Thorax Flashcards
How many ribs are there and what are their classifications?
1-7: True ribs, articulate with sternum (synovial)
8-10: False ribs, attach with superior costal cartilage
11-12: floating ribs, terminate in abdominal muscles, do not articulate
What are the different parts of the rib?
Head: 2 facets, for articulation with superior or inferior vertebral demifacets. costovertebral joints
Neck: for attachment for radiate ligament
Tubercle: facet; for articulation to transverse process
costotransverse joint- synovial joint which uses costotransverse ligament
Angle: most posterior part, most likely fracture point, contains primary bony center
Body: subcostal groove, contains NV bundle, articulates with either sternum, cartilage, or terminates in abdominal muscles
What are the joints involved with each rib?
costovertebral - synovial
costotransverse - synovial
costochondral - primary cartilaginous
What are the ligaments involved with each rib?
radiate (costovertebral)
superior / lateral costovertebral (costotransverse)
What are the muscles involved with the ribs?
External intercostal
Internal intercostal
Innermost intercostal
NV bundle runs in between the internal intercostal + innermost intercostal [Nerve, Artery - intercostal A off aorta, intercostal V]
What is the ossification / fusion of the rib?
Bony center - in the angle
during the 8th week of life
Secondary centers in tubercle, and head at 15 weeks, fuse at 25 weeks
What are the anatomical variants associated with the ribs?
Cervical rib
Lumbar rib
Bifid rib
Only 11 rib pairs
hypoplastic rib
Fused rib
1st rib - fibrous band, 1st rib pseudoarthirtis
What is the function of the first rib?
Anatomical landmark
Most superior rib
What are the specifics parts of the first rib?
Head - only has one facet, articulates with T1
Neck - crossed by the sympathetic trunk
Tubercle - present to articulate with facet of transverse process
Scalene Tubercle - exists for the attachment of scalene anterior
Body - has a groove for subclavian artery + subclavian vein
groove for the subclavian vein is anterior to the scalene tubercle
groove for the subclavian artery is posterior to the scalene tubercle, also inferior to the trunks of the brachial plexus
What are the joints involved in the first rib?
Costotransverse - synovial
Costochondral - primary cartilaginous
Costovertebral - synovial
What are the relations of the first rib?
SUPERIOR: clavicle, subclavian artery, subclavian vein, anterior scalene, brachial plexus
INFERIOR: parietal pleura, intercostal artery, nerve, vein
ANTERIOR: sympathetic trunk, superior/supreme intercostal artery (coming off costocervical trunk)
POSTERIOR: internal thoracic artery + vein (behind the costochondral joint)
What are the ligaments involved with the first rib?
Radiate
costoclavicular ligament
superior - lateral costotransverse ligament
What are the muscles involved with the first rib?
anterior scalene
Middle scalene
Subclavius
External / internal / innermost intercostal
What are the anatomical variants associated with the first rib?
bifid rib
Forked rib
fibrous articulation / fusion with cervical rib
Rudimentary / hypoplastic rib
pseudoarthrosis of first rib
What are the parts of the sternum?
Menubrium, body, xiphoid process
What does the menubrium articulate with?
Articulates with the ribs 1,2
clavicle
the body of the sternum inferiorly at the sternal angle
What does the body of the sternum articulate with?
Articulates with ribs 3-7
Articulates with the manubrium superiorly, xiphoid inferiorly
What are the joints involved with the sternum?
manubrio-sternal angle -
at level T4-T5
What are the ligaments involved with the sternum?
Radiate ligaments (involved in the costochondral joints)
What are the relations to the sternum?
Posterior: pericardial sac
internal thoracic artery + vein
Superior: superior thoracic outlet, clavicle + interclavicular ligament
Inferior: superior epigastric arteries
Lateral: ribs 1-2 attach to menubrium, 3-7 attach to body
What is the ossification timeline for the sternum?
4 primary centres - sternbrae appear in the 5th to 9th fetal month
xiphoid process fuses with body at 40 (if at all)
What are the anatomical variants associated with the sternum?
Pectus carinatum - prominence of midportion
Pectus excavatum - depression of lower end
sternal foramen - most common in inferior aspect of body
What is scalene anterior?
It is a key anatomical landmark for the superior thoracic aperture
Divides the subclavian artery into 3, and brachial plexus runs behind it
Where does scalene anterior sit?
Sits in the superior thoracic aperture - covered in prevertebral fascia
What is the gross anatomy of scalene anterior?
origin: transverse processes of C3-C6
insertion: scalene tubercle of 1st rib
What is the action of the scalene anterior?
raise first rib in inspiration
What is the nerve supply for scalene anterior?
C3, C4, C5
What are the relations of the scalene anterior?
Subclavian artery is posterior
Subclavian vein is anterior
Trunks of brachial plexus are behind the scalene anterior
Divides up the subclavian A into 3rds
Vagus + phrenic N descend over scalene Ant however vagus is in carotid sheath
What is immediately anterior to scalene anterior?
subclavian vein
internal jugular vein
Internal carotid A
External carotid A
Branches of thyrocervical trunk (suprascapular, ascending cervical, transverse cervical)
phrenic N
vagus N
What is immediately posterior to scalene anterior?
Artery - second part of subclavian artery
nerve - trunks of the brachial plexus
What is immediately medial to scalene anterior?
Artery- first part of subclavian, common carotid artery, vertebral artery
vein - internal jugular vein
nerve - recurrent laryngeal N in tracheoeophageal groove
Thoracic duct (on left), right lymphatic duct (on right)
trachea, thyroid
What is lateral to scalene anterior?
artery - 3rd part of subclavian (posterolateral)
subclavian vein
brachial plexus
internal jugular vein
recurrent laryngeal N
What is the superior thoracic aperture?
Superior thoracic aperture connects the root of the neck to the superior mediastinum
Lies in an oblique plane, tilted anteriorly
What is the gross anatomy of the superior thoracic aperture?
anterior:
menubrium of the sternum
posterior:
t1 vertbra
lateral:
first rib
What are the contents of the superior thoracic aperture?
