Thorax Flashcards
1
Q
What are the two joints connecting the ribs to the vertebral column and what is the overall name
A
Costovertebral joints: Joints of the heads of the ribs and by the tubercles - the costotransverse joints.
2
Q
What are the anterior joints of the ribs
A
Upper 7: articulate with the sternum at the sternocostal joints.
Next 3: articulate with each other
Last 2: Free ribs
3
Q
Describe the joints of the heads of the ribs
A
Two articular facets with a ridge in between.
The lower one with its own vertebra, upper one with the vertebra above.
Attached to the ridge between the two and the body of the vertebra above is the intra-articular ligament. The radiate ligament consists of three bands: upper passes across the joint to the body of the vertebra above, the central horizontally and the deep to the anterior longitudinal ligament.
4
Q
What are the exceptions to the rule for the joints of the heads of the ribs
A
The first rib articulates with the T1 vertebra only.
the last two ribs only articulate with their own vertebrae. In these instances the radiate ligament consists of two bands (not three).
5
Q
Describe the costotransverse ligament
A
3 ligaments: costotransverse, lateral costotransverse, superior costotransverse.
6
Q
Describe the costochondral joints
A
Primary cartilaginous joint that each rib makes with its costal cartilage
7
Q
What type of joint are interchondral joints and which ribs are involved with these
A
The costal cartilages of 6 and 7, 7 and 8, 8 and 9 are joined to parts of adjacent surfaces of each other by small synovial joints.
8
Q
Why is the first sternocostal joint different from the others
A
First costal cartilage articulates with the manubriaum by a primary cartilaginous joint, allowing no movement
9
Q
What type of joint is the sternocostal joint of ribs 2-7
A
Synovial joint
10
Q
Describe the manubriosternal joint
A
Surfaces are covered by a hyaline cartilage with an intervening disc of fibrocartilage.
11
Q
How many layers of thoracic muscles are there?
A
3
- outer
- middle
- inner
12
Q
What is serratus posterior superior
A
Outer layer muscle of the thoracic wall. Arises from the spinous processes of the lower two cervical and the upper two thoracic vertebrae. Slopes down and is inserted into the angles of ribs 2-5
13
Q
What runs on the anterior surface of serratus posterior superior
A
Dorsal scapular nerve and vessels
14
Q
What is serratus posterior inferior
A
Arises from the lower two thoracic and upper two lumbar spinous processes. Inserted just lateral to the angles of the lowest four ribs
15
Q
What distinguishes the levator costae muscls
A
They are the only thoracic muscles to be supplied by the posterior rami of spinal nerves (C8-T11). 12 pairs of fan shaped muscles from the tip of a transverse process and inserted into the upper border of the rib below, lateral to its tubercle.
16
Q
What way do the fibres of the external intercostals go
A
Obliquely downwards and forwards.
17
Q
What happens to the fibres of the external intercostals at the costochondral junction.
A
It is replaced by the anterior intercostal membrane which extends to the side of the sternum.
18
Q
What is the middle layer of thoracic musculature
A
Internal intercostal muscles. Fibres run downwards and backwards and extend to the sternum. At the back it is replaced by the posterior intercostal membrane. This extends from the angle of the rib to the superior costotransverse ligament at the posterior limit of the space
19
Q
How many muscles in the inner layer of thoracic wall
A
3
- innermost intercostal
- Transversus thoracis: arise from the lower end of the sternum (and are anterior)
- Subcostal muscles: posterior
20
Q
What is the order of the neuromuscular bundle in the intercostal spaces
A
Above to downwards: vein, artery , nerve. It runs in the plane between the internal intercostal and innermost intercostal. They are protected by the downward projection of the lower border of the rib.
21
Q
What artery supplies the upper 2 posterior spaces
A
Superior intercostal artery - a branch of the costocervical trunk, origin is the second part of the subclavian artery (behind scalenus anterior)
22
Q
What supplies the remaining 9 posterior intercostal spaces
A
Posterior intercostals - separate branches fo the descending thoracic aorta.
23
Q
What vessel supplies the upper 6 spaces anteriorly
A
The internal thoracic artery
24
Q
What vessel supplies the lower 7th, 8th and 9th spaces
A
Musculophrenic artery - gives off two anterior intercostal arteries that pass backwards to make end-to-end anastomosis with the posterior vessels
25
What vessel supplies the last 2 ribs
There are no anterior intercostal arteries in the last two spaces.
26
Venous drainage of the anterior intercostal space
2x anterior intercostal veins that drain into the musculophrenic and internal thoracic veins
27
Venous drainage of the posterior lower 8 spaces
One posterior vein that drains into the azygos vein on thee right and the hemiazygos and accessory hemiazygos on the left.
