Thorax Flashcards
How is the mediastinum divided into 2 parts
By an imaginary line running between the sternal angle and T4
Divides the mediastinum into superior and inferior
Where does the superior mediastinum extend to
Upwards, terminating at the superior thoracic arpeture
Where does the inferior mediastinum extend to
Downwards, terminating at the diaphragm
What is the inferior mediastinum further divided into
Anterior, middle and posterior mediastinum
What are the borders of the superior mediastinum
Superior - thoracic inlet
Inferior - Continuous with the inferior mediastinum at the level of the sternal angle
Anterior - manubrium of the sternum
Posterior - vertebral bodies of T1-4
Lateral - pleural of the lungs
Which vessels are found within the superior mediastinum
Arch of aorta and the following branches:
-Brachiocephalic a
- Left common carotid a
- Left subclavian
SVC and the following tributaries
- Brachiocephalic veins
- Left superior intercostal vein
- Supreme intercostal vein
- Azygos vein
Which nerves are found within the superior mediastinum
Phrenic nerve
Vagus nerve
Cardiac nerves
Sympathetic trunk
Which organs and muscles are found in the superior mediastinum
Thymus
Trachea
Oesophagus
Thoracic duct
Muscles - sternohyoid and sternothyroid
What is the borders of the anterior mediastinum
Lateral - mediastinal pleura
Anterior - body of sternum and transversus thoracis muscles
Posterior - pericardium
Roof - continuous with superior mediastinum at the level of the sternal angle
Floor - diaphragm
In which part of the mediastinum is there no major structures
Anterior mediastinum
What are the borders of the middle mediastinum
Anterior - Anterior margin of the pericardium
Posterior - posterior margin of the pericardium
Laterally - Mediastinal pleura of the lungs
Superiorly - imaginary line between the angle of mandible and T4
Inferiorly - surface of diaphragm
What are the contents of the middle mediastinum
Heart and pericardium
Tracheal bifurcation into left and right bronchi
Ascending aorta
Pulmonary trunk
SVC
Cardiac plexus
Phrenic nerves
Tracheobronchial lymph nodes
What are the borders of the posterior mediastinum
Lateral - mediastinal pleura
Anterior - pericardium
Posterior - T5-T12 vertebrae
Roof - imaginary line between the angle of mandible and T4
Floor - diaphragm
What is contained within the posterior mediastinum
Thoracic aorta
Oesophagus
Thoracic duct
Azygous system of veins
Sympathetic trunks
What are the 3 major veins of the azygous system of veins
Azygos vein
Hemiazygos vein
Accessory hemiazygos vein
What does the thoracic duct originate from and where does it enter the thorax
Cisterna Chylii
Enters the thorax via the aortic hiatus (T12)
What arteries branch from the aorta in the posterior mediastinum
Posterior intercostal arteries
Bronchial arteries
Oesophageal arteries
Superior phrenic arteries
What can the aorta be divided into
Ascending aorta
Aortic arch
Descending aorta
Abdominal aorta
What are the branches of the ascending aorta
Left and right aortic sinuses which give rise to the right and left coronary arteries
At what level does the aortic arch end
T4
What connects the aortic arch to the pulmonary trunk
Ligamentum arteriosus
What are the branches of the aortic arch
Left common carotid
Left subclavian
Brachiocephalic trunk
At what point does coarctation of the aorta usually occur
At the insertion of the ligamentum arteriosus
From which vertebral levels does the descending aorta span
T4 - T12
What are the paired branches of the descending aorta
Bronchial arteries
Mediastinal arteries
Oesophageal arteries
Pericardial arteries
Superior phrenic arteries
Intercostal and subcostal arteries
What are the paired branches of the abdominal aorta
Inferior phrenic arteries
Middle suprarenal arteries
Renal arteries
Gonadal arteries
Lumbar arteries
What are the unpaired branches of the abdominal aorta
Coeliac axis
SMA
IMA
Medial sacral artery
What are the unpaired branches of the descending aorta
Bronchial arteries
Mediastinal arteries
Oesophageal arteries
Pericardial arteries
What does the abdominal aorta bifurcate to form
right and left common iliac
What does the SVC form from
The union of the left and right brachiocephalic trunks
Through which part of the mediastinum does the SVC pass
Superior mediastinum
At which level does the SVC receives the azygos vein
T4
Which pharyngeal pouch is the thymus developed from
Third
Where is the thymus located
In the superior mediastinum, immediately posterior to the manubrium of the sternum
What is the blood supply of the thymus
Anterior intercostal arteries and small branches of the internal thoracic arteries
Venous drainage - left brachiocephalic and internal thoracic veins
In which syndrome does thymic aplasia occur
DiGeorge Syndrome
The breast can be considered in 2 regions, what are these
Circular body
Axillary tail
What are the anatomical structures of the breast
Mammary glands
Connective tissue stroma
Pectoral fascia
What forms the suspensory ligaments of Cooper and what are their function
Fibrous stroma condenses down to form the suspensory ligaments of Cooper
Function - Attach and secure the breast to the dermis and underlying pectoral fascia.
