Thoracic cavity and lungs Flashcards
What are the bones of the thorax
thoracic vertebrae, 12 pairs of ribs, sternum
What is the thoracic skeleton
an osseo-cartilaginous cage, containing and protecting the principal organs of respiration and circulation.
What is the infrasternal angle
The angle between the 2 costal arches
What do the costal cartilages of the ribs articulate with
The 1st costal cartilage articulates with the manubrium. The 2nd one articulates with the joint between the manubrium and the body. 3rd – 6th/7th articulate with the body. They are flexible. The lowest 4 costal cartilages (7th, 8th, 9th, 10th) join onto one another in series forming the costal arch
What is a costochondral junction
where cartilages join the ribs
What is the rib classified as
a flat bone
What are the 2 thickenings at the back of the rib and what is it separated by
the head and tubercle, they are separated by the neck
What does the angle of the rib mark
the insertion of the iliocostalis (a back muscle)
Why is the rib hollowed out at the front
for the attachment of the costal cartilages
Why does the inner aspect of the rib have a groove
it is where the intercostal muscles and nerve run
What is the function of the ribs
to protect the organs in the thoracic cavity, assists in respiration, and provides support for the upper extremities
What is a scalene tubercle
feature of atypical rib (scalene = irregular).
Which ribs are the true ribs
. 1-7. Originated from the vertebra and join to the sternum through costal cartilages
Which ribs are the false ribs
Ribs 8,9,10. Originate from vertebra and attach to sternum by joining cartilages of ribs 6 + 7.
Which ribs are the floating ribs
11 + 12. Originate from vertebra but don’t attach anywhere.
Which ribs are the typical ribs
3-9
Which ribs are the atypical ribs
1,2,10,11,12
What are the 3 parts of the sternum
manubrium, the body and xiphoid process
How is the manubrium attached to the body of the sternum
a cartilaginous joint
Where is the sternal angle
angle between the manubrium and the body
What is the joint between the sternum and clavicle called
the sternoclavicular joint
Where does the xiphoid process project in to
downwards in the infrasternal angle
What structures can be found at the sternal angle
joint between T4 and T5, second rib articulation, aortic arch, xygous vein, ligamnetum arterious, left recurrent, laryngeal nerve, bifunction of the pulmonary tongue, bifurcation of the trachea.
What is the inferior thoracic apeture
large opening formed on each side by the costal arch and the last 2 ribs, filled in by the diaphragm
What forms the superior thoracic aperture
The smaller opening at the top which is formed by the manubrium and the first ribs, and the first thoracic vertebra
What does the spine consist of
Consists of 24 vertebrae, the sacrum (5 vertebral segments fused together), and coccyx (consists of ¾ tiny segments).
What does the sacrum articulate with
the 2 innominate bones to form the pelvis.
How many cervical thoracic and lumbar vertebra are there
7 cervical vertebrae, 12 thoracic vertebrae, 5 lumbar vertebrae
What does the vertebral foramen create
a tubular space called the vertebral canal which is what the spinal cord goes through.
What is a pendicle
is a small notch in the upper edge, larger notch in the lower edge
What do the 2 pendicles form
an opening - the intervertebral foramen
What does the neural arch enclose
the spinal cord
What arises from the neural arch
2 x transverse process and 1 spinous process
What is the function of the processes
These protect the spinal cord and give attachment to ligaments an muscles and to articulate with the adjoining vertebrae
What are the 4 articular processes
2 above that face backward, and 2 below that face forward
What forms when the articular processes interlock
a pair of synovial joints which permit movement
What shape is the vertebral foramen in the cervical vertebra
large and triangular
What forms the neural arch in the cervical vertebrae
by 2 straight laminaes
How long are the pedicles on cervical vertebra
short
Describe the spinous process on cervical vertebra
short and ends in a double point
What is the articulate pillar
the mass of bone in between the articulate facets
Where does the transverse process arise on a cervical vertebra
from the side of the body and from the side of the articulate pillar
What is the transverse foramen
The hole in the transverse process which is where the vertebral artery passes
Describe the transverse process on a cervical vertebra
it is shaped like a gutter pointing downwards, ends in an anterior and posterior tubercle (where the scalene muscles attach).
What are the first 2 cervical vertebra called
the atlas and axis
How is the 7th cervical vertebra different from the rest
it has a long spinous process, ending in a single point, forms small prominence on the back of the neck.
Movements of cervical vertebra
flexion, extension, lateral flexion, rotation. Most movement occurs at the joint between the atlas and axis vertebrae.
Why is the cervical vertebra the most mobile part of the spine
due to the curved shape of their bodies
How does the thoracic vertebra articulate with the ribs
it articulates at 2 points; at the end of the transverse process and where the pedicle meets the body.
How do the transverse and spinous process overlap on thoracic vertebra
. The transverse process point sideways, the spinous process point downwards, each one overlapping the one below
Why is their little movement in thoracic vertebra
because of the presence of the ribs and because of the way the spinous processes are arranged
Movements of thoracic vertebra
small amount of forward flexion, lateral flexion and rotation.
How are the external intercostal muscles connected
They extend from the tubercles of the ribs behind, round to the middle of the costal cartilages in front.
What directions do the fibers run in external intercostal muscles
from above, downward
What does action of external intercostal muscles do
produces an upward and forward movement of the anterior chest wall
How do scalene muscles help with inspiration
by moving the first and second ribs and the manubrium
What are the 3 scalene muscles
anterior, middle and posterior
Where does the anterior scalene muscle arise
from the tubercles of the transverse processes from C3 to C6 and inserts on the first rib.