Viscera
thymus
lung apices
trachea
oesophagus
Arteries
subclavian A
common carotid A
Veins
subclavian V
internal jugular V
Nerves
brachial plexus
phrenic N
vagus N
recurrent laryngeal N
lymphatics
thoracic duct
R lymphatic duct
muscles
sternocleidomastoid
anterior scalene
infrahyoid strap muscles - sternohyoid, sternothyroid
ligaments / fascia
prevertebral fascia
What is the function of the trachea?
mucocilliary escalator to remove particulate
To allow air exchange
Where does the trachea sit?
Sits in the lower border of the cricoid cartilage - C6
To the carina - T4/T5
Terminates at the carina to divide into the bronchial tree
In the posterior mediastinum
What is the trachea made up of?
D shaped cartilage rings
Rings are joined by muscle called trachealis muscle
Each ring is joined by the annular ligaments
lined with ciliated columnar epithelium
divided into cervical trachea and thoracic trachea
What are the relations of the cervical trachea?
Anterior: thyroid isthmus, inferior thyroid vein, infrahyoid strap muscles
Posterior: oesophagus, tracheooesophageal groove (with RLN)
Lateral: lobes of thyroid, carotid sheath (CCA, IJV, vagus N), RLN in groove
What are the relations of the thoracic trachea?
Anterior: ascending arch of aorta, pulmonary trunk, L CCA + L brachiocephalic vein
Posterior: oesphagus, vagus
Lateral: on left will be arch of aorta, left CCA, subclavian and vagus
on right will be arch of azygos, vagus N, pleura
What is the arterial supply of the trachea?
Cervical - inferior thyroid A
Thoracic - bronchial A
What is the venous drainage of the trachea?
Cervical - inferior thyroid vein plexus
Thoracic - inferior thyroid vein plexus + azygos vein
What is the lymphatic drainage of the trachea?
cervical = level 6 + 7 stations in neck
thoracic = level 1 - 8 stations in the mediastinum
What are the muscles and ligaments involved with the trachea?
Trachealis
Annular ligaments
What is the anatomical variants associated with the trachea?
oesophageal bronchus
supracarinal bronchus
pig bronchus (supracarinal bronchus which supplies an entire lobe)
lunate trachea
tracheal diverticulum
oesophageal atresia - TOF
What is the function of the phrenic nerve?
sensory + motor supply to the diagphram
What is the origin of the phrenic n?
C3,C4,C5 nerve roots
What is the course of the phrenic N?
descends on anterior scalene
left - arterial relations
right - venous relations
Through the pericardial course, will run with the pericardiophrenic artery + vein
What are the relations of the left phrenic N?
Anterior to the subclavian A
Lateral to the arch of aorta
Lateral to the left auricle
Anterior to lung hilum
Lateral to left ventricle
Pierces dome of left diagphram
What are the relations of the right phrenic N?
Posterior to subclavian V
Lateral to superior vena cava
Lateral to right atrium
Anterior to lung hilum
Lateral to right ventricle
Passes through vena caval foramen (T8)
Where does the phrenic N terminate?
LEFT phrenic N:
Pierces through the hemidiagphram independently
RIGHT phrenic N:
travels through the vena caval foramen at T8
What does the phrenic N supply?
Motor and sensory supply of the diagphram
Mediastinal pleura
pericardium
What is the bronchial tree?
Tubes which permit air transmission between trachea and subsegmental bronchi
What is the function of the bronchial tree?
Function is to permit air transmission to bronchioles
Mucocillary escalator removes particulates
Where does the bronchial tree sit?
Inferior to the carina at T4-T5
What is the general anatomy of the lung with respect to bronchial tree?
Right lung - 3 lobes, 10 segments
Left lung - 2 lobes, 8 segments
What are main differences between bronchi?
Right main bronchi - shorter, fatter, more vertical (posterior surface is in contact with the lung)
Left main bronchi - longer, more horizontal
What do each of the Right bronchi supply?
Right upper lobe
Apical lobe
Anterior lobe
Posterior lobe
Right middle lobe - intermediate bronchus
Medial lobe
Lateral lobe
Right lower lobe - intermediate bronchus
Apical basal
Anterior basal
Lateral basal
Posterior basal
Medial basal
What do each of the left main bronchi supply?
Left upper lobe bronchus
apicoposterior
anterior
superior lingula
inferior lingula
Left lower lobe bronchus
apical
anterior
lateral
posterior
What are the relations of the right main bronchus?
Superior - arch of azygos vein
Anterior - right pulmonary artery, right pulmonary vein, phrenic N, vena cava
Posterior - azygos vein
What are the relations of the left main bronchus?
Longer, narrower, more horizontal
Posterior surface is in contact with lung
Superior: ARCH of aorta
Anterior: pulmonary trunk, left pulmonary artery, left pulmonary vein, left phrenic nerve
Posterior: oesophagus, descending aorta
What is the arterial supply of the bronchi?
Bronchial arteries - coming off aorta
What is the venous drainage of the bronchi?
bronchial veins - drainage to SVC, pulmonary veins, azygos
What is the lymphatic drainage of the bronchi?
Drain to the supracarinal nodes - level 8-9-10
What are the anatomical variations of the bronchi?
oesophgeal bronchus
supracarinal bronchus
pig bronchus
cardiac bronchus
azygos bronchus
Extra fissures -very common - and can have a bronchus to supply it
What is the left subclavian artery?
It is the artery which supplies blood to the cerebral circulation (via cerebral artery)
posterior neck (via costocervical trunk)
chest (via internal thoracic artery)
and upper limb
Where does the subclavian artery sit?
in the root of neck
intimately related to anterior scalene
What is the gross anatomy of the subclavian artery?
It is split into 3 parts - relative to scalene anterior.
1st part - in superior thoracic aperture, from origin to medial border of anterior scalene
2nd part - posterior to anterior scalene
3rd part - lateral border anterior scalene to lateral border first rib
What is the course of the subclavian artery?
Comes off the arch of aorta. infront of trachea at T4-T5
Travels then posterior to anterior. scalene
To lateral border of 1st rib under clavicle
Terminates at lateral border of first rib and becomes the axillary artery
What are the branches of the subclavian artery?
first part
- internal thoracic artery
- vertebral artery
- thyrocervical trunk (inferior thyroid artery, cervical artery, suprascapular artery)
second part
- dorsal scapular artery
- costocervical trunk (deep cervical artery, supreme intercostal artery)
third part
- no branches
What are the relations to the three parts of the subclavian artery?
