Thorax Flashcards
Which structure separates the subclavian artery and vein?
Scalenus anterior muscle
Where is the mitral valve best auscultated?
Over the cardiac apex
What is the blood supply to the superior 1/3rd of the oesophagus?
Inferior thyroid artery
What is the blood supply to the middle 2/3rds of the oesophagus?
Direct branches from the thoracic aorta
What is the blood supply to the lower 1/3 of the oesophagus?
Oesophageal branches off the left gastric artery
What is the level of the sternal angle? (angle of louis)
T4, or in line with rib 2
Which ribs are your false ribs?
8-12
Which ribs are your floating ribs?
11 and 12
Which ribs are your true ribs?
1-7
What are the three parts of the sternum?
Manubrium, body, xiphoid process
How far above the clavicle does the cervical pleura project?
3cm
How low down does the pleura extend to?
Mid-clavicular line: rib 8
Mid axillary line: rib 10
Scapular line: rib 12
What are the four parts of the pleura?
Diaphragmatic, costal, mediastinal, cervical
What is the costodiaphragmatic recess?
The potential space between the lung and the pleura at the most inferior part of the lung
What are the costomediastinal recesses?
Potential spaces around the mediastinum
Where is the apex of the heart?
5th intercostal space, left mid-clavicular line
Where is the inferior border of the heart?
Upper border of the 6th costal cartilage, 1cm laterally from the edge of the sternum to the apex
How many intercostal nerves are there?
11
What is the 12th thoracic nerve called?
Subcostal nerve
What are the two branches of the intercostal nerves?
Lateral and anterior cutaneous branches
What is the action of pectoralis major?
Adduction, flexion, extension and internal rotation
What is the innervation to Pectoralis major?
Lateral and medial pectoral nerves (C5-T1)
What is the insertion of pec major?
Crest of the greater tubercle of the humerus - lateral lip of the intertubercular sulcus
What are the origins of pec major?
- medial half of the clavicle
- anterior surface of the sternum
- Costal cartilages of ribs 1-6
- Anterior layer of the rectus sheath
What are the two heads of pectoralis major?
Sternocostal head and clavicular head
What are the borders of the deltopectoral triangle?
Clavicle superiorly, lateral border of pec major medically, and medial border of deltoid laterally
What is the clinical significance of the deltopectoral triangle?
It contains the cephalic vein, and the deltoid branch of the thoracoacromial artery
What lies within the deltopectoral groove?
The cephalic vein
What does the cephalic vein empty into?
The axillary vein
Which part of the upper limb does the cephalic vein drain?
The radial aspect of the arm, forearm and hand
Which of the pectoral nerves is deeper?
The medial pectoral nerve is deeper than the lateral
Where do the medial and lateral pectoral nerves come from?
Brachial plexus, they emerge from under the clavicle
What are the attachments of pectoralis minor?
Insertion: Coracoid process of the scapula
Origin: ribs 3-5
What is the innervation to pec minor?
Medial pectoral nerve
What is the function of pectoralis minor?
Protraction of the scapula, stabilization of the scapula
What are the attachments of the subclavius muscle?
O: Costal cartilage and sternal end of rib 1
I: Anteroinferior surface of middle 1/3rd of the clavicle
What is the action of the external intercostals?
Elevate the ribs during forced inspiration
What is the blood supply the intercostal muscles?
Intercostal artery (vein drains and intercostal nerve innervates)
What is the action of the internal and innermost intercostals?
Depress ribs during forced expiration
Between which layers of intercostal muscles do the neurovascular bundles lie?
Between the internal and innermost intercostals
What are the attachments of serratus anterior?
Origin: Ribs 1-9/10
Insertion: Anterior surface of the scapula
What are the attachments of transversus thoracis?
O: Inferior surface of the sternum and xiphoid process
I: Internal surface of ribs 2-6
What is the action of transversus thoracis?
Depresses ribs during expiration
What is the innervation to transversus thoracis?
