Thorax Flashcards
What makes up the thoracic wall skeleton?
12 pairs of ribs and costal cartilages
12 thoracic vertebrae and intervertebral discs
Sternum
Ribs are classified as what type of bones and do they contain bone marrow?
Flat bones, and yes they have BM.
Name the parts of sternum
Manubrium, body, xiphoid process
Divide ribs into true, false and floating. What makes them fall into these categories?
1-7 true. Attached directly to sternum
8-10 false. Attached to the cartilage of the superior rib
11&12 floating. Not connected to sternum
Where can you find the costal groove of a rib and what is its function?
On the internal surface of a rib. Protects the costal nerve/vessels.
Name the parts of a typical rib and give main features of each
Head: has 2 facets for vertebra above and below it.
Neck: connects the head to the body at the level of tubercle
Tubercle: smooth, connects to transverse process
Body: thin, flat, curved
You are about to perform a thoracocentesis on a patient in the ER. Would you choose to insert the needle just above or below a rib and why?
Just above the rib to avoid the vessels that run just below a rib.
Name the atypical ribs
1,2,10,11,12
The shortest, broadest, most curved and almost horizontal rib.
What is the 1st rib
These ribs only have one facet on their heads.
1, 10-12
How many grooves run on superficial surface of the 1st rib and what is its/their function?
2
Subclavian vessels run here.
These ribs have no heads or tubercles
11 and 12
The first two ribs are the strongest and it takes a great amount of force to break them. You have a patient with a fracture of these ribs what do you suspect and what tests would you do?
The injury must be worse that it looks. Orders CXR, MRI, CT to check for internal injuries.
Characteristics of a thoracic vertebrae
Body, arch, 7 processes
BL costal facets
costal facets of transverse processes(except for inferior 2 or 3)
Long, inferior slanting spinous process
Sternal angle or angle of Loius significance
RAT PLANT
Rib 2*
Aortic arch*
Tracheal bifurcation*
Pulmonary trunk Ligamentum arteriosum Azygous vein enters SVC Nerve plexi (cardiac and pulmonary) Thoracic duct
Trapezoidal bone at level of T3-T4 with two BL clavicular notches
Manubrium
Flat elongated bone forming the anterior part of thoracic cage
Sternum
Bone on the anterior chest with costal notches
Body of sternum
Sword like shaped structure
Xiphoid process
Length of xiphoid is constant and never has a hole in it. T or F?
F
Inflamation of a rib or the cartilage connecting a rib.
Costochondritis
Name the thoracic apertures
Superior and inferior
Modified sweat glands on anterior surface of the chest
Breasts
Locate circular base of a breast
From lateral border of the sternum to midaxillary line.
What attaches breast to the skin?
Suspension ligament of Cooper
Define areola
Pigmented area around the nipple
Name the thoracic compartments
2 lateral - pulmonary
1 central - mediastinum
Accessory muscles of respiration
Pectoralis major/minor
Sarratus anterior
Scalenes
A fist in a balloon
What are pleurae (visceral and parietal)
Serous sack surrounding the lungs
Pleura
Differentiate btwn visceral and parietal pleura
Visceral - adherent to lungs, cannot be dissected form them
Parietal - adherent to thoracic wall, mediastinum and diaphragm
Define pleural sleeve
Area of continuity of visceral and parietal pleurae enclosing the root of the lung
4 parts of parietal pleura
Costal, mediastinal, diaphragmatic and cervical
Name the otential space btwn the 2 pleurae with capillary layer of serous fluid
Pleural space
What are costodiaphragmatic and costomediastinal recesses?
Potential spaces in pleural cavity at the respective junctions
Name the lines of pleural reflection and define each.
Sternal - where costal becomes continuous with mediastinal anteriorly
Costal- where costal becomes continuous with diaphragmatic
Vertebral- where costal becomes continuous with mediastinal posteriorly
Define lung root
Connects lung to trachea and heart. Formed by structures entering and leaving the lung at the hilum
How many lobes in each lung
Right - 3
Left - 2
Names and give the functions of lung fissures
Horizontal and oblique
Divide lung into lobes
Locate cardiac notch and lingula
Margin of the left lung
What is lingula?