1st part is posterior to left sternoclavicular joint
it is POSTERIOR to anterior scalene
Has its own groove on the first rib
and is posterior to the subclavian vein
What are the anatomical variants associated with the subclavian artery?
Aberrant left subclavian artery
Common stem of left subclavian artery + left common carotid artery
abberrant branches - of the vertebral artery and internal thoracic artery
What is the right subclavian artery and its function?
It is the artery to the posterior circulation (via the vertebral artery), posterior neck (via the costocervical trunk), chest wall (Via internal thoracic artery), and upper limb
Where does the right subclavian A sit?
Root of neck
intimately related to anterior scalene
What are the three parts of the right subclavian artery?
1st part - from origin to medial border of anterior scalene
2nd part - posterior to anterior scalene
3rd part - from lateral border of anterior scalene to first rib lateral border
What is the origin of the right subclavian artery?
One of the terminal branches of the brachiocephalic trunk.
What is the course of the right subclavian artery?
Ascends above anterior scalene (anterior) 1st part, and then posterior to it 2nd part. Then in direction towards the right first rib, under clavicle and then to lateral border of anterior scalene
How does the right subclavian artery terminate?
At the lateral border of scalene anterior - becomes the axillary artery
What are the branches of the right subclavian artery?
1st part
internal thoracic artery
vertebral artery
thyrocervical trunk - (inferior thyroid artery, transverse scapular artery, suprascapular artery)
2nd part
dorsal scapular artery
costocervical trunk - deep cervical artery, superior/supreme intercostal artery
3rd part
no branches
What are the key relations of the right subclavian artery?
Posterior to anterior scalene
Divided into 3 parts by anterior scalene
Posterior to subclavian vein
Has its own groove on first rib
What are the anatomical variations associated with the right subclavian artery?
aberrant right subclavian artery
diverticulum of kommerrell
aberrant branches - vertebral artery, internal thoracic artery specifically
What is specific about the course of the ABERRANT right subclavian artery?
travels posterior to oesophagus
What is specific about the course of the ABERRANT left subclavian artery?
with a right sided aortic arch
What are the anatomical variants associated with the subclavian artery?
vertebral artery - anomalous origin, asymmetry, duplication, fenestration, carotid basilar anastomoses, dominance
internal thoracic artery - anomalous in origin in 20 percent (so comes off 2nd part, 3rd part, or thyrocervical trunk)
Thyrocervical trunk, can come off second part or even third part
2nd part - dorsal scapular artery, costocervical trunk
What are the variations associated with the aortic arch?
bovine arch
right sided arch
coarctation of the aorta
patent ductus arteriosus
double aortic arch
ductus diverticulum
interrupted aortic arch
cervical aortic arch
What are the anatomical variants associated with big vessels?
bovine arch
left brachiocephalic trunk
aberrant origin of right subclavian artery
What are the anatomical variations associated with the small vessels?
inferior thyroid A comes off the aortic arch
thyroid ima artery comes off aortic arch
bronchial artery comes off the aortic arch
internal thoracic artery comes off the aortic arch
Where does the aortic arch sit?
T4-T5 level of the sternomanubrial joint
What is the function of the aortic arch?
Connects the ascending and descending aorta
With 3 vessels emerging superiorly (brachiocephalic trunk, L common carotid A, L subclavian A)
What is the course of the aortic arch?
Starts at the ascending aorta at T4-T5 level
Arches right to left posteriorly
Goes to the left of the trachea
terminates at the level of T4-T5 and becomes the descending aorta
What are the relations to the aortic arch?
Superiorly - left common carotid, left subclavian, brachiocephalic trunk
Inferiorly - ligamentum arteriosum, pulmonary trunk
Lateral - left lung
Medial - trachea, carina
Posterior - trachea, carina
Anterior - pleura, left lung
What are the muscles and ligaments involved with the aortic arch?
Ligamentum arteriosum - to the underside, remnant of ductus arteriosus
What are the anatomical variations in the aortic arch?
Bovine arch - where brachiocephalic shares origin with common carotid
Right sided arch
Hypoplastic aortic arch
Interrupted aortic arch
Patent ductus arteriosus
Coarctation of aorta
Cervical aortic arch
Ductus diverticulum
Double aortic arch
What is the thoracic duct?
It is the lymphatic drainage pathway for 3/4 of the body. Closely related to virchows node
Final common drainage pathway for lymphatics (apart from R) arm which drains to R) hemithorax)
If it gets blocked, leads to chylothorax
Where does the thoracic duct sit?
Sits at L1 - L2
cisterna chyli behind right diagphragmatic crus to root of neck to empty into left brachiocephalic vein (union of left subclavian vein + left internal jugular vein)
What is the origin of the thoracic duct?
Cisterna chyli at L1-L2
What is the course of the thoracic duct?
Goes through the aortic hiatus in the diagphram (with aorta, azygos vein, sympathetic trunk)
Ascends in the posterior mediastinum on the right hand side
with the azygos vein
crosses to the left side, behind oesophagus at T4-T5
passes posterior to left brachiocephalic vein
Final sentinel node - virchows node
Where does the thoracic duct terminates?
Terminates in the union of Left subclavian and left internal jugular vein - left brachiocephalic V
What are the tributaries to the thoracic duct?
lymphatics from the left arm, left hemi thorax, abdomen, pelvis and lower limbs
What are the relations to the thoracic duct?
Cisterna chyli is at L1-L2 - and under the right diagphramatic crus
runs through the aortic hiatus with the azygos vein
runs with azygos system and along right vertebral column
Crosses to left side and passes posterior to left brachiocephalic vein
What are the major relations to the thoracic duct?
Anterior: oesophagus
Posterior: vertebrae, intercostal arteries, intercostal veins
Lateral: as it ascends, the descending aorta will be on the left.
What are the anatomical variants associated with the thoracic duct?
Double thoracic duct
Abnormal course - duct can run up right side and not cross T4-T5
Duct can run up right side, and empty into right IJV
Aberrant termination into
RIght IJV
Right brachiocephalic vein
Right EJV
Right subclavian vein
Azygos vein
Hemiazygos vein
What is the breast?
