PRELIMS - THORAX: CONCEPTUAL OVERVIEW Flashcards
Ain irregularly shaped cylinder that is composed of two apertures
THORAX
An aperture of the thorax that has a narrow opening and lies superiorly.
It is open and allows continuity with the neck
SUPERIORTHORACIC APERTURE
An aperture of the thorax that has a relatively large opening and lies inferiorly.
closed by the Diaphragm
INFERIOR THORACIC APERTURE
Part of the thorax that is flexible and consists of segmentally arranged vertebrae, ribs, muscles and sternum.
MUSCULOSKELETAL WALL OF THORAX
Part of the thorax that is enclosed by the thoracic wall and the Diaphragm
THORACIC WALL
What are the 3 major compartments of the thoracic cavity
~LEFT PLEURAL CAVITY
~RIGHT PLEURAL CAVITY
~MEDIASTINUM
A compartment of the thoracic cavity that is thick, flexible soft tissue partition oriented longitudinally in a median sagittal position.
It can also be entered surgically without opening the pleural cavities.
MEDIASTINUM
Organs contained by the mediastinum
~HEART ~ESOPHAGUS ~TRACHEA ~MAJOR NERVES ~MAJOR SYSTEMIC BLOOD VESSELS
The mediastinum separates this into two equal parts
PLEURAL CAVITIES
the pleural cavity can extend up to what part of the rib?
ABOVE THE LEVEL OF RIB 1
What are the functions of the thorax?
~BREATHING
~PROTECTION OF VITAL ORGANS
~CONDUIT
What is the most important function of the thorax?
BREATHING
What are the machineries necessary for breathing that are used in effectively moving air into and out of the lungs
~DIAPHRAGM
~THORACIC WALL
~RIBS
What are the results that happen because of the movements of the ribs
UP AND DOWN MOVEMENT OF THE DIAPHRAGM
CHANGES IN LATERAL AND ANTERIOR DIMENSIONS OF THE THORACIC WALL
Key elements in breathing
ALTERATION OF THE VOLUME OF THE THORACIC CAVITY
What are the organs that are housed and protected by the thorax?
~HEART
~LUNGS
~GREAT VESSELS
What is the shape of the diaphragm?
UPWARD DOME SHAPED DIAPHRAGM
Where does most of the liver lies in the thorax?
UNDER THE RIGHT DOME OF THE DIAPHRAGM
Where does the stomach and spleen lies in the thorax?
UNDER THE LEFT DOME OF THE DIAPHRAGM
Where does the posterior aspects of the superior poles of the kidneys lie on the thorax?
DIAPHRAGM AND IS ANTERIOR TO THE RIB 12 ON THE RIGHT AND RIB 11 AND 12 ON THE LEFT
It acts as a conduit for structures that pass completely through the thorax from one body region to another, and for structures that connect organs in the thorax to other body regions
MEDIASTINUM
Passes through the mediastinum as they course between the abdomen and neck
~ESOPHAGUS
~VAGUS NERVE
~THORACIC DUCT
Passes through the mediastinum to penetrate and supply the diaphragm
PHRENIC NERVES
Where does phrenic nerves originate from?
NECK
Structures that courses within the mediastinum to and from major visceral organs in the thorax
~TRACHEA
~THORACIC AORTA
~SUPERIOR VENA CAVA
What are the component parts of the thorax?
~THORACIC WALL ~SUPERIORTHORACIC APERTURE ~INFERIOR THORACIC APERTURE ~DIAPHRAGM ~MEDIASTINUM
A component part of the thorax that is composed of skeletal elements and muscles
THORACIC WALL
What is the thoracic wall made up of posteriorly?
~12 THORACIC VERTEBRAE
INTERVENING ~INTERVERTEBRAL DISCS
What is the thoracic wall made up of laterally?
~12 PAIRS OF RIBS
~3 LAYERS OF FLAT MUSCLES
What is the thoracic wall made up of anteriorly?
STERNUM
What are the parts of the sternum?
~MANUBRIUM OFTHESTERNUM
~BODY OF STERNUM
~XIPHOID PROCESS
A part of the sternum that is angled posteriorly on the body of the sternum at the manubriosternal joint
MANUBRIUM OF STERNUM
It forms the sternal angle
MANUBRIOSTERNAL JOINTS
A major surface landmark used by clinicians in performing physical examinations of the thorax
STERNAL ANGLE
The anterior end of each rib is composed of what type of cartilage?