Projection of the upper lobe of the Left lung
A blunt superior end of the lung ascending into root of neck
Apex of the lung
3 surfaces and 3 borders of the lungs
Costal, mediastinal and diaphragmatic surfaces
Anterior, posterior, inferior borders
Main bronchi pass from bifurcation of trachea to lung. T or F?
T
Left main bronchus is wider, shorter and more vertical than the right. T or F?
F. This is true about the right one.
What is carina?
A cartilaginous ridge within the trachea that runs antero-posteriorly between the two primary bronchi at the site of tracheal bifurcation
Pulmonary arteries raise from the pulmonary trunk at …..( hint: significant landmark)
Sternal angle.
Pulmonary arteries carry ‘venous blood’ and pulmonary veins carry ‘arterial blood’. T or F?
T
This compartment contains almost all thoracic viscera, extends from superior thoracic apertures to diaphragm, from sternum to vertebrae, and primarily consists of air or fluid filled structures.
Mediastinum (central)
Give location of Inferior mediastinum and into what parts it divides.
From sternal angle to diaphragm
Divided into anterior, middle and posterior
A part of mediastinum from superior thoracic aperture to sternal angle and the structures located here
Superior mediastinum: SVC Brachiocephalic vein Arch of aorta Thoracic duct Trachea Esophagus Thymus Vagus nerves Left recurrent laryngeal nerve* Phrenic nerve
Name the smallest subdivision of inferior mediastinum, give its location and it’s structures
Anterior mediastinum
From sternum to pericardium
Contains inferior part of thymus in kids
This part of inferior mediastinum contains the heart, pericardium, ascending aorta, pulmonary trunk, SVC, arch of azygous vein, main bronchi
Middle mediastinum
Locate the posterior mediastinum and name its structures.
Anterior to T5-T12. Thoracic aorta Thoracic duct Azygous and Hemizygous veins Esophagus and esophageal plexus Thoracic sympathetic trunks Thoracic splenic nerves
Double wall membrane enclosing the heart
Pericardium
What does the nerve supply to pericardium consist of.
Phrenic nerves, sympathetic trunks, vagus (X)
Cardiac cycle begins with diastole/systole and ends with diastole/systole.
Diastole( period of elongation and filling)
Systole ( shortening and emptying)
Thick layer of heart - cardiac muscle
Myocardium
Name the heart wall formed by visceral layer of pericardium
Epicardium
Heart layer covering the valves
Endocardium
Give location and orientation of the heart’s apex
Posterior to the left 5th intercostal space (9cm from median plane)
Directed anteriorly and to the left
Functions of fibrous rings in the heart
Keep valves open
Attachment for leaflets and cusps of valves
Attachment for myocardium
Electrical insulator between atria and ventricle
4 surfaces of the heart
Anterior, diaphragmatic, left and right pulmonary
Describe the base of the heart
Posterior aspect, formed by LA and slightly the RA.
Receives the pulmonary veins and SVC/IVC
Anterior surface of the heart is aka as____ and consists of?
Sternocostal
Mainly RV
Left pulmonary surface of the heart is made up of?
Mainly LV and forms cardiac impression of left lung
Diaphragmatic surface of the heart is aka as ____ and consists of?
Inferior
LV and partially RV
Right pulmonary surface of the heart is made up of?
Mainly RV
What and where is the coronary sinus?
Collection of veins delivering blood from coronary circulation to RA. Located on posterior inferior surface of the heart, medial to IVC
Obliquely placed partition btwn R and L ventricles. What structure, pertaining to electricity, runs through it.
Intraventricular septum
Right bundle of AV node
What is right auricle and its function?
Clonical pouch shaped projection on RA, increases its capacity
Give location of bi/tricuspid valves.
Tricuspid right heart
Bicuspid (mitral) left heart
Tri (3) right lung has 3 lobes
Bi (2) left lung has 2 lobes
What is conus arteriosus?
Conical pouch formed from upper RV that leads to pulmonary trunk. (cone)
Wall of the RA is slightly thicker than the one of LA. T or F?
False. It’s the opposite
Wall of the LV is 4-5 times thicker than the wall of RV. T or F?
F. 2-3 times
What vessels supply the myocardium and where do they arise from?