28
Venous drainage of the 1st posterior intercostal space
Supreme intercostal vein - this drains into either the vertebral vein or the brachiocephalic vein of its own side.
29
Venous drainage of the 2nd and 3rd posterior intercostal space
Collected into a single trunk on each side - the superior intercostal vein.
30
Drainage of the superior intercostal vein on the righ
Azygos vein
31
Drainage of the superior intercostal vein on the left
Forward over the arch of the aorta, superficial to the vagus nerve and DEEP to the phrenic nerve, to empty into the left brachiocephalic vein.
32
How does the internal thoracic artery supply the anterior body wall from the clavicle to the umbilicus
Anterior intercostal arteries. Divides into the superior epigastric and musculophrenic arteries.
33
Venous drainage of the internal thoracic
Internal thoracic artery is accompanied by two venal comitantes that empty into the brachiocephalic vein.
34
Anterior attachment of the suprapleural membrane
Inner border of the first rib and costal cartilage
35
Posterior attachment of the supra pleural membrane
Tranverse process of C7 vertebra.
36
What muscle can be found in the posterior attachment of the sub pleural membrane
Scalenus minimus
37
Embryology of the diaphragm: what layer of muscles does iit originate from
The inner layer (transverses)
38
Which dome of the diaphragm is higher and what levels do the right and left reach
Right: 4th space (nipple)
Left: 5th space
Central tendon: level with the xiphisternal joint
39
What is the right crus
Largest of the crura. Attached to the upper three lumbar vertebrae. Some of the right crus fibres slope to the left surrounding the oesophageal orrifice in a sling-like loop.
40
Attachment of the left crus
upper two lumbar vertebrae and disc.
41
What level is the median arculate ligament
T12
42
What is the medial arcuate ligament
Thickening in the psoas fascia extending from the lower part of the body of L1 to a ridge on the anterior surface of the transverse process of L1
43
What is the lateral arcuate ligament
Extends across to the 12th rib at the lateral. border of quadrates lumborum. (transverse process of L1 tot he 12th rib).
44
What structure is the central tendon of the diaphragm attached to
The fibrous pericardium.
45
What structure pierces the central tendon
The vena cava
46
Location of the aortic opening in the diaphragm and what it transmits
T12 vertebra.
Midline arch between the overlapping right and left crural fibres, behind the diaphragm.
Transmits the aorta with the azygos to the right and the thoracic duct leading up from the cisterns chyli.
47
Location of the oesophageal opening and what it transmits
Opposite T10 vertebra
Usually slightly to the left of the midline and behind the seventh costal cartilage.
Lies in the fibres of the left crus but a sling of fibres from the right passes over it to loop around it
It transmits the oesophagus along with the oesophageal branches of the left gastric artery, accompanying veins and lymphatics.
48
What attaches the oesophagus to the oesophageal opening
The phreno-oesophageal ligament
| - this is stretched in the 'sliding' type of hiatus hernia.
49
Location of the vena caval foramen and what it transmits
Opposite the T8 vertebra to the right of the midline behind the sixth right costal cartilage.
50
What pierces the diaphragm at the same level as the vena caval foramen
right phrenic nerve
51
What are the smaller structures that pierce the diaphragm.
Hemiazygos vein - left crus
Greater, lesser and least splanchnic nerves pierce each crus.
Sympathetic trunk- medial arcuate ligament.
52
Blood supply of the diaphragm
Costal margin - supplied by the lower five intercostal and subcostal arteries.
The main area supplied by the right and left inferior phrenic arteries from the abdominal aorta.
53
Nerve supply of the diaphragm
Each half is supplied by its own phrenic nerve nerve. The part of the right crus that lies to the left of the oesophageal opening is supplied by the left phrenic.
The lower intercostal nerves send some proprioceptive fibres to the periphery of the diaphragm but no motor fibres.
54
Where do the right and left phrenics pierce the diaphragm
Right - passes through the foramen for the inferior vena cava.
Left pierces the muscular part in fromt of the central tendon.
55
Why is there more dead space on the right side of the superior mediastinum
Right side of the superior mediastinum = veins. Veins expand during increased blood flow.
56
Boudaries of the superior mediastinum
Manubrium. Posterior boundary = bodies of first four thoracic vertebrae.
57
Contents of the superior mediastinum
```
Arch of the aorta
Brachiocephalic trunk
Trachea
Left vagus and apex left lung.
Right and left brachiocephalic veins
```
58
What differs in the course of the vagus nerve on the left sup. mediastinum compared with right.