Intercostal nerves
What is the innervation to serratus anterior?
SALT (Serratus anterior, Long thoracic nerve) (C5,6,7 raise your arms to heaven)
What is the action of serratus anterior?
Protraction of the scapula
Which artery does the internal thoracic (internal mammary) artery come off?
The subclavian artery
Which artery does the superior epigastric artery come off?
The internal thoracic artery
Where does the internal thoracic artery run?
Deep and lateral to the sternum
What do the internal thoracic (internal mammary) veins drain into?
The brachiocephalic veins
Where does the subclavian artery lie in relation to the brachiocephalic vein?
Superior and more deep
Where are the parasternal lymph nodes?
Either side of the body of the sternum, deep to the intercostal muscles
What are the nerve roots of the phrenic nerve?
C3,4,5 - Keeps the diaphragm alive
Where do the intercostal VAN lie?
In the subcostal groove, VAN from superior to inferior.
What is the path of the phrenic nerves to the diaphragm?
Runs anterior to subclavian artery, anterior to hilum of lung, passes over fibrous pericardium
Where do the phrenic nerves pass through the diaphragm?
Left: straight through at apex of heart
Right: Through the caval hiatus
Which vascular structures run alongside the phrenic nerve?
The pericardiophrenic artery and vein
What is the pulmonary ligament?
A triangular fold of pleura that extends from the hilum of the lung to the mediastinum. A double fold of mediastinal pleura.
What is the function of the pulmonary ligament?
It allows vascular enlargement of the hilar vessels in times of increased cardiac output
How many lobes do the lungs have?
Left: 2
Right: 3
Where does the oblique fissure lie in relation to the ribs?
From rib 5 posteriorly to rib 6 anteriorly
Where does the horizonal fissure lie in relation to the ribs?
Along the intercostal space below rib 4
What is the pathway of the right vagus nerve?
Passes between the brachiocephalic vein and brachiocephalic trunk, descends alongside trachea, to oesphagus
What branches does the right vagus nerve give off in the thorax?
Branches to the cardiac and pulmonary plexus
What branch does the left vagus nerve give off in the thorax?
Left recurrent laryngeal nerve
What is the path of the left recurrent laryngeal nerve?
Branches off the vagus at the aortic arch, runs posteriorly under the arch and back up towards the larynx
What is the path of the right recurrent laryngeal nerve?
It branches off the right vagus at the subclavian artery, loops posteriorly under the subclavian and ascends medially towards the larynx
What is the path of the left vagus nerve?
Passes between left common carotid and brachiocephalic vein, passes over the aorta giving off the L recurrent laryngeal nerve
What impressions are found on the left lung?
Cardiac impression, groove for arch of aorta, groove for subclavian artery, oesophagus
What impressions are found on the right lung?
Groove for azygous vein, groove for SVC, groove for oesophagus, cardiac impression
Where do the arteries and veins of the hilum of the lung lie in relation to each other?
Veins are usually inferior
What are the branches of the bronchial tree?
Trachea - lobar bronchi - segmental bronchi - subsegmental bronchi - conducting bronchioles - terminal bronchioles - respiratory bronchioles
Which arteries supply the lung tissue with oxygen?
The bronchial arteries
How many costal facets do the ribs have?
One except ribs 2 and 7 which have 2 demi-facets
Where is the aortic valve best heard?
2nd intercostal space, 1cm R of sternum
Where is the pulmonary valve best heard?
2nd intercostal space, 1cm L of sternum
Where is the Tricuspid valve best heard?
5th intercostal space, 1cm L of sternum
Where is the mitral valve best heard?
5th intercostal space, mid-clavicular line
What is the mnemonic to remember the valve placement?
All Prostitutes Take Money
What does the superior articular process of the vertebrae articulate with?
The inferior articular process of the vertebra above
What are the parts of the intervertebral disc called?
Annulus fibrosus, nucleus pulposus
What are the distinguishing characteristics of a cervical vertebra?