it also contributes to the mobility and elasticity of the thoracic wall
COSTAL CARTILAGE
These articulates with the thoracic vertebrae posteriorly
ALL RIBS
Have 3 articulations with the vertebral column
RIB 2 TO RIB 9
Articulates with the body of its own vertebra and with the body of the vertebra above
HEAD OF RIBS
Anteriorly, these articulates with the sternum
COSTAL CARTILAGE OF RIBS 1 TO 7
They articulate with the inferior margins of the costal cartilages above them
COSTAL CARTILAGES OF RIBS 8 TO 10
Known as the floating ribs because they do not articulate with other ribs, costal cartilages, or the sternum
RIB 11 AND RIB 12
True or False:
The costal cartilages of rib 11 and 12 are small, covering only their tips
TRUE
Provides extensive attachment site for muscles of the neck, abdomen, back, and upper limbs
SKELETAL FRAMEWORK OF THE THORACIC WALL
What surrounds the superior thoracic aperture
SKELETAL ELEMENTS
Consists of the body of vertebra T1, medial margin of rib 1, and the manubrium
SUPERIOR THORACIC APERTURE
The vertebra T1 is located where?
POSTERIORLY
The medial margin of rib 1 is located where?
EACH SIDE
The manubrium is located where?
ANTERIORLY
True or False:
the superior margin of the manubrium is in approximately the different horizontal plane as the intervertebral disc between vertebrae T2 and T3
FALSE, ITIS IN APPROXIMATELY THE SAME HORIZONTAL PLANE
The aperture that is large and expandable
INFERIOR THORACIC APERTURE
What are the structures that forms the margin of the Inferior thoracic aperture?
~BONE
~CARTILAGE
~LIGAMENTS
What closes the inferior thoracic aperture
DIAPHRAGM
TRUE OR FALSE:
The structures that passes between the abdomen and the thorax need to pierce or pass posteriorly to the diaphragm
TRUE
What are the skeletal elements of the inferior thoracic aperture?
~BODY OF VERTEBRA T12(POSTERIORLY)
~RIB 12 AND THE DISTAL END OF RIB 11(POSTEROLATERALLY)
~DISTAL CARTILAGINOUS ENDS OF RIBS 7 TO 10, WHICH UNITE TO FORM THE COSTAL MARGIN (ANTEROLATERALLY)
~XIPHOID PROCESS (ANTERIORLY)
TRUE OR FALSE:
The joint between the costal margin and the sternum lies roughly in a different plane as the intervertebral disc between vertebrae T9 and T10.
FALSE, IT LIES ROUGHLY IN THE SAME HORIZONTAL PLANE AS THE INTERVERTEBRAL DISC BEYWEEN VERTEBRAE T9 AND T10
TRUE OR FALSE:
The posterior margin of the inferior thoracic aperture is inferior to the anterior margin
TRUE
It seals the inferior thoracic aperture
DIAPHRAGM
How does the muscle fibers of the diaphragm arises? From the margins of the inferior thoracic aperture, and converge into a large central tendon.
RADIALLY
TRUE OR FALSE:
Because of the oblique angle of the inferior thoracic aperture, the posterior attachment of the diaphragm is superior to the anterior attachment
FALSE, THE POSTERIOR ATTACHMENT IS INFERIOR TO THE ANTERIOR ATTACHMENT
The diaphragm is not flat, it balloons posteriorly on both right and left sides forming what?
DOMES
TRUE OR FALSE:
The right dome is higher than the left dome, reaching as far as rib 5
TRUE
TRUE OR FALSE:
As the diaphragm contracts, the height of the domes decreases and the volume of the thorax increases
TRUE
Organs that penetrates the diaphragm
~ESOPHAGUS
~INFERIOR VENA CAVA
The structure that passes posteriorly to the diaphragm
AORTA
A thick midline partition that extends from the sternum anteriorly to the thoracic vertebrae posteriorly, and from the superior thoracic aperture to the inferior thoracic aperture.
MEDIASTINUM
A horizontal plane passing through the sternal angle and the intervertebral disc between vertebrae T4 and T5 separates the mediastinum into superior and inferior parts
TRUE
The inferior parts of mediastinum is further subdivided by what structure that also encloses the pericardial cavity surrounding the heart.
PERICARDIUM
What are the structures that constitute the middle mediastinum?
~PERICARDIUM
~HEART
The part of the mediastinum that lies between the sternum and the pericardium
ANTERIOR MEDIASTINUM
The part of the mediastinum that lies between the pericardium and thoracic vertebrae
POSTERIOR MEDIASTINUM
It is completely lined by a mesothelial membrane called the pleura, situated on either side of the mediastinum
PLEURAL CAVITIES
What covers the outer surface of each organ
PLEURA
The pleura lining the walls of the cavity
PARIETAL PLEURA
The pleura that covers the surfaces of the lungs
VISCERAL PLEURA
The lung does not completely fill the potential space of the pleural cavity which results to what?
It is also important for accommodating changes in lung volume during breathing
RECESSES
The largest and clinically most important recess that lies inferiorly between the thoracic wall and diaphragm
COSTODIA-PHRAGMATIC RECESS
What regions does the thorax have relationship with?