Great arteries keep the left vagus and apex of the left lung away from contact with the trachea.
59
Describe the arch of the aorta in the superior mediastinum
at the manubriosternal joint the ascending aorta becomes the arch which passes OVER the left bronchus to reach the body of T4 to the left of the midline.
60
What crosses the arch of the aorta
Left phrenic and left vagus.
Left recurrent laryngeal hooks around the ligament arteriosum to pass upwards on the right side of the arch, in the groove between the trachea and oesophagus.
61
What is contained in the adventitial layer of the arch of the aorta
baroreceptors - innervated by vagal fibres which pass to the nucleus of the tracts solitarius.
62
What lies under the arch of the aorta.
Aortic bodies - detect hypoxia and are involved in respiratory refexes
63
What lies in front of the brachiocephalic artery
The termination of the left brachiocephalic vein
64
What is the branch of the brachiocephalic artery in sup. mediastinum
Thyroidea ima artery. rare. may originate from the arch of the aorta
65
Course of the left subclavian artery in the sup. mediastinum
Arises behind the left common carotid then arches over the left lung apex (which it grooves).
66
What is the ligamentum arteriosum
It's the shrivelled fibrous remnant of the ductus arteriosus.
67
Origin and insertion of ligament arteriosum
Commencement of the left pulmonary artery to the aortic arch.
68
What is closely associated with the ligamentum arteriosum
Left recurrent laryngeal nerve hooks around it. Superficial part of the cardiac plexus lies anterior to it. Deep part is on its right, in front of the left main bronchus.
69
Location of the formation of the brachiocephalic vein
Confluance of the internal jugular vein an subclavian vein medial to scalenus anterior and in front of the first part of the subclavian artery.
70
Tributaries to brachiocephalic vein
```
Those corresponding to the first part of the subclavian artery
- Vertebral
- Inferior thyroid
- Internal thoracic
Left side: superior intercostal
```
71
Left brachiocephalic vein - tributaries and relations.
Commencement receives the thoracic duct.
Receives the left superior intercostall vein, thymic vein.
Thyrmus and pretrachial fascia lie in front.
72
What is vulnerable to damage in a suprasternal incision (tracheotomy)
Left subclavian
73
SVC landmarks
lower border of the first right costal cartilage to the second costal cartilage (where it pierces the pericardium) to the third costal cartilage (where it enters the right atrium).
74
What happens to the SVC behind the sternal angle
Receives the azygos vein
75
What are the three parts to the cardiac plexus
Coronary branch, cardiac part, pulmonary part.
76
What forms the superficial part of the cardiac plexus
Union of the inferior cervical cardiac branch of the left vagus and the cardiac branch of the left cervical sympathetic gangion
77
Where is the superficial part of the cardiac plexus based
Lies in front of the ligamentum arteriosum and becomes continuous with the deep part
78
What contributes to the deep part of the cardiac plexus
Right vagus nerve (upper and lower cervical branches) Left vagus, branch of each recurrent laryngeal nerve, sympathetic fibres from the 5 cervical sympathetic ganglia.
79
Landmarks of the trachea
Commences at C6 - 5cm above the jugular notch. Bifurcates just below the lower border of the manubriam.
It is 10cm long and 2cm in diameter.
80
Blood supply of the trachea
Branches from the inferior thyroid and bronchial arteries form anastomotic networks in the tracheal wall. Veins drain to the inferior thyroid plexus.
81
Right phrenic nerve course
In contact with right brachiocephalic, SVC, Right atrium, IVC on medial side. Passes through the vena caval foramen in the central tendon.
82
Left phrenic nerve course
lateral to the left common carotid and left subclavian arteries. it crosses the arch of the aorta LATERAL to the superior intercostal vein, in front of the vagus nerve. It then passes through diaphragmatic muscle.
83
What differs in the course of the right vagus vs left vagus
Left is "held away" from the trachea by the great arteries. It passes over the arch of the aorta deep to the left superior intercostal vein.
84
What happens to each vagus nerve as it reaches the oesophagus.
The nerves ever the midline over the oesophagus in a plexus over the lower aspect. They become mixed.
85
What vessel does the fibrous pericardium NOT fuse with
Inferior vena cava
86
What is the fibrous pericardium derived from
Septum transverses (as is the central tendon).
87
What connects the fibrous pericardium to the sternum
Upper and lower ends are connected by weak sternopericardial ligaments
88
What is the transverse sinus
The transverse sinus is a communication from right to left and dorsal to the heart tube, between its arterial and venous ends.
89
If you put your finger in the transverse sinus, what would you be touching
Behind the aorta and pulmonary trunk
| In front of the SVC on the right and left auricle on the left.
