Week 9 Content Flashcards
Name the components of the thoracic cage.
12 thoracic vertebrae posteriorly
12 pairs of ribs and their costal cartilages
Sternum
Describe the facets of thoracic vertebrae.
Facets on the vertebral bodies articulate with the heads of the ribs
Facets on the transverse processes articulate with the rib tubercles
Describe the classification of ribs.
7 pairs of true ribs (1-7)
3 pairs of false ribs - do not directly articulate with the sternum via their own costal cartilage (8-10)
2 pairs of floating ribs - do not articulate with sternum at all (11-12)
Describe the components of a typical rib.
Head with 2 articular facets Neck Tubercle Body or shaft Angle Costal groove
Describe the costovertebral joint.
Articulation of the head of the rib with the superior part of the body of the corresponding thoracic vertebra, the inferior part of the body of the vertebra above, and the IVD
Synovial plane joint
Ligamentous support: radiate ligament (thickening of anterior capsule) surrounding the head of the rib and the 2 bodies of the vertebrae; intra-articular ligament attaches the head of the rib to the IVD
Describe the costotransverse joint.
Articulation of the tubercle of the rib with the associated transverse process\
Synovial plane joint
Ligamentous support: superiorly and laterally supported by the superior and lateral costotransverse ligaments
Describe the costochondral joint.
Articulation of the sternal ends of the ribs with the costal cartilage
Primary cartilaginous joint
Describe the sternocostal joint.
Articulation of the costal cartilages with the manubrium and sternum
1st rib is a primary cartilaginous joint
Ribs 2-7 are synovial plane joints supported by anterior and posterior radiate sternocostal ligaments
Describe how inspiration volume increases.
Vertical increase - contraction of the diaphragm causes the diaphragm to lower
Transverse increase - bucket handle movement of the ribs, primarily by ribs 8-10
Anterior/posterior increase - pump handle movement of the ribs, primarily by ribs 1-7
Name the muscles of the thorax.
Pectorals Serratus anterior Serratus posterior External intercostals Internal intercostals Innermost intercostals Subcostal muscles Transversus thoracis Levatores costorum
Describe the external intercostals.
11 pairs of muscles running obliquely from the rib above to the rib below
Fibers run inferiorly and medially/anteriorly
As they reach the costal cartilages, they become the external intercostal membrane
Muscular posteriorly, membranous anteriorly
Describe the internal intercostals.
11 pairs of muscles lying deep to the external intercostals
Fibers run obliquely at right angles to the external intercostals, run inferiorly and laterally/posteriorly
Posteriorly they form the internal intercostal membrane
Muscular anteriorly, membranous posteriorly
Describe the innermost intercostals.
11 pairs of muscles that run similar to the internal intercostals (inferolaterally)
Separated from the internal intercostals by the intercostal nerves and vessels
Muscular in the middle 3/4 of the intercostal space
Describe the subcostal muscles.
Thin muscular slips that extend from the angle of a rib on the internal surface to internal surface of rib below, crossing 2 intercostal spaces
Fibers run in the same direction as internal intercostals (inferolaterally)
Describe the transverse thoracis.
4 or 5 muscular slips that arise from the xiphoid and body of the sternum, spanning superiorly and laterally to costal cartilages 2-6
Describe levatores costarum.
12 fan-shaped muscles arising from the transverse processes of C7-T11, inserting inferiorly and laterally on the ribs below
Describe the intercostal nerves.
Ventral primary rami of the first 11 thoracic spinal nerves
12th thoracic spinal nerve is called the subcostal nerve
Describe the intercostal arteries.
Each intercostal space is supplied by a large posterior intercostal artery arising from the aorta and a small anterior intercostal artery arising from the internal thoracic artery, which arises from the subclavian artery
Describe the 2 pleura of the lungs.
Visceral pleura lines the lungs, parietal pleura lines the walls of the thoracic cavity. They come together and become continuous at the root of the lung
Parietal pleura has 3 parts - costal pleura (lines thoracic walls), diaphragmatic pleura (lines the diaphragm), and mediastinal pleura (lines the mediastinum)
Pleura cavities are 2 separate and closed potential spaces filled with fluid to reduce friction between parietal and visceral pleura
Describe the right and left lungs and their fissures.
Right lung has 3 lobes - superior, middle, and inferior - separated by horizontal and oblique fissures
Left lung has 2 lobes - superior and inferior - separated by an oblique fissure
Describe the bronchial tree.
Each lung receives a primary or principal bronchus from the trachea.
Each principal bronchus then divides into lobar bronchi which each supply a lobe of the lung.
Each lobar bronchus then divides into tertiary segmental bronchi, which each supply a specific bronchopulmonary segment.
Describe the arterial supply to the lungs.
The branches of the pulmonary arteries supply venous blood to the lungs for aeration
Pulmonary arteries run with the bronchi and lie posterior to them
Each lobe and bronchopulmonary segment has a branch
Bronchopulmonary segments have no arterial anastomoses, SO removal of a pulmonary segment of the lung will not endanger the viability of adjacent segments
Describe the venous supply of the lungs.
Pulmonary vein drains oxygenated blood to the left atrium of the heart
Superior and inferior pulmonary veins are formed at the hilus of each lung
Superior pulmonary veins receive from the superior and middle lobes of the right lung and superior and lingula lobes of the left lung
Inferior pulmonary veins receive from the lower lobes of the right and left lungs
What is the root of the lung?
AKA the hilum of the lung, it is the attachment point of the lung to the heart and trachea, surrounded by the reflection of the parietal to visceral pleura
Provides a highway for the main bronchus, pulmonary vessels, bronchial vessels, lymph vessels, and nerves
Describe lymphatic drainage of the lungs.
Superficial lymphatic ducts drain to the surface and runs along the visceral pleura to the hilum
Deep lymphatic drainage follows the bronchi and collects at the hilum
At the hilum, all the lymphatic drainage is filtered by the tracheobronchial nodes
How does the parietal pleura relate to the thoracic wall?
Superiorly, pleura extends through thoracic inlet and is called the cupula
Inferiorly: 7th costal cartilage anteriorly, 10th costal cartilage mid-axillary, and 12th vertebral level posteriorly