~NECK
~UPPER LIMB
~ABDOMEN
~BREAST
How is the neck related to the thorax?
THROUGH THE SUPERIOR THORACIC APERTURE THAT OPENS DIRECTLY INTO THE ROOT OF THE NECK
Until where does the superior part of the pleural cavity extends to when it has been fully developed?
APPROXIMATELY 2 TO 3 CM ABOVE RIB 1 AND THE COSTAL CARTILAGE INTO THE NECK.
In these pleural extensions, what structures pass between the neck and superior mediastinum
VISCERAL STRUCTURES
Where does the trachea lies immediately anterior to the esophagus?
IN THE MIDLINE
TRUE OR FALSE:
Major blood vessels and nerves pass in and out of the thorax at the inferior thoracic aperture anteriorly and laterally to these visceral structures
FALSE, IT PASSES AT THE SUPERIOR THORACIC APERTURE
What is the gateway to the upper limbs that lies on each side of the superior thoracic aperture?
AXILLARY INLET
How many axillary inlets are present in the superior thoracic aperture?
TWO
TRUE OR FALSE:
The two axillary inlets and the superior thoracic aperture communicates superiorly with the root of the neck.
TRUE
What forms the axillary inlet posteriorly?
SUPERIOR MARGIN OF THE SCAPULA
What forms the axillary inlet anteriorly?
CLAVICLE
What forms the axillary inlet medially
LATERAL MIDLINE OF RIB 1
How is the apex of each triangular inlet directed?
LATERALLY
What forms the apex of the triangular inlet and extends anteriorly from the superior margin of the scapula
MEDIAL MARGIN OF THE CORACOID PROCESS
What is the base of the axillary inlet’s triangular opening?
LATERAL MARGIN OF RIB 1
In what rib large blood vessels pass through in passing between the axillary inlet and superior thoracic aperture?
RIB 1
These parts also pass between the neck and upper limb by passing through the axillary inlet
PROXIMAL PARTS OF BRACHIAL PLEXUS
The structure that separates the thorax from the abdomen
DIAPHRAGM
TRUE OR FALSE:
Structures that pass between the thorax and abdomen either penetrate the diaphragm or pass posteriorly to it
TRUE
A structure or organ that pierces the central tendon of the diaphragm to enter the right side of the mediastinum near the vertebral level T8
INFERIOR VENA CAVA
A structure that penetrates the muscular part of the diaphragm to leave the mediastinum and enter the abdomen just to the left of the midline at a vertebral level T10
ESOPHAGUS
The structure that passes posteriorly to the diaphragm at the midline at vertebrae level T12
AORTA
TRUE OR FALSE:
Numerous other structures that pass between the thorax and abdomen pass through or anterior to the wall
FALSE, THEY PASS THROUGH OR POSTERIORLYTO THE DIAPHRAGM
What are the components of breasts?
~MAMMARY GLANDS
~SUPERFICIAL FASCIA
~OVERLYIBG SKIN
Where is the breast located?
ON THE PECTORAL REGION IN EACHSIDE OF THE ANTERIOR THORACIC WALL
What are the key features in the thorax?
~VERTEBRAL LEVEL T4/T5
~VENOUS SHUNTS FROM LEFT TO RIGHT
~SEGMENTAL NEUROVASCULAR SUPPLY OF THORACIC WALL
~SYMPATHETIC SYSTEM
~FLEXIBLE WALL AND INFERIOR THORACIC APERTURE
~INNERVATIONS OF THE DIAPHRAGM
These are used by physicians to determine the position of important anatomical structures within body regions
VERTEBRAL LEVELS
One of the most significant planes in the body
THE HORIZONTAL PLANE PASSING THROUGH THE DISC THAT SEPARATES THORACIC VERTEBRAE T4 AND T5
TRUE OR FALSE:
The horizontal plane passes through the sternal angle anteriorly, marking the position of the anterior articulation of the costal cartilage of rib 2 with the sternum
TRUE
This is used to find the position of rib 2 as a reference for counting ribs
STERNAL ANGLE
This causes the rib 1 to not be palpable
OVERLYING CLAVICLE
Is the rib 1 palpable or not palpable?
NOT PALPABLE
TRUE OR FALSE:
The horizontal plane separates the superior mediastinum from the inferior mediastinum and marks the position of the superior limit of the pericardium
TRUE
TRUE OR FALSE:
The horizontal plane marks where the arch of the aorta begins and ends
TRUE
TRUE OR FALSE:
The horizontal plane passes through the site where the superior vena cava
penetrates the pericardium to enter the heart
TRUE
TRUE OR FALSE:
The horizontal plane is the level at which the trachea bifurcates into right and
left main bronchi
TRUE
TRUE OR FALSE:
The horizontal plane marks the superior limit of the pulmonary trunk
TRUE
The chamber of the heart that receives deoxygenated blood from the body that lies on the right side of the midline and on the two major veins
RIGHT ATRIUM
What are the two major veins that drains into the right atrium?
