Thoracic Wall

Question 1

Blood supply of thoracic wall

Answer 1

1)Posterior intercostal a
(1-2)&raquo_space; Supreme intercostal artery from costocervical artery
(3-11)» Descending Aorta

2)Subcostal
» Descending aorta

3)Subclavian artery
»Internal thoracic artery
Anterior intercostal a ( + musculophrenic)
»supreme intercostal artery

4) Axillary a
»Superior thoracic artery
»Lateral thoracic artery

Question 2

Internal thoracic artery

Answer 2

Origin: Subclavian artery
Course : at the neck it crosses phrenic nerve on the right and runs lateral and passes the nerve on the left.
Posteriorly : Supraplueral membrane and cervical pluera
Enters thorax : posterior 1st costal cartilage
Runs vertically downward ( lateral to sternum)
Runs Posterior to second costal cartilage to 6th costal cartilage
At the 6th costal cartilage it terminates into two branches: superior epigastric + musculophrenic

Question 3

Xiphisternal joint

Answer 3

Inferior central part of the thoracic cavity
Midline marker : inferior limit of the heart
Superior limit of the liver
Marker of the central tendon of the diaphragm

Question 4

Ribs

Answer 4

1-7» True Ribs
8,9,10» False Ribs
11,12» floating ribs

Question 5

Atypical Ribs

Answer 5

1,2 and 10-12
11+12 have no neck and tubercle. And they also have a single facet

Question 6

Typical Ribs

Answer 6

Head is a wedge with two facets separated by crest.
Neck - connect head and neck
Tubercle - has an articular surface and a non-articular surface
Non-articular: costotransverse ligament
Articular : corresponding transverse process of vertebrae

Question 7

Body

Answer 7

Costal angle&raquo_space;> anterolaterally
Costal groove»> intercostal nerves + blood vessels

Question 8

Borders of thoracic wall

Answer 8

Midline anterior: Sternum
Midline posterior: thoracic vertebrae
Lateral : Ribs and Cartilage
Clavicle + Scapula&raquo_space; shoulder girdle
Intercostal muscles

Question 9

Superior inlet

Answer 9

Small and kidney shaped
Antero: superior border of sternum
Posterior: first thoracic vertebrae
Laterally: 1st Rib with costal cartilage

Question 10

Thoracic outlet

Answer 10

Larger than inlet
Bounded posteriorly : 12th thoracic
Posterolaterally: 11-12 pairs of ribs
Anterolaterally : costal cartilage (7-10)
Anteriorly: xiphisternal joint

Question 11

Venous drainage left side

Answer 11

Intercostal veins.
Posterior intercostal vein : Left side
1- left brachiocephalic via supreme intercostal vein
2-4- left brachiocephalic via the superior intercostal vein
5-8 accessory hemispheres-azygos vein
9-11,12,: hemi-azygos

Question 12

Venous drainage Right side

Answer 12

1- right brachiocephalic via supreme intercostal vein
2-4 - Azygos vein via superior intercostal vein
5-11,12 - azygos vein

Question 13

Anterior venous drainage

Answer 13

*anterior intercostal vein
—»1-6 internal thoracic vein
—»7-11 musculophrenic vein

Question 14

Lymphatic drainage superficial :

Answer 14

Ant + post thoracic wall——> ant and post axillary lymph nodes
Sup to umbilicus plane and iliac plane crest ——> axillary lymph nodes
Inferior to umbilicus ——> inguinal lymph nodes

Question 15

Deep lymphatic drainage

Answer 15

Parasternal lymph nodes - anterior intercostal spaces
Posterior intercostal lymph nodes - posterior intercostal spaces
Diaphragmatic nodes - wall on the periphery of diaphragm

Question 16

Pleura separations

Answer 16

Visceral pleura - attaches onto the lungs
Parietal pleura covers the internal surfaces of the thoracic wall

Question 17

Visceral pleura

Answer 17

Covers lungs
Smooth, slippery and on surface of the lung
Continuous with parietal pleura at the hilum of the lung

Question 18

Parietal pleura

Answer 18

Lines pulmonary cavities divided into 4.
Attach to —mediastinum.
—Thoracic wall
—diaphragm

Question 19

4 subdivisions of parietal pleura

Answer 19

Costal pleura —> lines internal surfaces of the thoracic wall
Mediastinal part —> lines lateral aspects of mediastinum
Diaphragmatic —> lines the superior/ thoracic surface of diaphragm
Cervical—> extends through superior thoracic aperture at the root of the neck . Form cup-shaped pleural dome

Question 20

Endothoracic fascia

Answer 20

It is a thin extraplueral layer of loose connective tissue
It separates costal pleura from the internal surfaces of the thoracic wall