Flashcards in Test 3 Deck (122):
What are the contents of the thoracic cavity?
Distal part of trachea
What forms the thoracic cage?
the thoracic skeleton
What separates the ribs and their costal cartilages?
the intercostal cartilages
What structure allows for communication between the thoracic cavity and the neck+upper limb?
Superior Thoracic Aperture (the anatomical thoracic inlet)
What are the boundaries of the Superior Thoracic Aperture?
Posteriorly by the T1 vertebra
Laterally by the first pair of ribs and their costal cartilages
Anteriorly by the superior border of the manubrium
What structure allows for communication between the thoracic cavity and the abdomen?
Inferior Thoracic Aperture (the anatomical thoracic outlet)
What structure closes the inferior thoracic cavity and separates the thoracic and abdominal cavities?
What are the boundaries of the Inferior Thoracic Aperture?
Posteriorly by the T12 vertebra
Posterolaterally by the the 11th and 12th pairs of ribs
Anteriolaterally by the joined costal cartilages of ribs 7-10 forming the costal margin
Anteriorly by the xiphisternal joint
What are the 3 types of ribs and what defines them?
True Ribs (vertebrosternal): attaches to the sternum anteriorly through their own costal cartilages
False Ribs (vertebrochondral): have cartilages on the anterior ends that are joined to the cartilage of the rib and so their connection to the sternum is indirect
Floating Ribs (Free): the cartilages on the anterior surface of these ribs cannot attach to the sternum at all
Which ribs are considered true ribs?
1st to 7th ribs
Which ribs are considered false ribs?
8th to 10th ribs
Which ribs are considered floating ribs?
11th and 12th ribs and sometimes 10th rib
What separates the superior and inferior articular facets on a typical rib?
Crest of head
What does the smooth articular part of the tubercle on a typical rib articulate with?
corresponding transverse processes of the vertebra
What attaches at the rough non articular part of the tubercle on a typical rib
the fibrous attachment of the process via the costotransverse ligament
Where is the costal groove located on a typical rib?
on the inferior edge of the body of the rib
What is the purpose of the costal groove?
protects the intercostal nerves and vessels
What are the atypical ribs?
1st, 2nd, and 10th-12th
What does the scalene tubercle separate on the 1st rib?
2 shallow horizontal grooves for the subclavian vessels
What is atypical about the 1st rib?
it is broad and its body is widest and its cross section is more horizontal
What is atypical about the 2nd rib?
it is thinner and it has formations for the attachment of the serratus anterior and posterior scalene muscles
What is atypical about the 10th-12th ribs?
they only have 1 facet on their heads
What is atypical about the 11th and 12th ribs?
they are short have no necks or tubercles
What is the purpose of the costal cartiages?
prolong the rib anteriorly and contribute to the elasticity of the thoracic wall
Where is the subcostal space located?
below the 12th rib
What are the 3 parts of the sternum?
Manubrium, body, and xiphoid process
Which of the 3 parts is the superior part of the sternum?
At what level of the vertebraw does the manubrium lie
at about T3 and T4
Where is the jugular notch located?
Superior border of the manubrium
Where are the clavicular notches located?
on either side of the jugular notch
at which part of the clavicle does the clavicular notch articulate?
What does the body of the sternum articulate with?
Which part of the body of the sternum articulates with the costal cartilages
What type of process is the xiphoid process in young people compared to adults
it is cartilaginous in younger people and it has ossified in adults older than 40 years old
What does the Xiphisternal Joint mark?
it is a midline marker for the superior level of the liver, the central tendon of the diaphragm, and the inferior border of the heart
What are the joints of the thoracic wall?
What vertebral level makes up the body of the sternum?
At what vertebral level is the xiphoid process?
What is the smallest part of the sternum?
How does the thoracic wall move during inspiration?
The intrathoracic diameters and volume of the thorax increase
What happens to the pressure in the thoracic wall during inspiration?
The intrathoracic pressure decreases
How does the thoracic wall move during inspiration?
Intrathoracic diameter and volume decrease
What happens to pressure in the thoracic wall during expiration?
The intrathoracic pressure increases
What happens to the intra-abdominal pressure during expiration?
What happens to the vertical dimensions (height) of the thoracic cavity during inspiration?
It increases as the contracting diaphragm descends and compresses the abdominal viscera
What happens to the vertical dimension of the thoracic cavity during expiration?
It returns to neutral position
What happens to the dimensions of the thoracic cavity during the pump handle movement of the ribs?
The transverse dimension will increase
What is the function of mammary glands in males?
They are functionless and consist of only a few small ducts or cords
What type of glands are mammary glands?
They are modified sweat glands
What produces the volume and contours of the breast?
During pregnancy: enlargement of the mammary glands and formation of new glandular tissue
What causes the growth of breasts in females during puberty?
Glandular development and increased fat deposition
Where does the circular base of the female breast extend horizontally?
From the lateral border of the sternum to the anterior Axillary line
Where does the circular base of the female breast extend vertically?
From the 2nd to 6th ribs
What forms the Axillary process (tail of spence)?
The extension of the breast along the inferolateral edge of the Pectoralis major towards the Axillary fossa
What is the purpose of the retromammary space?
Allows the breast some degree of movement on the deep pectoral fascia
What attaches the mammary glands to the dermis of skin?
Suspensory ligament- these ligaments also help support mammary gland lobules
How many lobules does the breast contain?
What drains the lobules of the breast?
Where does the Lactiferous duct open?
What is the dilation on the end of the Lactiferous duct?
Where is the arterial supply from the breast derived from?
1. Medial mammary branches of perforating branches and anterior intercostal branches of the internal thoracic artery originating from the subclavian artery
2. Mammary branches of the lateral thoracic and thoracoacromial arteries which are branches of the Axillary artery
3. Posterior intercostal arteries which are branches of the thoracic aorta
What vein does the breast drain into?