SUPERIOR VENA CAVA
INFERIOR VENA CAVA
TRUE OR FALSE:
To get to the right side of the body, all blood coming from the left side has to cross the midline
TRUE
In adults, this crosses the midline immediately posterior to the manubrium and delivers blood from the left side of the head and neck, the left upper limb, and part of the left thoracic wall into the superior vena cava
LEFT BRACHIOCEPHALIC VEIN
These structures drain posterior and lateral parts of the left thoracic wall and passes immediately anterior to the bodies of the thoracic vertebrae, flowing into the azygos vein on the right side, that ultimately connects with the superior vena cava
HEMIAZYGOS AND ACCESSORY HEMIAZYGOS VEINS
Reflects the segmental organization of the wall
THE ARRANGEMENT OF VESSELS AND NERVES THAT SUPPLY THE THORACIC WALL
What are the sources of the arteries to the wall that arises
~THORACIC AORTA
~PAIR OF VESSELS(INTERNAL THORACIC ARTERIES)
Where is the thoracic aorta located
IN POSTERIOR MEDIASTINUM
Runs along the deep aspect of the anterior thoracic wall on either side of the sternum
INTERNAL THORACIC ARTERIES
Structures that branches segmentally from the internal thoracic arteries and pass laterally around the wall, mainly along the inferior margin of each rib
POSTERIOR AND ANTERIOR INTERCOSTAL VESSELS
Structure that runs with posterior and anterior intercostal vessels which innervates the wall, related parietal pleura, and associated skin
INTERCOSTAL NERVES
Reflects the segmental organization of the thoracic spinal nerves
DERMATOMES OF THORAX
Located mostly in the upper limb, not on the trunk.
It is an exception because it occurs anteriorly and superiorly
FIRST THORACIC DERMATOME
Receives branches from the anterior ramus of C4 via supraclavicular branches of the cervical plexus
ANTEROSUPERIOR REGION OF THE TRUNK
What is the highest thoracic dermatome on the anterior chest wall, which also extends into the upper limb
T2
It is located over the xiphoid process and is innervated by the T6
SKIN
Follows the contour of the ribs onto the anterior abdominal wall
DERMATOMES OF T7 TO T12
TRUE OR FALSE:
All preganglionic nerve fibers of the sympathetic system are carried out of the spinal nerves T1 to L2
TRUE
TRUE OR FALSE:
Sympathetic fibers found anywhere in the body ultimately emerge from the spinal cord as components of these spinal nerves
TRUE
Fibers carried out of the spinal cord in spinal nerve T1
PREGANGLIONIC SYMPATHETIC FIBERS DESTINED FOR THE HEAD
It is expandable because most ribs articulate with other components of the wall by true joints that allows movement, and because of the shape and orientation of the ribs
THORACIC WALL
TRUE OR FALSE:
A rib’s posterior attachment is superior to its anterior attachment.
TRUE
TRUE OR FALSE:
When a rib is elevated, it moves the anterior thoracic wall forward relative to the posterior wall, which is fixed
TRUE
TRUE OR FALSE:
the middle part of each rib is inferior to its two ends, so that when this region of the rib is elevated, it expands the thoracic wall laterally
TRUE
YES OR NO:
Is the diaphragm muscular or not?
MUSCULAR
It changes volume of the thorax in the vertical direction
DIAPHRAGM
Factors that are important for breathing
CHANGES IN THE ANTERIOR, LATERAL, AND VERTICAL DIMENSIONS OF THE THORACIC CAVITY
What innervates the diaphragm?
PHRENIC NERVES
Original form of phrenic nerves
BRANCHES OF THE CERVICAL PLEXUS IN THE NECK
Where does phrenic nerves arise from?
THE ANTERIOR RAMI OF CERVICAL NERVES C3, C4, AND C5,WITH MAJOR CONTRIBUTIONS COMING FROM C4
Passes vertically through the neck, the superior thoracic aperture, and mediastinum to supply motor innervation to the entire diaphragm, including the crura.
PHRENIC NERVES
Muscular extensions that attach the diaphragm to the upper lumbar vertebrae
CRURA
In the mediastinum, the phrenic nerves pass anteriorly to where?
TO THE ROOTS OF THE LUNGS
TRUE OR FALSE:
The tissue that gives rise to the diaphragm originates superiorly to the ultimate location ofthe diaphragm
TRUE
TRUE OR FALSE:
Spinal cords below the level of the origin of the phrenic nerves still affect the movement of the diaphragm
FALSE, IT DOES NOT AFFECT THE MOVEMENT OF THE DIAPHRAGM ANYMORE.