Thorax (Exam#2) Flashcards
Give the vertebral level of the jugular/suprasternal notch
Lower border of T2
Give the vertebral and costal levels of the sternal angle (of Louis)
Between T4-T5 posteriorly, and 2nd costal cartilage (CC) anteriorly.
Give the vertebral level of the xiphisternal joint
T9
Give the costal levels of the costal margin (lower border of chest/thorax)
7th-10th costal cartilages
Give the intercostal space (ICS) level and vertebral level of the nipple
4th ICS, T4-T5
Give the costal level of the apex of the heart
Left 5th ICS, 1/2 inch medial to the midclavicular line.
The transverse thoracic plane lies between which two vertebral levels?
T4-T5
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Which rib(s) attach ENTIRELY to the manubrium?
1st rib only; the 2nd rib attaches at the sternal angle and, thus, attaches to both the manubrium and the body of the sternum.
At which joint is the angle of Louis formed?
Manubriosternal joint
At which vertebral levels is the body of the sternum located?
T5-T9
p.78 Moore
At what vertebral level is the xiphoid process located?
Its inferior end lies at T10
What three thoracic viscera can the xiphoid process be a midline marker for, i.e. what three organs can be found at the midline using the xiphoid process as a landmark?
- Xiphoid process ≈ T10 vertebral level*
1. ) Superior limit of the liver
2. ) Central tendon of the diaphragm
3. ) Inferior border of the heart
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What bony landmark indicates the inferior limit of the central part of the thoracic cavity projected onto the anterior body wall?
Xiphisternal joint: Junction between the body of the sternum and the xiphoid process.
- ) What bony landmark can be used to locate the infrasternal angle (aka _______ angle)?
- ) What forms the infrasternal angle?
- ) aka Subcostal angle –Xiphisternal joint.
2. ) Formed by the apex of the right and left costal margins.
Give the borders of the thoracic cage (superior, inferior, lateral, anterior, posterior).
Superior: Thoracic inlet and suprapleural membrane. Inferior: *Thoracic diaphragm* Lateral: 12 ribs and their cartilage. Anterior: Sternum. Posterior: 12 thoracic vertebrae.
What are the borders of the superior thoracic aperture (anterior, posterior, lateral)?
Anterior: Superior border of manubrium
Posterior: T1
Laterally: 1st pair of ribs and their cartilage.
What structures pass through the superior thoracic aperture (10)?
- Trachea
- Esophagus
- Phrenic nerves
- brachial plexus (lower trunk)
- internal thoracic artery
- brachiocephalic artery
- subclavian artery and vein
- thoracic duct,
- Anterior scalenes
- T1 and C8 anterior rami
What are the borders of the inferior thoracic aperture (anterior, anterolateral, posterior, posterolateral)?
- Anterior: Xiphisternal joint.
- Anterolateral: Joined costal cartilages of ribs 7-10 (costal margins).
- Posterior: T12.
- Posterolateral: 11th and 12th pair of ribs.
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The domes of the diaphragm rise to the level of which intercostal space?
4th ICS
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Describe the articulation between the head of the ribs and the costal facets of the thoracic vertebrae, give an example.
The head of the rib articulates with the superior costal facet of the corresponding (same numbered) vertebrae (i.e. inferior articular facet of the head of the rib articulates with the superior costal facet of the vertebrae at the same level).
The superior articular facet of the head of the rib articulates with the inferior articular facet of the vertebrae superior to it (i.e. one number lower).
e.g. The head of the 6th rib articulates with the superior costal facet of T6, and the inferior costal facet of T5.
Describe the articulation between the tubercle of the ribs and the thoracic vertebrae, give an example.
The tubercle of the ribs articulate with the transverse costal facet of the corresponding (same numbered) vertebrae.
e.g. The tubercle of the 6th rib articulates with the transverse costal facet of T6.
Describe the relative length of the ribs in order of increasing number.
Length increases from 1 to 7, then decreases.
Explain the borders of the superior mediastinum.
The superior mediastinum extends inferiorly from the superior thoracic aperture to the horizontal plane that includes the sternal angle anteriorly and passes approximately through the junction (IV disc) of T4 and T5 vertebrae posteriorly, often referred to as the transverse thoracic plane.
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What are the contents of the middle mediastinum (5)?