Coronary arteries
Right and left arise from aortic sinuses at proximal part of ascending aorta just above the aortic valve
This artery supplies RA, most of RV, part of LV, part of IV septum, SA node (60%), AV node (80%)
RCA
This artery arises from coronary sinus, runs in coronary sulcus, supplies the SA node, gives a right marginal branch.
RCA
This artery divides into LAD and circumflex.
LCA
This artery runs to the apex of the heart, then swings posteriorly to anastomoses with posterior IV branch of RCA.
LAD
This artery supplies LA, most of LV, part of RV, most of IV septum (ant2/3), SA node.
LAD
This structure initiates and regulates the impulses and is located at junction of SVC and RA
SA node
Small collection of nodal tissue in posteroinferior region of Intra atrial septum near coronary sinus
AV node
Name sequence of conducting system
SA nodes initiates impulse
Impulse reaches AV
Signal spread from AV node through AV bundle into R/L bundle bunches
Signal reaches purkinje fibers
What are purkinje fibers?
Right and left bundle branches of AV bundle travel along the IV septum and then into subendocardial branches called purkinje fibers.
Lymphoid organ in anterior chest, rich in blood supply undergoes involution after puberty.
Thymus
This great vessel is formed by union of internal jugular vein and subclavian veins.
Bravhiocephalic vein
Brachiocephalic veins merge to form …..
SVC
Left brachiocephalic is twice as long as the right one. T/F?
T
Left brachiocephalic vein receives lymph from thoracic duct. T/F?
T. Right gets it from right lymphatic duct
Returns blood from all structures superior to diaphragm except lungs and heart , ends at 3rd costal cartilage where it enters the RA.
What is SVC
Location of right phrenic nerve
Between SVC and mediastinal pleura
Which side of the vertebral column does the descending aorta run?
Left
What’s the correlation between Ligamentum arteriosum and antibiotics in pregnancy.
May close prematurely (normally close shortly after birth) if antibiotics are taken in third trimester.
What is Ligamentum arteriosum?
A small ligament (remnant of fetal ductus arteriosus) attached to superior surface of the left pulmonary artery and the proximal descending aorta.
Name the branch of the aortic arch that is largest, anterior to trachea , posterior to left brachiocephalic vein, and what does it divide into?
Brachiocephalic trunk. Divides into mom on carotid and right subclavian arteries.
Second branch of aortic arch, posterior to Manubrium, ascends anteriorly to left subclavian artery.
Left common carotid artery
Branch of the aortic arch arising from posterior part, has no branches in mediastinum, as it leaves the thorax it passes posterior to left sternoclavicular joint and lateral to left common carotid.
Left subclavian artery
Position of vagus nerve in relation to common carotid arteries.
Lies posterolaterally to the arteries.
Vagus (x) nerve arises from which part of the brain?
Medulla
Describe the position of the right vagus nerve as it enters the thorax in relation to subclavian artery and what it gives rise to.
It runs anterior to subclavian artery and gives off the right recurrent laryngeal nerve.
Describe the position of the left vagus nerve as it enters the thorax in relation to adjunct arteries and what it gives rise to.
Enters thorax between left common carotid and left subclavian arteries and posterior to left brachiocephalic vein. It gives of the left recurrent laryngeal nerve.
The only motor supply to diaphragm.
Phrenic nerves
Location of trachea in relation to esophagus and where does it end?
Anterior to esophagus. Ends at sternal angle
Trachea does not incline right or left as it descent. T/F?
F. Inclines to the right a little.
Cartilaginous rings encircle the trachea completely. T/F?
F. Posterior surface is flat, rings incomplete.
Esophagus initially inclines to the left as it descends. What moves it back to median plane?
Aortic arch
Fibrousmuscular tube extending from pharynx to the stomach
Esophagus
Location of thoracic aorta
Posterior mediastinum
On the left side of T5-T12
Posterior to root of the lung, pericardium and esophagus.
Locate azygous vein
Descents on right side of aorta and accompanies it through aortic hiatus of diaphragm.
Esophagus is compressed in three places. Name them*
Aortic arch, left main bronchus, diaphragm
where does the 2nd rib attach anteriorly?
btwn manubrium and the body at sternal angle