It is a modified sweat gland.
Responsible for milk production for infants.
Sits anterior to pectoralis major.
Overlies ribs 2-6 in the non pendulous breast
What is the gross anatomy of the breast?
It is made up of mostly fat tissue
Suspended by ligaments of cooper
Has an axillary tail
15-20 lobes which drain to lactiferous ducts
Lactiferous ducts drain to the nipple areolar complex
What are the relations of the breast?
Posterior - pectoralis major, intercostal nerve, artery, vein
Medial - Sternum, internal thoracic artery and vein
Lateral - mid axillary line, long thoracic nerve, lateral thoracic artery
Inferior - costal margin, superior epigastric A, musculophrenic A
What is the arterial supply of the breast?
Medial - medial mammary perforators. Come off the internal thoracic A (comes off 2nd part subclavian)
Lateral - lateral mammary perforators. Come off the lateral thoracic artery (second part of axillary artery)
Deep - intercostal arteries (2-6)
What is the venous drainage of the breast?
Mirrors the arterial supply
internal thoracic vein
Axillary vein
Intercostal vein
What is the lymphatic drainage of the breast?
The lymphatic drainage of the breast - typically drains to the periareolar plexus (Sappey’s) before going to the sentinel node.
Does 75 percent of the drainage
Level 1 - lateral to pec minor
Level 2 - posterior to pec minor
Level 3 - medial to pec minor
Internal thoracic pathway
Retromammary pathway
lymphatics cross to the contralateral breast, to the rectus sheath and peritoneum which is relevant and key to spread
What is the nerve supply to the breast?
T3- T5 intercostal nerves
What are the muscles/ligaments/fascia involved with the breast?
Suspensory ligaments of cooper
pectoralis major (breast sits anterior)
pectoralis minor (divides up the axillary lymph nodes)
What are the anatomical variants associated with the breast?
Supernumeray nipple
Polymastia
Breast hypoplasia
Amastia
What do the axillary pathway, internal mammary and retromammary nodes run with?
Internal mammary - internal thoracic vessels
Retromammary - intercostal vessels 2 -6
Axillary - runs with axillary vein
What is the general pathway of lymphatic drainage of the breast?
Goes from superficial to deep, to sappey’s plexus to sentinel LN
What is the origin, course, and termination of the brachiocephalic vein?
Origin: internal jugular vein + subclavian vein
Course: through root of neck
Terminates: unite to form superior vena cava
What are the tributaries to the brachiocephalic vein?
internal thoracic vein
internal jugular vein
Subclavian vein
thoracic duct / Right lymphatic duct
What is the origin, course and termination of internal thoracic vein?
Origin - union of musculophrenic vein and superior epigastric vein
Course - lateral to sternum, (with internal thoracic artery)
runs in neurovascular plane, between transverse thoracus and innermost intercostal
terminates - drains to brachiocephalic vein
What is the origin, course and termination of the superior vena cava?
Origin - union of the brachiocephalic veins
Course - from union to right atrium
Terminates - into the right atrium
Tributaries- brachiocephalic veins, azygos vein, hemiazygos system
What is the origin, course and termination of the inferior vena cava?
Origin - union of common iliac veins
Travels through the retroperitoneum and then through the hiatus in the diagphram at T8 with phrenic N
Terminates at the right atrium
What are the tributaries to the inferior vena cava?
Common iliac veins
Lumbar veins
Hepatic veins
Renal veins
Right gonadal vein
What is the origin, course, termination of the azygos vein?
Origin - union of the right intercostal veins (2-11)
Course ascends down to the right of the vertebral column, through the diagphramatic hiatus at T12
Terminates by emptying into SVC
What is the origin, course and termination of the hemiazygos veins?
Origin: the fusion of the lower 4 left intercostal veins and ascending lumbar veins
ascends in the posterior mediastinum to the left of the vertebral bodies crosses at T8
Drains into azygos system
What is the origin, course, termination of the accessory hemi azygos vein?
Origin: involves the union of the left sided intercostal veins (4-8)
Left intercostal veins 1-3 drain into superior intercostal vein
descends into posterior mediastinum
Drains into azygos system
Also has oesophageal and pericardial tributaries
Summary of venous drainage of the thorax?
azygos - goes through aortic hiatus at T12 with the thoracic duct, also crosses over right hilum
hemiazygos / accessory hemiazygos - drain at T8
IVC - goes through the foramen at T8 with the R) phrenic N
What is the gross anatomy of the lungs?
Right lung has 3 lobes - 10 segments
Left lung has 2 lobes - 8 segments
Left lung is indented by the heart
Joined at hilum - pulmonary vein, artery and bronchus enter
What are the two zones involved with the lungs?
Conduction zone - warms and humidifies air
Respiration zone - gas exchange, at terminal bronchioles
What is the arterial supply of the lungs?
Bronchial arteries - oxygenated blood from aorta
Pulmonary arteries - take deoxygenated blood from RV
What is the venous drainage of the lungs?
Bronchial veins - proximal
Pulmonary veins - peripheral
What is the lymphatic drainage of the lungs?
intrapulmonary lymph node
drain bronchopulmonary nodes -> hilar nodes (stations 8, 9, 10)
What is the nerve supply of the lungs?
the pulmonary plexus
Sensation is phrenic medially
and intercostals laterally
What are the muscles/ligaments and fascia involved with the lung?
Lined by visceral pleura
In contact with parietal pleura
(costophrenic recess inferolaterally)
pulmonary ligament - double folding of pleura at hilum
What are the anatomical variations associated with the lungs?
inferior accessory fissure
superior accessory fissure
azygos fissure
oesophageal lung
pulmonary aplasia
minor fissure of the lung
Where do the pulmonary veins sit?
Sit in the hilum with the artery and main bronchi
Sit in the mediastinum
V- A - T (anterior to posterior)
What is the gross anatomy of the venous drainage of the lung?
Dual venous drainage - bronchial veins + pulmonary veins
What is the origin, course and termination of the bronchial veins?
Drain the proximal lung
Runs posterior to the main bronchi
Drain to the azygos vein on RIGHT
Drain to the hemiazygos + accessory hemiazygos on LEFT
Communicate with the pulmonary veins
What are the pulmonary veins?