Separate the secretory lobules of the breast.
What does the base of the breast lie on and what attaches here
Pectoral fascia
Suspensory ligiaments of Cooper attach here
What is the blood supply of the breast
60% - internal mammary artery (internal thoracic)
Lateral thoracic and thoracoarcromial
Lateral mammary branches
Mammary branch
What is the venous drainage of the breast
Axillary and internal thoracic veins
What is the lymph drainage of the breast
Axillary nodes - 75%
Parasternal nodes - 20%
Posterior intercostal nodes - 5%
What is the nervous innervation of the breast
Anterior and lateral cutaneous branches of the 4th-6th intercostal nerves
At what level does the pulmonary trunk split into the right and left pulmonary arteries
T5-T6
How does the anatomy of the right and left inferior pulmonary veins differ
Inferior left pulmonary vein - found at the hilum of the lung
Inferior right pulmonary vein - runs posteriorly to the SVC and the right atrium
At what level does the IVC enter the thorax
T8
What are the 2 parts of the right atrium and what separates them
Sinus venarum
Atrium proper
Separated by the crista terminalis
Which part of the right atrium has smooth walls and receives blood from the SVC and IVC
Sinus Venarum
Which ventricle forms the majority of the anterior border of the heart
Right
What divides the right ventricle into an inflow and outflow portion
Supraventricular crest
What are trabeculae carnae
A series of irregular muscular elevations which are found in the ventricles of the heart
What is the conus arteriosus
The outflow portion of the right ventricle - it is smooth
What is the aortic vestibule
The outflow portion of the left ventricle
Where does the coronary sinus open into
the right atrium between the inferior vena cava orifice and the right atrioventricular orifice.
Where is the SAN found
The upper wall of the right atrium, at the junction where the superior vena cava enters
What is the fibrous pericardium continuous with
The central tendon of the diaphragm
What are the layers of the pericardium
Fibrous layer
Parietal layer of serous pericardium
Serous fluid
Visceral layer of serous pericardium
Where is the transverse pericardial sinus found
Posterior to the ascending aorta and pulmonary trunk
Anterior to the SVC
Superior to the left atrium
What is the innervation of the pericardium
Phrenic nerve
What is the anterior surface of the heart
Right ventricle
What is the posterior surface of the heart
Left atrium
What is the inferior surface of the heart
Left and right ventricles
What are the 3 main sulci of the heart
Coronary sulcus
Anterior interventricular sulcus
Posterior interventricular sulcus
What is found in the coronary sulcus of the heart
The right coronary artery
Circumflex branch of the left coronary artery
Small cardiac vein
Coronary sinus
What is found in the anterior interventricular sulcus of the heart
Anterior interventricular artery (also known as the left anterior descending artery)
Great cardiac vein
What is found in the posterior interventricular sulcus of the heart
posterior interventricular artery
Middle cardiac vein.
