
Facets- articulation to rib tubercle
Spinous process (bony projection)- muscles and ligaments of the spine. Inferiorly facing in neck, lumbar and throrax region for maximum movement.
Transverse process (bony projection)- muscles, ligaments and ribs

Question 6

State what is being joined together in

a) costoverterbral joints
b) costotransverse joints
c) intervertebral joints
d) sternocostal joints
e) interchondral joints
f) costochondral joints
g) sternoclavicular joints

Answer 6

a) rib head to demi facet on vertebrae
b) rib tubercle to transverse process
c) between thoracic vertebrae
d) sternum to costal cartilage
e) between adjacent ribs
f) rib to costal cartilage
g) sternum to clavicle

Question 7

How do irregular ribs differ?

Answer 7

They don’t articulate with 2 ribs bandits respective disc,
only one.

E.g. 1st, 11th and 12th

Question 8

Which structures make up the a) superior thoracic aperture and b) inferior thoracic aperture?

Answer 8

a) manubrium, rib 1, T1

b) Xiphoid process, T12 and rib 11&12

Question 9

How does a babies rib cage differ to an adults?

Answer 9

1. protruding xiphoid process
2. horizontal ribs
3. restricted lateral expansion
4. circular chest cavity

Question 10

State the origin, insertion, function and innervation of Pectoralis major.

Answer 10

Clavicle and sternum
Intertubercular sulcus of humerus
Adduction and medial rotation of humerus
Lateral and medial pectoral nerve

Question 11

State the origin, insertion, function and innervation of Pectoralis minor.

Answer 11

Rib 3-5
Corocoid process
Stabilise scapula
Medial pectoral nerve

Question 12

State the origin, insertion, function and innervation of the intercostal muscles.

Answer 12

Ribs 1-11
Varies
Expiration and inspiration
Intercostal nerve in subcostal groove

Question 13

State the origin, insertion, function and innervation of Serratus anterior.

Answer 13

Ribs 1-8
Medial border
Protract scapula
Long thoracic nerve

Question 14

Function of the deltoid muscle?

Answer 14

Abduct humerus

Question 15

State the main arterial supply of the thoracic cage

Answer 15

Thoracic artery - > posterior intercostal artery

Subclavian artery -> anterior intercostal artery

Question 16

State 5 facts about breasts.

Answer 16

1. superficial to pec major
2. glands drain into 15-20 lactiferous ducts
3. Supplied by axillary, internal thoracic and 2nd-4th intercostal arteries
4. Lymph drainage : 75% axillary, 25% parasternal
5. sensation carried by 4th-6th intercostal nerves

Question 17

Describe the movement of abnormal activity between pleura.

Answer 17

Cant pass between pleura because mediastinum completely isolates them

Pleural membranes extend higher than T1 so abnormalities in neck can extend to adjacent pleura.

Question 18

Describe 2 roles of the mediastinum

Answer 18

1. Protect heart, trachea and oesophagus and important blood vessels and nerves
2. Acts as a conduit for phrenic nerves which supply diaphragm, nerves from neck -> abdomen, and major blood vessels en route.

Question 19

Describe the posterior, medial and anterior components of the axillary inlet

Answer 19

Posterior- Scapula
Medial- Rib I
Anterior- Clavicle

Question 20

How do structures that supply the abdomen pass?

Answer 20

Posteriorly or pierce through diaphragm

Question 21

State the 7 reasons why the horizontal plane between T4 T5 is important.

Answer 21

1. marks the point at which the trachea bifurcates
2. distinguishes the superior and inferior mediastinum
3. marks the sternal angle, therefore marks Rib 2
4. marks upper limit of pericardium
5. marks point at which superior Vena Cava penetrates pericardium
6. marks the superior limit of the pulmonary trunk
7. marks where the aorta begins to arch