Right superior pulmonary veins (RUL, RML)
Right inferior pulmonary vein (RLL)
Left superior pulmonary vein (LUL)
Left inferior pulmonary vein (LLL)
The course of all pulmonary veins is that they run in vein, artery, tube configuration to the hilum. (Veins inferior, artery superior)
Pulmonary veins terminate in the left atrium.
What are the contents of the pulmonary veins?
Contain oxygenated blood - carry blood to left atrium.
What is the difference between the pulmonary veins and bronchial veins?
Pulmonary veins run in vein - artery - tube configuration
Bronchial veins are adherent to bronchi - stuck to posterior surface
What are the relations of the pulmonary veins?
Anterior: posterior border of heart, phrenic N, lymph nodes
Posterior: pulmonary arteries, main bronchi, lymph nodes
Superior: SVC on the right, arch of aorta on the left
Inferior: pulmonary ligament, L atrium / ventricle posterior border
Medial: left atrium
Lateral: visceral pleura, lung
What is the lymphatic drainage of the pulmonary veins?
Bronchopulmonary nodes
hilar lymph nodes
What are the anatomical variants associated with the pulmonary veins?
Acccessory pulmonary veins
Common trunks of pulmonary veins
Anomalous pulmonary veins
- some pulmonary veins drain into the systemic circulation rather than the left atrium- this is associated with ASD
Total anomalous pulmonary venous return
Partial anomalous pulmonary venous return
What is the function of the pulmonary arteries?
Part of vascular system which delivers deoxygenated blood from the right ventricle to the lungs for gas exchange.
Where do the pulmonary arteries sit?
In the mediastinum. Pulmonary veins sit anterior, bronchi sit posterior.
What is the origin, course and termination of the pulmonary arteries?
Origin: starts at the right ventricle
Course: continues as the pulmonary trunk, which sits infront of the left main bronchus
Terminates: into the right and left pulmonary arteries
What is the origin, course and termination of the left pulmonary artery?
Origin: pulmonary trunk,
Course: runs anteriorly and superiorly over left main bronchus
Terminates: Left ascending trunk + left descending trunk
What is the origin, course, and termination of the right pulmonary artery?
origin: pulmonary trunk
course: runs anteriorly over right main bronchus
terminates: right ascending trunk + interlobar artery which will divide again to supply the right middle lobe + right lower lobe
What are the relations of the pulmonary arteries?
Anterior: pulmonary vein, phrenic nerve
Posterior: main bronchus
Superior: SVC on the right, aortic arch on the left + ligamentum arteriosum
Inferior: pulmonary ligament
What are the muscles and ligaments involved with the pulmonary arteries?
Ligamentum arteriosum - remnant of the ductus arteriosus, responsible for connection (fibrous band) between the pulmonary trunk / left pulmonary artery to the aortic arch.
What are the anatomical variants associated with the pulmonary artery?
Aberrant pulmonary artery - pulmonary sling
pulmonary artery aneurysm
pulmonary artery atresia
What is the SVC?
One of the great vessels which is responsible for returning of the deoxygenated blood from the superior half part of the body
Is partially covered by pericardium
What is the origin, course and termination of the superior vena cava?
Origin: union of the two brachiocephalic veins
Course: runs down from union toward right atrium, posterior and to the right of the menubrium
Also recieves azygos vein at this point
Termination: into the right atrium
What are the tributaries to the superior vena cava?
azygos vein
vertebral venous system
internal thoracic vein
right superior intercostal vein
What are the relations to the superior vena cava?
Anterior: ascending aorta, thymus, sternum
Posterior: azygos vein
Medial: pre-carinal lymph nodes
Lateral (right): parietal pleura and lung
Lateral (left): aortic arch
What are the anatomical variations associated with SVC?
Left sided SVC
SVC duplication
Absent SVC
What is found on each surface of the heart?
Anterior: Right atrium, Right ventricle
Posterior: Left atrium, great vessels (veins)
Left: Left ventricle
Apex: left ventricle
Right: right ventricle
Inferior: central tendon, left ventricle, right ventricle
What is the valvular anatomy of the heart?
Mitral valve - LA
Aortic valve - LV - thickened myocardium compared to right
Tricuspid valve - RA
Pulmonary valve - RV - in contact with sternum
What is the relations of the heart?
Anterior: sternum, lungs, pleura, right heart is in contact with sternum
Posterior: Descending aorta, hemi azygos vein on the left, azygos vein on the right
Superior: SVC, pulmonary trunk
Inferior: diaphgram
Lateral: lungs / pleura
What is the arterial supply to the heart?
Coronary arteries
What is the venous drainage of the heart?
coronary veins
pulmonary veins
drain to IVC / SVC
What is the nerve supply of the heart?
Cardiac plexus
Sensation is T1-T5
What are the main coronary arteries of the heart?
Right coronary artery + Left coronary artery
Arise from the aortic sinus
Travel in respective atrioventricular groove
Coronary artery which gives off the posterior descending artery (usually the RCA) is usually the dominant one
Give off blood in diastole
What are the branches of the left coronary artery?
Left circumflex artery- gives off obtuse marginal A
Travels in the left atrioventricular groove
Left anterior descending artery - gives off diagonal branches + septal branches
Travels in anterior interventricular groove
Can have ramus intermedius if there is a trifurcation
What are the branches of the right coronary artery?
Right coronary artery travels in right atrioventricular groove
sinoatrial nodal artery
posterior descending branch - travels in posterior interventricular groove
acute marginal branches
conus artery (like LAD)
What is the dominant coronary artery?
Whichever gives off the posterior descending artery is the dominant artery
Right sided dominance - 70 percent
Left sided dominance - 20 percent (from left circumflex)
Co dominance - 10 percent
What are the accessory arteries associated with the coronary arteries?
Accessory arteries
- conus A (on right side)
- ramus intermedius (on left side)
What are the anatomical variants associated with the coronary arteries?
Dominance
Accessory
RCA can have origin from left aortic sinus
LCA can have origin from right aortic sinus
RCA can come from LCA and move across the RVOT - malignant!
RCA can come from LCA and run posterior to aorta - anomalous posterior LCA
LCx from RCA - anomalous circumflex
Abberant course - RCA + LCA moving to the RVOT + aorta are malignant variants and can be squished!