Where does the middle scalene muscle arise
arises from the posterior tubercles of the transverse processes from C2 to C6 and inserts more posteriorly on the first rib
Where does the posterior scalene muscle arise from
from the posterior tubercles from C4 to C6 and inserts on second rib.
Where are the internal intercostal muscles
lie beneath the external ones
What direction do internal intercostal muscles run
runs from slightly left on rib below to slightly right on rib above - runs forward, from below, upward.
What movement do the anterior chest walls create
Moves anterior chest wall downwards and backwards.
How do the muscles of the abdomen effect the pressure and what effect does this have
abdomen raise the intra-abdominal pressure, so push the diaphragm up and pull the lower ribs downwards, assisting the action of the internal intercostal muscles.
Which muscles are present but unimportant during expiration
Levatus of the ribs and the serratus posterior muscles on the outside, and the transversus thoracis and innermost intercostal muscles on the inside
Where is the costal groove
along the inferior margin of the superior rib and pass in between the layer of 2 muscles
What lies in the costal groove
intercostal nerves, associated arteries and veins (VAN)
What is the endothoracic fascia
layer of loose connective tissue
What does the endothoracic fascia separate
separates the nerve, artery and vein from the underlying pleura, it is deep into the intercostal spaces and ribs.
Where does the intercostal nerve pass
laterally around the thoracic wall in an intercostal space
What is the largest branch of the intercostal nerve
The lateral cutaneous branch
Where does the lateral cutaneous nerve pass through
pierces the lateral thoracic wall and divides into an anterior branch and a posterior branch that innervate the overlying skin.
How do the intercostal nerves end
as anterior cutaneous branches , which emerge either parasternally, between adjacent costal cartilages, or laterally to the midline, on the anterior abdominal wall, to supply the skin.
Where do the lungs extend
from the ribs in front to the ribs in back, and from the dome of the pleural cavity, down to the diaphragm
What occupies the space between each lung
the heart, great blood vessels, fat, lymph nodes and in childhood by the thymus gland
What occupies the space between the posterior lungs
the vertebral bodies
What are the 3 surfaces of the lung
The medial/mediastinal surface, concave inferior surface, large convex costal surface
What marks the medial surface of the lung
the hilum, where the bronchi and blood vessels enter
What marks the concave inferior surface
rest of the diaphragm
What marks the large convex costal surface
faces the rib cage
What are the features of the lung
apex, base, oblique fissure and transverse fissure
What are the lobes of the right lung
superior, middle and inferior lobe
What are the lobes of the left lung
superior and inferior lobe
What part of the lung does the visceral pleura cover
completely covers the surface of the lung, except at the hilum where it is continuous with the parietal pleura
Where is the margin of the lung on the mid-clavicular line
6th rib (R), 4th rib (L) with the margin of pleura on the 8th rib.
Where is the margin of the lung on the mid-axillary line
8th rib and the pleura is 10th rib
Where is the margin of the lungs on the mid-scapula line
10th rib with the pleura on the 12th rib
How does the bronchus differ on the right compared to the left
Right principle bronchus, is wider and more vertical.
Why is the recovery position on the left
If someone chokes, then it is more likely to go to the right, so in the recovery position we put someone on to the left.
What is the hilum of the lung
The hilum (root) is a depressed surface at the center of the medial surface of the lung and lies anteriorly to fifth through seventh thoracic vertebrae. Structures enter and leave through the hilum.
Name the structures of the hilum in the left lung from superior to inferior
Pulmonary artery, bronchus, pulmonary veins
Name the structures of the hilum in the right lung from superior to inferior
Bronchus, pulmonary artery, pulmonary veins
What is pulmonary collapse
something has punctured the parietal layer causing air to enter pleural cavity causing the lung to deflate. Can also occur when the lung and visceral pleura is damaged, resulting in air filling the pleural cavity, causing a pneumothorax as well (seen in COPD).
What separates the thoracic cavity into 2 separate cavities
the mediastinum - extends from the vertebral bodies behind, to the sternum in front.
What is in the mediastinum
The heart, great blood vessels, the oesophagus and the trachea
Where is the pleura in the posterior part of the body
Th pleura is reflected off the vertebral bodies, and onto the mediastinum. Behind the sternum, the pleura continues round, onto the front of the chest wall
Where is the pleura located in context of the diaphragm
Below the pleura is reflected off the chest wall and onto the diaphragm, then off the diaphragm into the mediastinum
Where is the pleura located in context to the superior aspect of the mediastinum
Above the pleura fills in the gap that is created by the curvature of the first rib
What is the highest part of the pleura known as
the dome or cupola of the pleura
What happens to the superior part of the pleura when the pressure inside the chest raises
the dome of the pleura is level with the proximal end of the first rib but when pressure increases it raises above the first rib
What happens when the volume of the cavity is increased
the parietal pleura exerts a pull on the visceral pleura, the lung expands and we breathe in.
Describe the pleura at the 1st rib
above the mid point of medial 1/3 of clavicle
Describe the pleura at the second rib
pleura from both sides meet in the mid line
Describe the pleura at the 4th rib
The left side pleura deviates from midline to acommodate the heart
Describe the pleura at the 6th rib
the right sided pleura continue parasternally to 6th rib
What happens to the pleura at the 8th rib
both pleura diverge and cross the mid-clavicular line
What happens to the pleura at the 10th rib
both pleura diverge and cross the mid-axillary line
What happens at the 12th rib
both reach the posterior chest just below the 12th rib
Where are the lungs in relation to the pleura
2 spaces above the pleura