The middle mediastinum includes the
1.) pericardium, heart, and the roots of its great vessels (Fig. 1.34)—
2.) ascending aorta,
3.) pulmonary trunk
4.) SVC (PVs)—passing to and from the heart –
5.) Phrenic nerve
Moore p.128
The fibrous pericardium is continuous with what tendinous structure?
The central tendon of the diaphragm (Fig. 1.32).
What are the contents of the superior mediastinum from anterior to posterior (6)?
Contents of Superior Mediastinum (anterior to posterior)
1.) Thymus
2.) Veins: Brachiocephalic veins and
SVC – ANTERIOR TO THE ARTERIES.
3.) Arteries: Arch of aorta and roots of its major branches—the brachiocephalic trunk, left common carotid artery, and left subclavian artery – and related nerves (vagus and phrenic nerves and the cardiac plexus of nerves).
4.) Trachea anteriorly
5.) Esophagus posteriorly) and related nerves (left recurrent laryngeal nerve).
6.) Thoracic duct and lymphatic trunks.
Summarize systemically, the order of the major structures in the superior mediastinum, from anterior to posterior (6)
MNEMONIC
(1) thymus, (2) veins, (3) arteries, (4) airway, (5) alimentary tract, and (6) lymphatic trunks.
MNEMONIC: Tight Vag’s ARe Actually ALways Loose
Give the boundaries of the anterior mediastinum: Front, lateral, posterior, anterior.
- Front by the sternum.
- Laterally by the pleurae.
- Posteriorly by the pericardium.
- Anteriorly by the left Transversus thoracis and the fifth, sixth, and seventh left costal cartilages.
Give the contents (5) of the anterior mediastinum
- A quantity of loose areolar tissue.
- Some lymphatic vessels which ascend from the convex surface of the liver.
- Two or three anterior mediastinal lymph nodes.
- The small mediastinal branches of the internal mammary artery.
- Thymus (involuted in adults).
Concerning the posterior mediastinum, list all of the structures that it lies immediately above, below, anterior, posterior, and between.
Located inferior to the transverse thoracic plane.
• Anterior to the T5-T12 vertebrae.
• Posterior to the pericardium and diaphragm.
• Between the parietal pleura of the two lungs.
• Above the thoracic surface of the diaphragm.
What are the contents of the posterior mediastinum? MNEMONIC
*DATES* Descending aorta Azygos vein and hemiazygos vein Thoracic duct Esophagus Splanchnics
What does the thoracic duct drain?
All lymph except that from the right superior quadrant.
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The ______ of the thorax increases considerably when the intercostal muscles contract.
AP dimension
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- ) The pump-handle movement increases the _____ dimension of the thoracic cage.
- ) The bucket-handle movement increases the _____ dimension of the thoracic cage.
- ) Combined, these movements cause the thoracic cage to move in which directions?
- ) AP dimension
- ) Transverse dimension
- ) Anteriorly, superiorly, and laterally.
Which ribs articulate with the body of the sternum?
2-7
What two structures are located posterior to the manubrium?
- ) Arch of aorta (and its branches)
- ) Left brachiocephalic vein
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What seven anatomical features are associated with the sternal angle?
- ) T4-T5 disc
- ) 2nd rib articulation
- ) Ascending aorta ends***
- ) Descending aorta begins***
- ) Arch of aorta ends and begins
- ) Trachea bifurcates***
- ) Azygous vein joins SVC**
* Highest point of arch of aorta IS NOT at this point!
Give the vertebral levels of the following openings in the diaphragm and what travels with the structures:
- ) Vena cava (2)
- ) Esophageal (3)
- ) Aortic (3)
1.) T8: Inferior vena cava, branches of R phrenic nerve.
2.) T10: Esophagus, vagus nerve, esophageal branch of left gastric artery.
3.) T12: Aorta, thoracic duct, Azygos vein.
Mnemonic: “8-10-12” CEA: Caval, esophageal, aortic.
Give the innervation (and nerve roots) of the diaphragm (2 – central and peripheral)
- ) Phrenic nerve (C3, 4, 5): Motor to entire muscle, sensory to the CENTRAL part.
- ) Lower Five Intercostals and Subcostals: Sensory to the PERIPHERAL part.