Absence of posterior descending artery - can have RCA or LCA branches, or have a large LAD which curves over apex
What is a summary of the veins and coronary arteries with respect to the grooves?
Left Coronary Artery - runs in left atrioventricular groove
Left Circumflex Artery - runs with left atrioventricular groove, and with great cardiac vein
Right Coronary Artery - runs in right atrioventricular groove, runs with small cardiac vein
Left anterior descending artery - runs in anterior interventricular groove, runs with great cardiac vein
Right posterior descending artery - runs in posterior interventricular groove, runs with middle cardiac vein
What is the coronary sinus?
It is an enlargement that follows the great cardiac vein
It runs in the posterior atrioventricular groove
Terminates into the right atrium
What are the branches / tributaries to the coronary sinus?
Small cardiac veins
Middle cardiac vein
Great cardiac vein
Where does the great cardiac vein run?
Great cardiac vein
Runs in the left atrioventricular groove
- assoc with LCA, LCx
- Also runs with the LAD inferiorly and Left circumflex as it wraps around the heart margin
Where does the middle cardiac vein run?
Middle cardiac vein runs in posterior interventricular groove
So accompanies posterior descending artery
Where does the small cardiac vein run?
Small cardiac vein runs in the right atrioventricular groove
So accompanies RCA
What are the anterior cardiac veins?
Anterior cardiac veins / thesbian veins
Drain anterior surface of the heart
Drain straight to right atrium
What is the pericardium?
It is a conical sac which encloses the heart and its great vessels
Secretes pericardial fluid and allows for a frictionless surface for the heart to move
What is the gross anatomy of the pericardium?
Two coats
Serous pericardium - inner coat
Outer pericardium - fibrous coat
Continuous inferiorly with the conjoint tendon
continuous superiorly with roots of great vessels
What are the pericardial reflections and sinuses?
Reflections of the pericardium create the sinuses and recesses.
Transverse sinus - behind the arch of aorta + pulmonary trunk. Also has the pulmonary arteries superiorly, pulmonary veins inferiorly
Oblique sinus - between left atrium and oesophagus
What are the pericardial recesses?
Anterior superior aortic recess
Posterior superior aortic recess
Pulmonary venous recess
Post caval
What is the contents of the pericardial sinuses and recceses?
pericardial fluid
What are the relations to the pericardium?
Anterior: sternum
Posterior: oesophagus
Superior: base of great vessels
Inferior: central tendon
Lateral: phrenic N, pericardiophrenic artery + vein, pleura
What is the arterial supply of the pericardium?
Internal thoracic artery
- pericardiophrenic A
- musculophrenic A
What is the venous drainage of the pericardium?
Internal thoracic vein
- pericardiophrenic V
- musculophrenic V
What is the nerve supply of the pericardium?
Phrenic N
Vagus N
Sensation - T1-5
What are the anatomical variants associated with the pericardium?
Pericardial agenesis
What is the pleura?
Two layered sac which lines the lungs + thoracic cavity
Has pleural fluid to create frictionless surface for lungs to move
IntraPleural space is negative pressure - which the diagphram contracts for to allow lungs to fill with air
What is the gross anatomy of the pleura?
Parietal pleura - lines the thoracic cavity
Visceral pleura - lines the lung parenchyma
Pleura join at the lung hilum
Pleura is free and unprotected at the lung apices, costoxiphisternal angle, costodiagphmatic recess
Pleura invaginates the lung lobes and lines the fissures
What are the boundaries of the pleura?
Rib 2-4-6- runs adjacent to sternum
Rib 8 - runs to mid clavicular line
Rib 10 - runs to mid axillary line
Rib 12 - most posterior space, costovertebral angle
What is the arterial supply of the pleura?
Bronchial arteries (visceral)
Intercostal arteries (parietal)
What is the venous drainage of the pleura?
Bronchial veins (visceral)
Intercostal vein (parietal)
What is the lymphatic drainage of the pleura?
Bronchopulmonary nodes which drain to hilar lymph nodes
Can drain to axillary /mediastinal lymph nodes
What is the nerve supply of the pleura?
Parietal pleura - T2-T6 from adjacent intercostals
Visceral pleura - insensate!
What are the muscles / ligaments / fascia involved with the pleura?
pulmonary ligament
invaginates lung lobes to line the fissures
What are the anatomical variants associated with the pleura?
Superior accessory fissure
Inferior accessory fissure
Azygos fissure
minor fissure of left lung or incomplete fissure
What is the diagphram?
Dome shaped muscle
Demarcates the thorax and abdominal cavities
An essential organ of respiration which changes the intrapleural pressure to expand the lungs
Where does the diaphragm sit?
In the same plane as transversus abdominis
What is the gross anatomy of the diagphram?
Origin: sternum, costal cartilages
Inserts: onto central tendon
Fuses superiorly with pericardium
Covered superiorly by pleura and inferiorly by peritoneum
What are the contents of the diagphram?
T8 - IVC, RIGHT phrenic N
T10 - vagus N, oesophagus, left gastric artery + vein
T12 - aorta, thoracic duct, azygos
Minor apertures-
Left dome - left phrenic N
medial arcuate ligament - sympathetic chain
lateral arcuate ligament - subcostal artery + nerve
Laterally - the intercostal artery + veins and nerves become the thoracoabdominal artery + veins + nerves T7-T12
Anteriorly - superior epigastric artery + vein
What are the relations of the diagphram?
Anterior: sternum
Lateral: costal margin
Posterior: vertebra
What is the arterial supply of the diagphram?
internal thoracic artery + musculophrenic artery
intercostal artery
inferior phrenic artery + superior phrenic artery
What is the venous drainage of the diagphram?
internal thoracic vein, musculophrenic vein
intercostal vein
azygos and hemiazygos vein
inferior and superior phrenic veins
What is the lymphatic drainage of the diagphram?
phrenic lymph nodes
Bare area of the liver lymphatics communicate with the diagphram
What is the nerve supply of the diagphram?
motor - phrenic N (C3,4,5)
sensory - phrenic N centrally, intercostal N peripherally
What is the muscular ligaments / fascia / supply involving the diagphram?