What are the branches of the left coronary arteries
Left anterior descending
Left marginal artery
Left circumflex artery
What structures support the mitral and tricuspid valves
Chordae tendinae which are attached to the papillary muscles on the inferior surface of the ventricles
What are the branches of the right coronary arteries
Right marginal artery
In 80-85% branches to give posterior interventricular artery
Where does the coronary sinus drain into
Right atrium
What are the tributaries of the coronary sinus
Great cardiac vein
Small cardiac vein
Middle cardiac vein
Posterior cardiac vein
What structures are related to the right lung
Oesophagus
Heart
Inferior vena cava
Superior vena cava
Azygous vein
What structures are related to the left lung
Heart
Arch of aorta
Thoracic aorta
Oesophagus
What does the lung root contain
bronchus
pulmonary artery
two pulmonary veins
bronchial vessels
pulmonary plexus of nerves and lymphatic vessels
How does the drainage of the right and left bronchial veins differ
Right bronchial vein - drains into the azygos vein
Left bronchial vein - drains into the hemiazygos vein
What level does the horizontal fissure of the right lung run at
T4
What epithelium lines the trachea and bronchi
Ciliated pseudostratified columnar epithelium, interspersed by goblet cells
Which nerve provides sensory innervation of the trachea
Recurrent laryngeal nerve
What is the arterial supply of the trachea
Inferior thyroid artery
What is the left main bronchus related to
Aortic arch - passes inferiorly
Thoracic aorta - passes anteriorly
Oesophagus
Which nerve innervates the bronchi
Vagus nerve
Where are the 2 pleural recesses
Costodiaphragmatic – located between the costal pleurae and the diaphragmatic pleura
Costomediastinal – located between the costal pleurae and the mediastinal pleurae, behind the sternum.
What are the 3 peripheral attachments of the diaphragm
Lumbar vertebrae and arcuate ligaments
Costal cartilages of ribs 7 -10
Ribs 11 - 12
Xiphoid process of sternum
Where does the right crus of the diaphragm arise from
Arises from L1-L3 and their intervertebral discs
Where does the left crus of the diaphragm arise from
Arises from L1-L2 and their intervertebral discs.
What passes through the hiatus in the diaphragm at T8
IVC
Terminal branches of the right phrenic
What passes through the hiatus of the diaphragm at T10
Oeosphagus
Right and left vagus nerve
Oesophageal branches of the left gastric artery/vein
What passes through the hiatus of the diaphragm at T12
Aorta
Thoracic duct
Azygous vein
Which muscle is the primary muscle of inspiration
Diaphragm
What is the arterial supply of the diaphragm
Inferior phrenic artery
Describe the attachment of the intercostal muscles
Originate at the lower border of the first rib inserts into the superior aspect of the rib below
What is the innervation of the intercostal muscles
Intercostal nerves (T1-T11)
The internal intercostal muscles are continuous with which muscle of the abdominal wall
Internal oblique muscle
What are the 3 layers of muscles between the ribs
Intercostal muscles
Internal intercostal muscles
Innermost intercostals
Where does transversus thoracis attach
From the posterior surface of the inferior sternum to the internal surface of costal cartilages 2-6.
Which ribs are considered typical ribs
Ribs 3- 9
Which ribs are considered atypical ribs
Ribs 1,2, 10, 11, 12
What are the posterior articulations of the ribs
Costotransverse joint - between the tubercle of the rib and the transverse costal facet of the corresponding vertebrae
Costoverterbal joint - Between the head of the rib, superior costal facet of the corresponding vertebra, and the inferior costal facet of the vertebra above.
What are the anterior articulations of the ribs
Ribs 1-7 attach to the sternum
Ribs 8-10 attach to costal cartilage
Ribs 11 -12 do not have an anterior attachment
Which are the ‘free floating’ ribs
11 and 12
What are the 3 parts of the sternum
Manubrium
Body
Xiphoid process
The fossa at either side of the jugular notch of the manubrium articulate to form which joint
Sternoclavicular joint
The sternal angle marks the level of what ribs
CC of 2nd rib
The tip of the xiphoid process is found at which level
T10
In which part of the spine are the spinous processes of the vertebrae long and slanting
Thoracic spine
From superficial to deep what are the ligaments of the spine
Supraspinous ligament
Interspinal ligament
Ligamentum flavus
Posterior longitudinal ligament
Anterior longitudinal ligament
The superficial muscles of the back are associated with movements of what
Shoulders
The intermediate muscles of the back are associated with movements of what
Thoracic cage
The deep muscles of the back are associated with movements of what
Movements of the vertebral column
What are the superficial back muscles
Trapezius
Latissimus dorsi
Levator scapulae
Rhomaboid major and minor
What are the intermediate back muscles
Serratus posterior superior
Serratus posterior inferior
What is the function of serratus posterior superior and what innervates it
Elevates ribs 2-5
Intercostal nerves
What is the function of serratus posterior inferior and what innervates it
Depresses ribs 9-12
Intercostal nerves
What are the superficial deep back muscles
Splenius capitus
Splenius cervicis
What are the intermediate deep back muscles
Erector spinae
Iliocostalis
Longissimus
Spinalis
What are the 3 groups of the deep layer of the deep back muscles
semispinalis, multifidus and rotatores.