90
What is the oblique sinus
It is a cul-de-sac between the two left and right pulmonary veins and the inferior vena cava. Its anterior wall is formed by the posterior wall of the left atrium.
91
Nerve supply of the fibrous pericardium
Phrenic nerve
92
Nerve supply of the visceral pericardium
Insensate - the pain from the heart originates in the muscle or the vessels and is transmitted by sympathetic nerves.
93
Describe a pericardial drainage
Needle inserted in the angle between xiphoid and left 7th costal cartilage a the costal margin and directed upwards and slightly medially through the central tendon of the diaphragm into the pericardial cavity
94
Right border of the heart
Right atrium
95
Inferior border of the heart
Right ventricle
96
Apex of the heart
Left ventricle
97
Left border of the heart
Left ventricle
98
Anterior/sternocostal surface
Right atrium, vertical atrioventricular groove and right ventricle.
99
Inferior/ diaphragmatic surace
Right atrium
100
Posterior surface/ base of the heart
Left atrium
101
Surface markings of the heart
Right border= right third costal cartilage to lower border of right 6th costal cartilage. Inferior border = right sixth costal cartilage to the apex. Apex Is the left 5th intercostal space.
102
What occupies the lower end of the RA
Orifice for the IVC
103
What is located at the upper end of the RA
Right auricle, overlying the commencement of the aorta
104
What is the sulcus terminalis
It is produced by the projection into the right atrial cavity of a vertical ridge of heart muscle, crista terminalis.
105
What happens to the interior of the right atrium to the right of the crista terminalis
It becomes projected into a series of horizontal ridges called the pectinate muscles.
106
What does the rough area to the right of the crista terminalis represent
The true auricular chamber of the embryonic heart. The remainder of the atrial cavity is produced by the right horn of the sinus venosus
107
What opens into the right atrium above the septal cusp of the tricuspid valve.
Coronary sinus
108
What is the shallow depression in the interatrial septum
Fossa ovalis.
109
What is the fossa ovalis
Primary septum of the fatal heart. Located in the lower part of the septum
110
What is the upper margin of the interatrial septum and what does it represent
Limbus - lower edge of the secondary septum
111
What is a persistent foramen ovale
Failure of fusion of the two septa
112
What is the atrioventricular groove
Vertical over the front of the heart and anteroposterior on the inferior surface
113
What lies in the atrioventricular groove
Right coronary artery, fat.
114
What is the trabeculae carnae
It is the muscular ridges and bundles that line the interior of the right ventricle.
115
What is the septomarginal trabecula
ridges of trabeculae carnage that has broken free and lies in the cavity attached to the interventricular septum and the anterior papillary muscle.
116
What does the septomarginal trabecula contain
Part of the right branch of the conducting bundle.
117
What are the papillary muscles
Part of the trabeculae carnae broken free and attaching to the cusps of the tricuspid valve
118
What are the cusps of the tricuspid valve
Anterior, posterior and septal.
119
What are the chordae tendinaeae
Inelastic cords which diverge from the papillary muscles and prevent the cusps being everted when the ventricle contracts.
120
What are the valves of the pulmonary valve
Semilunar cusps - anterior, left and right.
121
Which valve is higher - aortic or pulmonary
Pulmonary
122
What enters the left atrium
four pulmonary veins enter it symmetrically
123
What are the mitral valve cusps
Anterior and posterior cuspss.
124
Describe the papillary muscles of the left ventricles
Anterior and posterior - anterior is largest. Both are connected by chordae tendinae to each valve cusp.
125
What are the cusps of the aortic valve
Right left and posterior.
126
Branches of the ascending aorta
Right and left coronary from the the coronary sinuses
127
What does the ascending aorta spiral with
the pulmonary trunk
128
Where does the pulmonary trunk divide
Emerges from the fibrous pericardium, divides in the concavity of the aortic arch and in front of the left main bronchus.
129
Where does the SA node lie
It is a crescent shaped mass of tissue in the right atrium just below the SVC near the top of the crista terminalis.
130
What cells are contained in the SA node.
Pacemaker or P cells - generate the impulses for contraction.
131
Where does the AV node lie
Buried in the muscle of the interatrial septum above and to the left of the opening of the coronary sinus - deep to "Koch's triangle".
132
First branch of the right coronary
Conus artery
133
What does the SA nodal artery supply
The SA node in 60% of hearts.
134
What does the left coronary branch in to
Circumflex - continues down to the back of the heart in the atrioventricular groove, giving off its various ventricular branches and anastomoses with the end of the right coronary.
