Thoracic Wall Flashcards
Blood supply of thoracic wall
1)Posterior intercostal a
(1-2)»_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
Internal thoracic artery
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
Xiphisternal joint
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
Ribs
1-7» True Ribs
8,9,10» False Ribs
11,12» floating ribs
Atypical Ribs
1,2 and 10-12
11+12 have no neck and tubercle. And they also have a single facet
Typical Ribs
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
Body
Costal angle»_space;> anterolaterally
Costal groove»> intercostal nerves + blood vessels
Borders of thoracic wall
Midline anterior: Sternum
Midline posterior: thoracic vertebrae
Lateral : Ribs and Cartilage
Clavicle + Scapula»_space; shoulder girdle
Intercostal muscles
Superior inlet
Small and kidney shaped
Antero: superior border of sternum
Posterior: first thoracic vertebrae
Laterally: 1st Rib with costal cartilage
Thoracic outlet
Larger than inlet
Bounded posteriorly : 12th thoracic
Posterolaterally: 11-12 pairs of ribs
Anterolaterally : costal cartilage (7-10)
Anteriorly: xiphisternal joint
Venous drainage left side
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
Venous drainage Right side
1- right brachiocephalic via supreme intercostal vein
2-4 - Azygos vein via superior intercostal vein
5-11,12 - azygos vein
Anterior venous drainage
*anterior intercostal vein
—»1-6 internal thoracic vein
—»7-11 musculophrenic vein
Lymphatic drainage superficial :
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
Deep lymphatic drainage
Parasternal lymph nodes - anterior intercostal spaces
Posterior intercostal lymph nodes - posterior intercostal spaces
Diaphragmatic nodes - wall on the periphery of diaphragm
Pleura separations
Visceral pleura - attaches onto the lungs
Parietal pleura covers the internal surfaces of the thoracic wall
Visceral pleura
Covers lungs
Smooth, slippery and on surface of the lung
Continuous with parietal pleura at the hilum of the lung
Parietal pleura
Lines pulmonary cavities divided into 4.
Attach to —mediastinum.
—Thoracic wall
—diaphragm
4 subdivisions of parietal pleura
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
Endothoracic fascia
It is a thin extraplueral layer of loose connective tissue
It separates costal pleura from the internal surfaces of the thoracic wall