What crosses the internal thoracic arteries near their origins?
ipsilateral phrenic nerves
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Where and into what (what do they divide into) do the internal thoracic arteries terminate?
Terminate in the 6th intercostal spaces and divide into the superior epigastric (medially) and musculophrenic (laterally) arteries.
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The 7th – 9th anterior intercostal arteries derive from the ____________.
musculophrenic artery
The anterior intercostal arteries are absent from the _________, which are supplied by the posterior intercostals and their collateral branches.
inferior two ICSs
Posterior intercostals veins ____–______ end in the azygos/hemi-azygos venous system, which conveys blood to the _______.
5–11
- superior vena cava
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The _______________ is typically the final tributary of the azygos vein, before it enters the SVC.
right superior intercostal vein
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The _______ and _______ veins drain directly into the brachiocephalic veins.
right and left 1st posterior intercostal veins
Give the arterial supply for the breast (4)
Internal thoracic
Lateral thoracic
Thoracoacromial
Posterior intercostal arteries
Give the venous supply for the breast (3)
- ) Axillary vein (mainly)
- ) Internal thoracic (some)
- ) Posterior intercostal vein
* Communicates with the vertebral venous plexus*
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Most lymph (>75%), especially from the ______ breast quadrants, drains into the ______ lymph nodes, initially to the ______ or ______ lymph nodes.
- lateral
- axillary lymph nodes, initially to the anterior or pectoral lymph nodes.
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Lymph from the medial breast quadrants mainly drains to the ______ lymph nodes or to ________.
parasternal lymph nodes or to the opposite breast
Lymph from the inferior quadrants may pass deeply to _______ lymph nodes (_________ lymph nodes).
abdominal lymph nodes (subdiaphragmatic inferior phrenic lymph nodes).
Lymph from the skin of the breast, except the nipple and areola, drains into the ________, ________, and ________ lymph nodes and into the ________ lymph nodes of both sides.
ipsilateral axillary, inferior deep cervical, and infraclavicular lymph nodes and into the parasternal lymph nodes of both sides.
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What supplies innervation to the breasts?
Anterior and lateral cutaneous branches of the 4th–6th intercostal nerves.
Lymph from the parasternal nodes enters the _________ lymphatic trunks, which also drain lymph from the ________.
- Bronchomediastinal
- Thoracic viscera
Lymph from the axillary nodes drains into__________ lymph nodes and from them into the ________ lymphatic trunk.
- clavicular (infraclavicular and supraclavicular)
- subclavian lymph trunk
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The ____________ appearance of of breast skin is due to the infiltration of superficial lymphatic vessels.
Peau d'orange #91
Retraction of the nipple is due to ___________ and consequent fibrosis.
due to infiltration of the lactiferous ducts. #91
Breast fixity is due to ______________. Contraction here can cause _________ or _________.
-infiltration of the suspensory ligament
-retraction or puckering of the skin.
#91
The mammary gland is supplied from its medial aspect mainly by perforating branches of the ________ artery and by several branches of the _______ artery (principally the ________ artery) superiorly and laterally.
- internal thoracic artery
- axillary artery
- (principally the lateral thoracic artery) superiorly and laterally.
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How can cancer spread from the breast to the brain?
The posterior intercostal veins drain into the azygos/ hemi-azygos system of veins alongside the bodies of the ver- tebrae (see Fig. 1.38B) and communicate with the internal vertebral venous plexus surrounding the spinal cord.
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How many external intercostal muscles are there on each side of the thorax?
11
What is the origin and insertion of the transversus thoracis?
Origin: Posterior surface of lower border of sternum and xiphoid process.
Insertion: Inner surfaces of costal cartilages 2-6.
What is the clinical significance of the endothoracic fascia?
It forms a natural cleavage plane for surgical separation of costal pleura from the thoracic wall.
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At the hilum of the lung, it is the _______ pleura that reflects laterally onto the root of the lung to become continuous with the visceral pleura.
mediastinal
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The horizontal fissure of the right lung parallels the _____ rib.
4th rib
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What is the extent of the costodiaphragmatic recess?
Extends from the 8th-10th ribs along the midaxillary line.
Why is the left costodiaphragmatic recess larger than the right?
The left recess is larger (less occupied) because the cardiac notch in the left lung is more pronounced than the corresponding notch in the pleural sac.