Left crus L2 - L3
right crus L1 - L3
median arcuate ligament (goes over aorta)
lateral arcuate ligament (goes over psoas)
covered superiorly by pleura
covered inferiorly by peritoneum
central tendon is also fused superiorly with pericardium
What are the anatomical variants associated with the diagphram?
accessory diagphram
duplicated diagphram
muscular slips
diagphramatic eventration
dromedary diagphram
scalloped diagphram
What are the congenital diagphramatic herniation sites?
Morgagni
hiatus hernia
Bochladek
Eventration
What is the internal thoracic artery?
Internal thoracic artery is the artery to the anterior chest wall
It is a vertical anastomosis between the subclavian artery + external iliac artery
Where does the internal thoracic artery sit?
Posterolateral to sternum
In the neurovascular plane of the thorax - between the innermost intercostal and transversus thoracis
What is the gross anatomy of the internal thoracic artery?
Comes off first part of subclavian A.
Then courses posterior to the first rib, through the superior thoracic aperture, posterolateral to the sternum and in the neurovascular plane of transversus thoracis + innermost intercostals
Goes through the anterior aperture of the diapghram and divides into the superior epigastric artery + musculophrenic artery
What does the internal thoracic artery supply?
Anterior chest wall
Medial breast
Diagphram
Pericardium
What are the branches of the internal thoracic artery?
Superior epigastric A
Musculophrenic A
Medial perforators to the breast
pericardiophrenic A (with phrenic N)
What are the relations to the internal thoracic artery?
pericardiophrenic A Runs with the phrenic N
internal thoracic vein
What are the anatomical variations associated with the internal thoracic artery?
can come off 2nd part of subclavian instead of 1st
can come off 3rd part of subclavian instead of 1st
can come off thyrocervical trunk branch
CAN TRIFURCATE and give a branch to xiphoid (as well as superior epigastric + musculophrenic)
Fun facts about internal thoracic A
It is resistant to atherosclerotic disease so often used for CABG graft
Is a subclavian - external iliac anastomosis
Where do the internal thoracic A vs intercostal A run?
Internal thoracic runs in the innermost - transversus thoracis plane
Intercostal A runs in the internal and innermost plane
What is the boundary of the cervical oesophagus?
from cricopharyngeus C6 to superior thoracic aperture T1
What is the boundary of the thoracic oesophagus?
from superior thoracic aperture T1 to oesophageal hiatus T10
What is the boundary of the abdominal oesophagus?
From oesophageal hiatus T10 to blending of cardia with stomach at GOJ
What are the three main parts of the oesophagus?
Cervical part - from cricopharyngeus C6 to superior thoracic aperture T1
Thoracic part - from superior thoracic aperture T1 to oesophageal hiatus T10
Abdominal part - from oesophageal hiatus T10 to blending of cardia with stomach at GOJ
What are the three physiological narrowings of the oesophagus?
Cervical - cricopharyngeus at C6
Thoracic - arch of aorta + left main bronchus
Abdominal - oesophageal hiatus T10
What is the course of the oesophagus?
Continuous with the inferior oropharynx and cricopharyngeus
Goes down posterior mediastinum
through the oesophageal hiatus of diagphram at T10 - and then blends with cardia of stomach
What is the arterial supply of the oesophagus?
Cervical - inferior thyroid artery
Thoracic - oesophageal branches of aorta / bronchial artery
Abdominal - left gastric artery
What is the venous drainage of the oesophagus?
Cervical - inferior thyroid vein (drains to brachiocephalic vein)
Thoracic - to azygos vein
Abdominal - left gastric vein (drains to portal vein)
What is the lymphatic drainage of the oesophagus?
Cervical - to deep cervical chain
Thoracic - to posterior mediastinum
Abdominal - coeliac / left gastric lymph nodes
What is the nerve supply of the oesophagus?
upper 1/3 - recurrent laryngeal N
lower 2/3 - oesophageal plexus (from vagus N)
We know the vagus nerve descends adjacent to the oesphagus and the left becomes the anterior vagal plexus, the right becomes the posterior vagal plexus
What are the muscles / ligaments / fascia involved with the oesophagus?
cricopharyngeus at C6 (which it is continuous with)
diagphramatic crus (left and right)
What are the anatomical variants associated with the oesophagus?
oesophageal atresia (when the foregut does not divide into the trachea anteriorly and the oesophagus posteriorly)
oesophageal bronchus - when a bronchus arises directly from the oesophagus
aberrant Right subclavian artery - can go anterior or posterior around oesophagus
What are the relations to the cervical oesophagus?
Anterior: Trachea, larynx, tracheooesophageal groove (anterolateral)
Posterior: vertebral column
Lateral: tracheooesophageal groove, recurrent laryngeal N, parathyroids, paratracheal nodes
*carotid sheath (contains medial to lateral, carotid A, vagus N, internal jugular vein)
Superior: cricopharyngeus, oropharynx
What are the relations to the thoracic oesophagus?
Anterior: arch of aorta (T4), left main bronchus (T5), left atrium, left ventricle
Posterior: thoracic duct, descending aorta (posterolateral on left), vertebral column, sympathetic trunk
Lateral: superiorly, recurrent laryngeal nerve, lungs and pleura
What are the relations to the abdominal oesophagus?
Abdominal oesophagus will blend with the cardia of the stomach
Oesophageal hiatus (T10)
What structures go through the oesophageal hiatus together?
Oesophagus
Left gastric artery + vein
Vagus N
What are the anatomical variants associated with C7?
Transverse foramen of C7 is small. Can also be absent. Vertebral artery can be travelling through the foramen
Transverse process of C7 can be bifid.
Body of C7 can have a caudal pit for the head of first rib
What are the issues existing with cervical rib?
fully formed, or merely enlargements of a costal process
Can articulate with the sternum
Can be unattached at its distal (ventral) end
Can compress blood vessels - subclavian A + V
Can compress nerves - brachial plexus
Can terminate in a dense fibrous band
Can be associated with pre or post fixed cervical plexus
What is the sternal angle?
Sternal plane runs in the T4-T5 intervertebral space
The sternal angle runs from the manubriosternal joint to the T4-T5 intervertebral disc space
Sternal angle happens here
Sternal angle defines the superior and inferior mediastinum
What occurs at the thoracic plane (T4/T5)?