Mainly the Axillary vein but also the internal thoracic vein
What is the passage of lymph in the breast?
From the lobule of the gland, nipple, and areola to the subareolar lymphatic plexus and from here most lymph drains to the Axillary lymph nodes (mostly the pectoral node)
Where does the lymph from the medial breast quadrants drain?
Parasternal lymph nodes or to the opposite breast
Where does the lymph from the inferior breast quadrants go?
Abdominal lymph nodes (inferior phrenic nodes)
Where does lymph from the Axillary nodes drain?
To the infraclavicular and supraclavicular nodes and from there to the subclavian lymphatic trunk
Where does lymph from the paraintestinal nodes go?
The brachiomediastinal trunk and from there to the thoracic and right lymphatic duct
From where are the nerves of the breast derived?
The anterior and lateral cutaneous branches of the 4th to 6th intercostal nerves
What muscles attach to the thoracic cage?
Pectoralis major and minor, Serratus anterior, latissimus Dorsi
What muscles function as accessory muscles of inspiration?
Pectoralis major and minor, inferior part of the Serratus anterior, and the scalene muscles
What muscles make up the superficial layer of intercostal muscles?
External intercostal muscles
What muscles form the middle layer of intercostal muscles?
Internal intercostal muscles
What muscles form the deepest layer of intercostal muscles?
Innermost intercostal muscles
What forms the intercostal nerves?
the anterior rami of T1-T11
What forms the subcostal nerves?
the anterior rami of the T12 nerve
What are the typical intercostal nerves?
intercostal nerves 3-6
Where do collateral branches of the nerves arise?
near the anterior angles of the ribs and they run along the superior border of the rib below
What do the collateral branches of the nerves give rise to and where?
the lateral cutaneous branches at the midaxillary line
What are the atypical intercostal nerves?
intercostal nerves 1-2 and 7-11
What do the atypical intercostal nerves 7-11 supply?
abdominal skin and muscles
What connects each intercostal and subcostal nerve to the ipsilateral sympathetic trunk?
Where do the arteries of the thoracic wall come from?
the subclavian artery
the axillary artery
What 3 arteries supply each intercostal space?
a large posterior intercostal artery and a pair of small anterior intercostal arteries
Where do the veins of the thoracic wall run?
they run with the intercostal arteries and nerves and are most superior in the costal groove
Where do most posterior intercostal veins end?
azygos/hemi azygos venous system
Where does the venous blood from the azygos/hemi azygos venous system go?
Superior Vena Cava (SVC)
What are the boundaries of the abdominal cavity?
What are the boundaries of the abdominal cavity?
What are the 2 horizontal planes that divide the abdominal region into 9 subregions?
Subcoastal plane- passes through inferior border of 10th costal cartilage on each side
Transtubercular plane- passes through iliac tubercles and the body of the L5 vertebra
What are the 2 vertical planes that divide the abdominal region into 9 subregions?
The 2 midclavicular planes- passes from the midpoint of the clavicles to the midinguinal points
What is the horizontal line that divides the abdominal region into 4 quadrants?
Transumbilical plane- passes through the umbilicus and IV disc between the L3 and L4
What is the longitudinal plane that divides the abdominal region into 4 quadrants?
Median plane- passes longitudinally through the body dividing it into left and right halves
What is the fibrous band that spans between the anterior superior iliac spine and the pubic tubercles and that thickens the external oblique muscle?
How do the fibers of the external oblique run?
Inferomedially and interdigitate with slips of Serratus anterior
How do the fibers of the internal oblique run?
Upper fibers run perpendicular to external oblique
Lower fibers run parallel to the external oblique
How do the fibers of the transversus abdominis run?
What structure encloses the rectus abdominis?
What are the 3 compartments of the thoracic cavity?
2 pulmonary cavities which contain the lungs and pleura
1 mediastinum that contains the heart, great vessels, trachea,esophagus, thymus, and lymph nodes
What are the 4 parts of the parietal pleura?
What encloses each lung?
What makes up the pleural sac?
Visceral and parietal pleura
What ligament extends between the lungs and the mediastinum?
What provides cohesion that keeps the lungs in contact with the pleural wall?
What is the costodiaphragmatic recess?
The area where the pleura of the costal surface comes in contact with the pleura of the diaphragmatic surface
What is the costomediastinal recess?
The space where the pleura of the costal surface comes in contact with the pleura of the mediastinal surface
When do the borders of the lungs move into the costomediastinal and costodiaphragmatic recesses?
During deep inspiration
Which lung has the cardiac notch?
What makes up the anterior border of the lungs?
Where the costal and mediastinal surface meet anteriorly and overlap the heart
What is the inferior border of the lungs?
Where the diaphragmatic surface are separated from the mediastinal and costal surfaces
What is the posterior border of the lungs?
Where the mediastinal and costal surface meet posteriorly
How many branches are at the end of each segmental bronchi?
How many alveolar ducts does each respiratory bronchioles give rise to?
How many alveolar sacs does each alveolar duct give rise to?
What is the basic structural unit of gas exchange in the lungs?
Where does the right bronchial vein drain?
Where does the left bronchial vein drain?
Hemiazygos vein (left superior intercostal vein)
Where are the nerves of the lungs and visceral pleura derived from?
Where are the pulmonary plexuses located?
Anterior and posterior to the root of the lungs and along the branches of the bronchial tree
What kind of cells are located in the pulmonary plexuses?
Parasympathetic ganglion cells
What are parasympathetic ganglion cells?
Cell bodies of post synaptic parasympathetic neurons
What does the fibrous pericardium protect the heart against?