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The inferior borders of the lungs move farther into the pleural recesses during _______ and retreat from them during _______.
farther into the pleural recesses during deep inspiration and retreat from them during expiration.
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The thoracic aorta begins on the left side of the inferior border of the body of the ____ vertebra and descends in the ________ mediastinum on the left sides of the ______-______ vertebrae.
- body of the T4 vertebra
- posterior mediastinum
- left sides of the T5–T12 vertebrae
Describe the course of the descending aorta in the thorax
Descends in posterior mediastinum to left of vertebral column; gradually shifts to right to lie in median plane at aortic hiatus.
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Give the posterior (SP) and anterior (CC) borders of the oblique lung fissure
From SP of T3 posteriorly to 6th CC anteriorly
Bronchioles lack _______ in their walls. Conducting bronchioles transport air but lack ______ or _______.
- lack cartilage in their walls
- glands or alveoli
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The right and left pulmonary arteries arise from the ________ at the level of the _______; they carry _______ blood to the lungs for oxygenation.
- pulmonary trunk at the level of the sternal angle
- low-oxygen (“venous”)
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Describe:
- ) The nature of a pulmonary embolism
- ) Where they usually arise
- ) Clinical presentation
- ) Obstruction of pulmonary artery or its branches by an embolus.
- ) Usually arise in deep veins of lower limb.
- ) Symptoms are sudden onset of dyspnea, chest pain.
- ) Describe the what results from a malignant neoplasm of lung apex.
- ) Symptoms (pain, location?)
- ) Secondary syndromes?
- ) Compresses lower trunk of brachial plexus.
- ) Causes severe pain radiating towards shoulder and medial aspect of arm, atrophy of muscles of forearm and hand)
- ) Compression of sympathetic chain ganglia resulting in Horner’s syndrome (ipsilateral miosis, ptosis and anhydrosis).
- ) Aspirated foreign objects tend to enter the _______
2. ) In erect position, tends to lodge in the ______ segment of the ______ lobe on the _____ side.
- ) right bronchus
2. ) posterior basal segment of the lower lobe on the right side.
- ) In supine position, aspirated objects tends to lodge in the _______ segment of the ______ lobe or ______ segment of the _______ lobe on the ______ side.
- ) What type of treatment would this require?
- ) Apical / superior segment of the lower lobe or posterior segment of the upper lobe on the right side.
- ) Segmental resection - removal of a segment without damaging neighbor segment.
- ) The bronchi receive parasympathetic innervation from the ______ nerve.
- ) Motor to bronchial muscle and on stimulation cause _______.
- ) Secretomotor to the _______
- ) Sensory for ______ and _______.
- ) vagus nerve.
- ) bronchospasm
- ) mucous glands
- ) stretch and cough reflex
- ) Sympathetic innervation to the bronchi arises from the ______ spinal segments
- ) Stimulation causes _______
- ) Form anterior and posterior ________ located anterior and posterior to ______, respectively
- ) T2-5
- ) bronchodilation
- ) pulmonary plexuses, roots
Two pulmonary veins, a ________ and ______ pulmonary vein on each side, carry _______ blood from corresponding lobes of each lung to the _______ of the heart.
- superior and an inferior pulmonary vein on each side
- oxygen-rich (“arterial”)
- left atrium
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- ) ________ supply blood for nutrition of the structures making up the root of the lungs, the supporting tissue of the lungs, and the visceral pleura.
- ) How many are there on each side?
- ) Where do they arise form ?
- ) Bronchial arteries.
- ) One on the right, two on the left.
- ) Both arise from the descending thoracic aorta.
p. 117 Moore.
Where do the two pairs of right and left bronchial veins drain?
Right: Azygos.
Left: Superior intercostal or accesory hemiazygos.
What supplies lymphatic drainage to the lungs?
Bronchopulmonary lymph nodes.
The cell bodies for the sympathetic fibers of the pulmonary plexus are in the _________. The sympathetic fibers are ________ to the bronchial muscle.
- Paravertebral sympathetic ganglion of the sympathetic trunks.
- The sympathetic fibers are inhibitory to bronchial muscle (bronchodilator).
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The horizontal fissure of the right lung extends from the oblique fissure along the ______ rib and costal cartilage anteriorly.
