Thorax 1

Question 1

List the functions of the thorax

Answer 1

Protection, Rigidity and elasticity, respirtaion, locomotion as it allows attachment for muscles, heamatopoiesis and connections with neck, UL and abdo

Question 2

Describe what makes the thorax

Answer 2

Thoracic cage - Sternum, 12 pairs of ribs, 12 thoracic vertebrate and IV discs.

Thoracic wall - Thoracic cage, skin, subcutaneous tissue, 3 layers of intercostal muscles and breast tissue

Question 3

Name the true, false and floating ribs.

Answer 3

True = Ribs 1-7, these attach directly to sternum via costal cartilage (CC)
False = Ribs 8-10, attach indirectly via the CC of rib 7
Floating = Ribs 11-12, do not articulate with sternum

Question 4

Name the typical ribs and their features

Answer 4

Ribs 2-10. They have a head, neck, tubercle, body, costal angel and costal groove ( on the inner surface near inferior boarder, passage of intercostal vessels and nerve)

Question 5

Describe the features of the atypical rib 1

Answer 5

Scalene tubercle for attachment of anterior scalene muscle, groove for subclavian artery, vein and inferior trunk of brachial plexus, articulates with T1 only, no costal groove and cannot be palpated

Question 6

Describe features of the floating ribs

Answer 6

Does not attach to sternum, heads only articulate with corresponding vertebra and they do not articulate with transverse processes.

Question 7

The sternal angle is at the level of…what?

Answer 7

• 2nd CC
• IV disc between T4 and T5
• Prox and distal boarders of aortic arch
• Bification of trachea
• Superior limit of pulmonary trunk
• Azygos opening into SVC
• ligamentum ateriosum

Question 8

Why is the sternum important?

Answer 8

Because it is a site of blood cell production so is one of the sites for bone marrow aspiration.

Question 9

Where is the T6 dermatome located?

Answer 9

Solar plexus region which is the Xiphoid region

Question 10

Describe features of the costovertebral joint

Answer 10

Ribs 2-10 articulate with superior costal facet of corresponding vertebra and the inferior costal facet of vertebra above. Synovial joints supported by capsule with ligaments.

Question 11

Describe the costal facets of the thoracic vertebrae

Answer 11

T1 - 1 and 1/2 costal facets.
T2 -T9 have 2 half costal facets
T10 has 1 half costal facets.
T11 and T12 have 1 oval costal facet

Question 12

Describe features of the costotransverse joint

Answer 12

Joint between rib tuberce on ribs 1-10 and the transverse process of corresponding vertebrate. Costotransverse joints 1-7 have curved facets allowing for rotation but joints 8-10 have flat facets allowing for gliding.

Question 13

Describe features of the costochondral joints and the costosternal joints

Answer 13

All ribs articulate with a CC via a primary cartilaginous joint. The CC of ribs 1-7 articulate directly with sternum but 8-10 articulate with the CC above

Question 14

Describe the shapes of the CC

Answer 14

Ribs 1 - 4 have horizonal CCs while the shape of the CCs for ribs 5-10 increase in their oblique direction. Significant in respiration

Question 15

Describe features of the thoracic inlet (superior aperture)

Answer 15

Bound by T1, first rib and its CC and the manubrium. It sloaps antero-inferiorly to the level of T2/3 and the lung extends 2/3 cm above the anterior part of 1st rib.

Question 16

What structures pass between the thorax and the neck, and the thorax and the UL?

Answer 16

Neck - Vessels, trachea, oesophagus, vagus and recurrent laryngeal nerves and the phrenic nerve.

UL- Subclavian vein, artery and inferior trunk of brachial plexus

Question 17

What is the thoracic outlet bound by?

Answer 17

T12, 11th and 12th ribs, the CC’s of ribs 7-10, the xiphoid process and it is closed incompletely by the diaphragm.

Question 18

What is thoracic outlet syndrome?

Answer 18

Where the brachial plexus and the subclavian vein and artery can be compressed as they are closely related to the 1st rib and inferior surface of clavical.

Question 19

Name the common sites of compression during thoracic outlet syndrome

Answer 19

Scalene triangle, Costoclavicular site and the subpectoral space.

Question 20

What are breasts?

Answer 20

Accessory glands consisting of mammary glands, skin and connective tissue. They consist of 15-25 lobes formed from lobules and ducts

Question 21

What are montgomery tubercles?

Answer 21

Visible sebaceous glands on the surface of the areola

Question 22

Where does the base of the breast lie?

Answer 22

At the levels of the 2nd to 6th rib, from the lateral boarder of the sternum to the axilla

Question 23

What is the axillary process?

Answer 23

Axillary tail of spence is upper lateral breast tissue that extends to the axilla, it may even perforate the deep fascia.

Question 24

Where is the breast tissue found?

Answer 24

Between the deep and superfical layers of the superficial fascia. It sits on pec major, serratus anterior and external oblique muscle.

Question 25

What are cooper’s ligamnets? and their function

Answer 25

Condense connective tissue that forms suspensory ligaments of the breast, they connect deep fascia to the dermis and support the breast

Question 26

What is the retromammary space and what is its function?

Answer 26

It is a layer of loose connective tissue between the deep layer of superficial fascia and the deep fascia. It allows for movement of the breast over underlying tissue.

Question 27

Describe the vascular supply of the breast

Answer 27

From the internal thoracic artery are mammary branches and anterior intercostal arteries that supply the breast as well as the lateral thoracic artery and the thoraco-acromial artery from the axillary artery.

Question 28

Veins of the breast mainly drain to where?

Answer 28

The axillary vein and the internal thoracic vein

Question 29

Describe the lymphatic drainage of the breast

Answer 29

Areola and lateral quadrents to axillary LN.
Medial quadrents to parasternal LN.
Inferior quadrents to inferior phrenic LN