CLAPTRAP
Cardiac plexus
Ligamentum arteriosum
Aortic Arch (beginning and end)
Pulmonary trunk
Trachea (bifurcation at carina)
Right - to- left movement of thoracic duct (posterior to oesophagus)
Azygos vein drains to SVC (over right main bronchus)
Pre vertebral fascia and pre tracheal fascia end
What is the gross anatomy of the pulmonary hilum?
Pulmonary vein (most inferior)
Pulmonary artery
Bronchi (most superior)
Phrenic nerve courses anterior to the pulmonary hilum
Vagus nerve courses posterior to the pulmonary hilum
Pulmonary ligament hangs inferiorly as a double reflection of pleura - in the pulmonary ligament - hangs the pulmonary lymph nodes
What is the origin of the recurrent laryngeal nerve?
Comes from the vagus N
What is the course of the recurrent laryngeal N?
On the left side, hooks over the arch of aorta
On the right side, hooks under right subclavian artery
Ascends in the tracheooesophageal groove
Deep to posteromedial surface of thyroid
Terminates at the larynx at the inferior constrictor
What is the supply of the recurrent laryngeal nerve?
Motor to all the intrinsic muscles of larynx (except cricothyroid)
And we know posterior cricoarytenoid (is the most important muscle as it is the only one that adducts the vocal folds)
Sensory to everything below the vocal cords
What are the relations of the recurrent laryngeal nerve?
thyroid gland (anterior)
inferior thyroid artery
What is the vagus nerve?
major parasympathetic innervation to the thorax and abdomen. Has motor and sensory fibres
Where does the vagus nerve sit?
posterolateral sulcus of the medulla
Jugular foramen
carotid sheath
posterior mediastinum
Oesophageal hiatus of the diaphgram
vagal plexus
What is the course of vagus nerve?
Begins at the cistern (interpeduncular)
then jugular foramen
carotid sheath
and splits into the right and left vagus nerve at the root of the neck
What is the course of the right vagus nerve?
over right subclavian artery
posterior to R) lung hilum
Runs down oesophagus
Terminates as posterior vagal plexus
What is the course of the left vagus nerve?
Lateral to aortic arch
Posterior to lung hilum
Runs down oesophagus
terminates as anterior vagal plexus
What are the branches of the left and right vagus nerve?
recurrent laryngeal nerve
- muscular supply to larynx (EXCEPT CRICOTHYROID)
- sensation inferior to vocal cord
What are the relations of the vagus nerve with respect to its course?
in the brain
- it is in the posterolateral sulcus of medulla
- between CN IX and spinal nucleus of CN XI
in the jugular foramen
- will run with the internal jugular vein
in the carotid sheath
- will run as the most posterior structure. IJV is lateral and then ICA / CCA is medial
- runs down on belly of anterior scalene
in the posterior mediastinum
- R VAGUS nerve - is between the subclavian A and brachiocephalic V
- L VAGUS nerve - is anterolateral to arch of the aorta, and posterior to brachiocephalic vein
in the thorax/abdomen
- intimately related to the oesopahgus
- passes through oesophageal hiatus
What is the pathway for the conducting system of the heart?
SA node -> internodal fibres -> AV node -> bundle of his -> purkinje fibres
What is the blood supply to the SA and AV node?
Right coronary artery
What is the nerve supply to the heart?
cardiac plexus
T1-T5 is sensation
Cardiac plexus - has deep and superficial supply
Cardiac plexus has both parasympathetic and sympathetic inputs
What are the relations of the electrical conductivity of the heart?
SA node - anterior to SVC
AV node - in interatrial septum
Bundle of his - in interventricular septum
Purkinje fibres - in myocardium
Annulus fibrosus - surrounds the valves
** each cardiac cell is a potential pacemaker cell
intrathoracic nodal stations and landmarks used to define them:
2 with ‘mediastinal’ in their name
o Highest – above brachiocephalic vein
o Upper – above aortic arch
o 2 with ‘tracheal’ in their name
o Retrotracheal (prevascular) – in front of vessels and in front of vertebrae
o Lower paratracheal – adjacent to trachea (superior to carina)
o 2 with ‘aortic’ in their name
o Sub-aortic – lateral to ligamentum arteriosum
o Para-aortic – lateral to aortic arch
o 2 below carina in midline
o Subcarinal – inferior to carina (note how the sub-carinal node does not immediately follow the ‘tracheal’ nodes)
o Para-oesophageal – lateral to oesophagus
o 2 laterally at the hilum!
o Pulmonary ligament – in pulmonary ligament, posteroinferior to pulmonary vein
o Hilar – with pulmonary vein/artery/bronchi
What are the relations to all the interthoracic nodes?
- Highest mediastinal (supraclavicular, sternal notch, low cervical)
a. Lie superior to left brachiocephalic vein - Upper mediastinal (upper paratracheal LN)
a. Lie above aortic arch - Prevascular /retrotracheal
a. In front of vessels / posterior to trachea (pre-vertebral) - Lower paratracheal
a. Below aortic arch inferior margin, but above main bronchi - Sub-aortic
a. Lateral to ligamentum arteriosus/ascending aorta - Para-aortic
a. Lateral to arch of aorta (think of barry comment on missed LN)
i. N.B. para-aortic LN are actually superior sub-aortic!) - Subcarinal
a. Inferior to carina (below T4/5) - Para-oeosphageal
a. Adjacent to eosophagus - Pulmonary ligament
a. In pulmonary ligament, posteroinferior to pulmonary vein - Hilar
a. With bronchus / pulm a / pulm v
What are the muscles in a typical intercostal space?
External intercostal
Inner intercostal
Innermost intercostal
- between the inner and innermost intercostal is the neurovascular bundle. runs in a costal groove on the inferior side of rib
What is contained in the intercostal NV bundle?
intercostal A (comes off aorta), anastomoses with internal thoracic A anteriorly
gives an anterior, lateral, and posterior branch
anterior perforating, lateral and posterior intercostal
Intercostal Vein - drains to azygos / hemi / accessory azygos
Intercostal nerve - made from anterior ramii of spinal nerves
What are the relations to the intercostal space?
Medially the lungs and pleura!