4th rib
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The fibrous pericardium is attached to the ________ of the diaphragm by the ______.
Central tendon of the diaphragm by the PERICARDIOPHRENIC LIGAMENT.
The ________ protects the heart against sudden overfilling because it is so unyielding and closely related to the great vessels that pierce it superiorly.
fibrous pericardium
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The _______ carries the pericardium superiorly beyond the heart to the level of the _______.
- ascending aorta
- sternal angle
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The ________ pericardium forms the epicardium, the outermost of three layers of the heart wall.
- visceral layer of serous pericardium
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At what points is the visceral pericardium continuous with the parietal layer of serous pericardium (2)?
- ) Where the aorta and pulmonary trunk leave the heart.
- ) Where the SVC, IVC, and pulmonary veins enter the heart.
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What is the transverse pericardial sinus?
A transversely running passage within the pericardial cavity between the aorta and pulmonary artery in front, and the SVC behind, and the reflection of serous pericardium around them.
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What is the oblique pericardial sinus? What is it bound by?
A wide recess in the posterior wall of the pericardial sac –Bounded laterally by the entrances of the pulmonary veins and inferiorly by the orifice of the IVC.
What is the arterial supply for the pericardium? From which artery does it arise?
Pericardiophrenic artery –Branch of the internal thoracic artery; often accompanies or at least parallels the phrenic nerve to the diaphragm.
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- ) What supplies sensory fibers to the pericardium? Where is pain referred to?
- ) What else supplies innervation?
- ) Phrenic nerve (C3-C5): 1˚ source of sensory fibers; pain commonly referred to skin (C3-C5 dermatomes) of the ipsilateral supraclavicular region (i.e. top of shoulder on the same side).
- ) Sympathetic trunks –Vasomotor.
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What chamber(s) forms the base of the heart?
Formed mainly by the left atrium, with a lesser contribution from the right atrium.
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What chamber(s) forms the apex of the heart?
Formed by the inferolateral part of the left ventricle.
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What vertebrae does the base of the heart face? What separates it from them?
Faces posteriorly toward the bodies of vertebrae T6–T9 and is separated from them by the pericardium, oblique pericardial sinus, esophagus, and aorta.
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Which surface of the heart forms the cardiac impression on the left lung?
Left pulmonary surface
List the four surfaces of the heart and which chamber(s) makes forms them.
- Anterior (sternocostal) surface: Formed mainly by right ventricle.
- Diaphragmatic surface: Formed mainly by the left ventricle, partly by the right.
- Related mainly to the central tendon of the diaphragm. - Right pulmonary surface: Formed mainly by the right atrium.
- Left pulmonary surface: Formed mainly by the left ventricle; forms the cardiac impression in the left lung.
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List the four borders of the heart and what they encompass
- Right border (slightly convex), formed by the right atrium and extending between the SVC and the IVC.
- Inferior border (nearly horizontal), formed mainly by the right ventricle and slightly by the left ventricle.
- Left border (oblique, nearly vertical), formed mainly by the left ventricle and slightly by the left auricle.
- Superior border, formed by the right and left atria and auricles in an anterior view; the ascending aorta and pulmonary trunk emerge from this border and the SVC enters its right side. Posterior to the aorta and pulmonary trunk and anterior to the SVC, this border forms the inferior boundary of the transverse pericardial sinus.
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The _______ is the arterial continuation of the right ventricle.
Pulmonary trunk
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What is the sulcus terminales?
Shallow vertical groove that externally separates the smooth and rough parts of atrial wall.
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The SVC opens into the superior part of the right atrium at the level of the _______ costal cartilage. IVC?
- right 3rd costal cartilage
- IVC: 5th CC.
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The ______ papillary muscle is the largest of the three papillary muscles and is attached to the _____ border of the ______ wall.
- anterior papillary muscle.
- inferior border of the anterior wall.
At what external landmark and ICS is the AV (tricuspid) orifice found?
located posterior to the body of the sternum at the level of the 4th and 5th intercostal spaces.
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What keeps the right AV (tricuspid) orifice caliber constant (large enough to admit the tips of three fingers), resisting the dilation that might otherwise result from blood being forced through it at varying pressures?
Fibrous skeleton of the heart
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The pulmonary valve at the apex of the _______ is at the level of the ______ costal cartilage.