Small, kidney-bean-shaped body, no costal facets, transverse foramina, bifid spinous process (except C1 and maybe C7)
What runs through the transverse foramina?
The vertebral arteries
Which cervical vertebra has no spinous process?
C1 - atlas
Which vertebra has an odontoid peg?
C2 - axis
What are the distinguishing characteristics of a thoracic vertebra?
Demi-facets (costal facets) for rib articulation, long posteriorly facing spinous processes, circular vertebral foramen
What are the distinguishing characteristics of the lumbar vertebrae?
Large, triangular vertebral foramen, short stumpy spinous process
How many vertebrae are in the sacrum?
5
How many vertebrae are in the coccyx?
4
Where do the bronchial arteries come from?
Direct branches from the thoracic aorta
What are the branches that come off the internal thoracic artery?
Pericardiophrenic, anterior intercostals, superior epigastric, musculophrenic, phrenic
What are the four main groups of branches that come off the thoracic aorta?
Pericardial, eosophageal, bronchial, posterior intercostal
At what vertebral level is the carina?
T4
Which bronchus is more vertically disposed?
The right
Where does the azygous vein drain into?
SVC, around T4
Where do the oesophagus, and trachea lie in relation to each other?
Oesophagus is most posterior and to the left, the trachea lies anteriorly to the oesophagus
Where do the para-sternal lymph-nodes drain into?
The thoracic duct
What is the cisterna chyli?
A dilated sac at the lower end of the thoracic duct that collects lymph from the abdomen and lower limbs
Where does the thoracic duct lie?
To the left of the oesophagus
Where do the azygous and hemi-azygous veins run?
Azygous runs along the right of the vertebral body, the hemi-azygous runs along the left
What is the accessory hemi-azygous vein?
A vein that runs superior to the hemi-azygous vein and drains into the azygous vein
What goes through the three main diaphragmatic hiati?
T8: Vena Cava + phrenic
T10: Oesophagus + vagus + gastric arteries
T12: Aorta + thoracic duct + azygous vein
The sympathetic trunk comes from which spinal levels?
T1-L2
Which ganglia contribute to the greater splanchnic nerve?
5-9
Which ganglia contribute to the lesser splanchnic nerve?
10-11
Which ganglia contribute to the least splanchnic nerve?
12
What does the greater splanchnic nerve innervate?
Foregut
What does the lesser splanchnic nerve innervate?
Midgut
What does the least splanchnic nerve innervate?
Kidneys
Which muscles are involved in forced expiration?
Transversus thoracis, internal + innermost intercostals, serratus posterior inferior, diaphragm, external obliques, rectus abdominis, transversus abdominis
Which muscles are involved in forced inspiration?
Sternocleidomastoid, scalenes, serratus posterior superior, pec minor, erector spinae, external intercostals
What is the epithelium of the trachea?
Psuedostratified ciliated columnar
How many bronchial arteries are there?
3 per lung, directly from thoracic aorta
Which nerve innervates sternocleidomastoid?
Accessory nerve
Which nerves roots form the pulmonary plexus?
T2-T5
What are the boundaries of the visceral pleura on rib levels?
Midclavicular line = 6th rib
Midaxillary line =8th rib
Scapular line = 10th rib
Where are the positions of the pulmonary arteries in relation to the bronchii?
RALS
Right artery is anterior to bronchus
Left artery is superior to bronchus
What is the function of the papillary muscles?
To prevent prolapse of the atrioventricular valves. They open and close passively due to changes in pressure
Where do the posterior intercostal arteries come from?
Direct branches of thoracic aorta and subclavian artery (for some of the superior intercostal arteries)
What structures empty into the SVC?
Left and right brachiocephalic veins and azygous vein
Lymph from the right upper quadrant of the body drains into venous circulation via what?
The right lymphatic duct
What structure is found posterior to the right main bronchus?
The azygous vein