135
Which artery is most commonly affected by disease
Anterior interventricular artery (or Left anterior descending)
136
Which artery lies in the interventricular groove
Left anterior descending/ anterior interventricular
137
What are the veins of the heart
Venae cordis minima e, anterior cardiac, coronary sinus with 5 tributaries - great, middle antd small vein, posterior vein and oblique vein
138
Where does the coronary sinus lie
In the posterior part of the atrioventricular groove.
139
Where does the coronary sinus commence
Alongside the entrance of the oblique vein of the left atrium.
140
Where does the middle cardiac drain to
It accompanies the posterior interventricular artery and opens near the termination of the coronary sinus
141
Where do the anterior cardiac veins run to
They drain independently into the right atrium
142
Where do the vena cords minimae drain to
Small veins in the walls of all four chambers of the heart that open directly into the respective chambers.
143
Where does the lymphatics of the heart drain to
Aorta and pulmonary trunk and empty into the tracheobronchial lymph nodes and mediastinal lymph trunks
144
Bordesrs of the descending aorta
T4 vertebra to the T12 vertebra.
145
Branches of the descending aorta
9 posterior intercostal arteries on each side, subcostal artery, bronchial arteries and some small oesophageal vessels
146
What crosses the oesophagus in the superior mediastinum
Crossed by the arch of the aorta on the left side and azygos on its right.
147
What crosses the oesophagus in the posterior mediastinum
The left main bronchus and the right pulmonary artery
148
What are the constrictions of the oesophagus
Cricopharyngeal sphincter, Aortic arch at 22cm, Left main bronchus at 27cm, Where it passes through the diaphragm at 38cm.
149
What vessel supplies the upper oesophagus and what is the venous drainage
the inferior thyroid arteries. Drains to the brachiocephalic veins
150
What supplies the middle oesophagus and what is the venous drainage
Oesophageal branches from the aorta, drainage to the azygos veins
151
What supplies the lower part of the oesophagus and venous drainage
The left gastric artery, drains to the portal vein.
152
Why do oesophageal varices arise
Because the lower oesophagus drains to the portal vein, there is a anastomosis between the portal and systemic venous systems.
153
What level is the portal-systemic anastomosis of the oesophagus
T8 vertebra.
154
Nerve supply of the upper oesophagus
Recurrent laryngeal nerve and sympathetic fibres from cell bodies in the middle cervical ganglion running in on the inferior thyroid arteries.
155
Nerve supply of the lower oesophagus
Sympathetic trunks and greater splanchnic nerves.
156
Parasympathetic supply of the oesophagus
Vagus - anterior and posterior oesophageal plexuses.
157
What is the embryological origin of the azygos vein
The persistent right posterior cardinal vein of the embryo.
158
What is the commencement of the azygos vein
The union of the ascending lumbar vein with the subcostal vein of the right side.
159
Where does it go through the diaphragm
under the right crus.
160
What level does the azygos arch over the right bronchu
T4 vertebra - to enter the SVC
161
What does the azygos vein receive
The lower eight posterior intercostal veins, the superior intercostal vein as it curves and the bronchial veins from the right lung. Some veins from the middle third of the oesophagus and the two hemiazygos veins at the levels of T8 and 9 vertebrae.
162
What are the hemiazygos veins
Two veins that lie longitudinally on the left side of the bodies of the thoracic vertebrae.
163
What do the hemiazygos veins receive
Lower 8 posterior intercostal veins on the left side- inferior vein is the hemiazygos, superior is the accessory hemiazygos.
164
Nerve supply of the parietal pleura
Somatic nerves - intercostals and phrenic nerve
165
Describe the left lung root
Arch of the aorta, then left pulmonary artery, then the left bronchus. All contained in a sleeve of pleura.
166
What is the pulmonary ligament
This is the empty fold of pleura enclosing the root of the lung.
167
Describe the right lung root
Root lies in the curve of the azygos. The bronchus to the upper lobe and the branch of the pulmonary artery to the upper lobe leave the main bronchus outside the lung.
168
What attaches the left pulmonary artery to the aortic arch
Ligamentum arteriosum
169
How many bronchopulmonary segments are there in each lung
10
170
Right lung upper lobe bronchopulmonary segment
Apical, posterior, anterior
171
Left lung upper lobe bronchopulmonary segments
2x apicoposterior, anterior, superior lingular, inferior singular
172
Right lung middle lobe bronchopulmonary segments
Lateral, medial
173
Left lung lower lobe bronchopulmonary segments
Apical, medial, anterior, lateral, posterior
174
Right lung lower lobe bronchopulmonary segments
apical, medial, anterior, lateral, posterior