- conus arteriosus
- left 3rd CC
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Where are pectinate muscle found?
Majority of the right atrial wall, and only in the auricle of the left atrium.
The ascending aorta begins at the _______.
aortic orifice.
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The mitral valve is located posterior to the ______ at the level of the ____ costal cartilage.
posterior to the sternum at the level of the 4th costal cartilage.
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The aortic valve is located posterior to the ___________ at the level of the ____ intercostal space.
posterior to the left side of the sternum at the level of the 3rd intercostal space.
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Where is the tricuspid valve best heard?
4th left intercostal space –Over inferior middle sternum.
Where is the bicuspid valve (mitral) best heard?
Over apex of heart (5th L ICS at midclavicular line)
Where is the pulmonary valve best heard?
Second right ICS, just lateral to the sternum.
Where is the aortic valve best heard?
Second left ICS, just lateral to the sternum.
Dominance of the coronary arterial system is defined by which artery gives rise to the __________ branch (__________ artery). Which type of dominance is typical?
posterior interventricular (IV) branch (posterior descending artery). Right dominance is typical. p.145 Moore
Typically, the RCA supplies… (6)
- The right atrium.
- Most of right ventricle.
- Part of the left ventricle (the diaphragmatic surface).
- Part of the IV septum, usually the posterior third.
- The SA node (in approximately 60% of people).
- The AV node (in approximately 80% of people).
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Typically, the LCA supplies…(5)
- The left atrium.
- Most of the left ventricle.
- Part of the right ventricle.
- Most of the IVS (usually its anterior two thirds), including the AV bundle of the conducting system of the heart, through its perforating IV septal branches.
- The SA node (in approximately 40% of people).
The coronary sinus receives the ________ at its left end, and the _______ and _______ at it right end.
great cardiac vein at its left end, and the middle cardiac vein and small cardiac veins at it right end.
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- ) Regarding SVC, it passes inferiorly and ends at the level of the _____ costal cartilage, where it enters the right atrium of the heart.
- ) The SVC lies in the right side of the superior mediastinum, _______ to the trachea and ________ to the ascending aorta.
- ) The _________ lies between the SVC and the mediastinal pleura.
- ) The terminal half of the SVC is in the middle mediastinum, where it lies beside the ______ and forms the posterior boundary of the _______ (Fig. 1.46).
- ) 3rd costal cartilage
- ) Right side of the superior mediastinum, anterolateral to the trachea and posterolateral to the ascending aorta.
- ) right phrenic nerve
- ) ascending aorta, transverse pericardial sinus
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At the level of the _____ border of the _____ right/left? costal cartilage, the brachiocephalic veins unite to form the SVC
inferior border of the 1st right costal cartilage
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The right recurrent laryngeal nerve hooks around the __________ artery and ascends between the _____ and ______ to supply the ______.
- right subclavian artery
- ascends between the trachea and esophagus to supply the larynx.
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The right vagus nerve runs posteroinferiorly through the superior mediastinum on the _____ side of the trachea. It then passes ______ to the right brachiocephalic vein, SVC, and root of the right lung.
- on the right side of the trachea
- posterior to the right brachiocephalic vein, SVC, and root of the right lung.
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The great cardiac vein drains the areas of the heart supplied by _______.
the LCA.
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Which two veins generally drain the areas supplied by RCA?
Small cardiac and middle cardiac
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- ) What spinal cord segments does the SNS innervation to the cardiac plexus come from?
- ) Where are the cell bodies for the postsynaptic sympathetic fibers?
- ) T1–T5/6.
- ) Cervical and superior thoracic paravertebral ganglia of the sympathetic trunks.
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What is the affect of SNS stimulation on the heart?
Sympathetic stimulation causes increased heart rate, impulse conduction, force of contraction, and, at the same time, increased blood flow through the coronary vessels to support the increased activity
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What is the affect of SNS stimulation on the coronary vessels?
Inhibition – i.e. dilation.
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Where do PSNS presynaptic fibers to the heart come from? Where are the postsynaptic cell bodies? (2)
The parasympathetic supply is from presynaptic fibers of the vagus nerves. Postsynaptic parasympathetic cell bodies (intrinsic ganglia) are located in the atrial wall and interatrial septum near the SA and AV nodes and along the coronary arteries.
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