Anatomy - Thorax Flashcards
For the thoracic wall
Openings: Skeleton parts: Joints: Intercostal spaces: Muscles:
Openings: superior and inferior thoracic apertures
Skeleton: sternum, twelve pairs of ribs, twelve thoracic vertebrae
Joints: intervertebral discs, costovertebral, sternocostal, sternoclavicular, costochondral, interchondral joints
Intercostal spaces: intercostal vein, artery, nerve
Muscles: intercostal muscles, (external, internal, innermost), transversus thoracis, subcostals, levatores costarum, serratus posterior superior, serratus posterior inferior muscles
The attachments of diaphragm can be divided into?
The attachments of diaphragm can be divided into peripheral and central attachments.
It has three peripheral attachments:
Lumbar vertebrae and arcuate ligaments.
Costal cartilages of ribs 7-10 (attach directly to ribs 11-12).
Xiphoid process of the sternum.
The parts of the diaphragm that arise from the vertebrae are ? in structure, and are called?
The parts of the diaphragm that arise from the vertebrae are tendinous in structure, and are called the right and left crura.
Right crus – Arises from? Some fibres from the right crus surround what opening
Left crus – Arises from?
Right crus – Arises from L1-L3 and their intervertebral discs. Some fibres from the right crus surround the oesophageal opening, acting as a physiological sphincter to prevent reflux of gastric contents into the oesophagus.
Left crus – Arises from L1-L2 and their intervertebral discs.
The pathways through the diaphragm and their vertebral levels:
What are the contents?
3 Hiatuses:
1) Cava hiatus (T8): Vena Cava, terminal branches right phrenic nerve
2) Oesophageal Hiatus (T10): R+L Vagus nerve, Oesophageal branches of Left gastric artery and vein
3) Aortic hiatus: Thoracic duct, azygous vein, Aorta.
Trick for remember ing the level of diaphragm hiatuses?
A tip for remembering the vertebral levels: vena cava has eight letters (T8), oesophagus has ten letters (T10) and aortic hiatus has twelve letters (T12).
Functions of the trachea and bronchi
Large airway conduits for gas exchange.
Pathway of expectoration
The trachea begins
At the inferior edge of the hypopharynx, which is the inferior edge of the cricoid cartilage. At the level of C6.
The trachea ends at:
In the thorax at the level of the sternal angle (T4) at the carina which is the bifurcation of the trachea.
How much does the carina move with deep inspiration?
Movers from T4 to T6
How big is the carina?
12cm long, 2.5cm wide
Describe the trachea
Large airway conduits for gas exchange.
Pathway for expectoration
12cm long, 2.5cm wide fibrocartilagenous tube, whose structure is maintained by “u shape” bars of hyaline cartilage.
begins at the inferior edge of the hypopharynx, which is the inferior edge of the cricoid cartilage. At the level of C6. In the thorax at the level of the sternal angle (T4) at the carina which is the bifurcation of the trachea.
Carina moves between T4 and 6 on deep inspiration.
Relations of the cervical trachea
Superior: Hypopharynx, inf edge cricoid, isthmus of thyroid (anterior superior)
Anterior: sternothyroid and sternohyoid
muscles, anterior jugular veins and JUGULAR VENOUS ARCH
Posterior: oesophagus, recurrent laryngeal nerve, Cervical vertebrae.
Lateral: Carotid sheath, lobes of thyroid
Relations thoracic vertebrae:
Anterior: sternum, origins of right brachiocephalic and left common carotid arteries, left brachiocephalic veins
Posterior: oesophagus left recurrent laryngeal nerve
Left: aortic arch, left common carotid, left subclavian artery, left vagus, left phrenic and recurrent laryngeal n, pleura
Right: azygos vein, right vagus and pleura
The lining of the trachea:
Respiratory epithelium:
Ciliated PSEUDOstratified columnar epithelia, w/mucous glands (goblet cells)
Mnemonic for segments of the lung. State which bits are basal and which lingular.
ALSO applies to?
Right Lung:
A PALM Seed Makes Another Little Palm
- Capitals are upper and middle: APA = upper Apex, post, ant. LM = middle, lat and med
- lower case is lower lobe: everything but superior has basal in thename - i.e Lateral basal segment
Left Lung:
ASIA ALPS
ASIA = UL + Lingular (Sup and Inf LINGULAR segments)
ALPS = LL = Superior segment, then all the rest have BASAL in their name, i.e Lateral basal Segment
The above also applies to bronchi
Relations of the right and left main pulmonary veins (also their tibutaries are?)
The right main pulmonary veins: passes the right atrium and superior vena cava inferiorly; the left in front of the descending thoracic aorta.
What does the aortic arch loop over?
1) Left main bronchus or bifurcation
2) Bronchial arteries (which emerg from the anterior surface of the aorta just before the arch)
3) bifurcation of pulmonary trunk
Main branches of aortic arch
Right: branchiocephalic trunk (i.e needs to be simple because Right and left brachiocephalic kinda in the way)
Left (proximal to distal): Left common carotid, left subclavian artery
what nerve closely associates with the aortic arch?
The left vagus.
On the right the vagus travels over the subclavian proximal to the bifurcation, giving of a branch of the recurrent laryngeal which loops under and goes back up
1st branch of left brachiocephalic vein?
right thyroid vein (this can come off the bifurcation though)
The highest lymph nodes of the thorax are stations?
Where are they?
The next
The next
The next
The trachial nodes are Left Right, except 3 which are Ant Post. Highest - upper - retro - lower.
1 R and 1L “Highest mediastinal nodes”
Superior trachea, just superior to origin of right subclavian
2R and 2L Left upper paratracheal - above arch
3A and 3P are anterior and posterior trachial (3A is prevascular behind bifurcation of SVC.
4R and 4L are lower paraterachial
The next groups of thorax nodes after the trachea (but not the bronchi)
Rule: All nodes not paired (i.e. no r/L, A/P) number from 1-8 going down trachea, 8 paraeosphageal. 5 = subaortic 6 = Paraaortic 7 = Subcarinal 8 = paraeosphageal
After the paraeosphageal nodes, what comes next?
All are paired R+L 9 = pulmonary lig nodes R+L then 10 is hilar nodes at the main bronchus (this are adjacent to 7 = subcarinal) 11 Bifurcation = interlobular nodes 12 = lobular 13 = segmental 14 = subsegmental nodes
Branches of the left main bronchus
Left main becomes Left superior lobular and left inferior lobular - The ASIA ALPS
Right main: the superior, middle and inferior lobular branches, then A PALM Seed Makes Another Little Palm
Sensory innervation of the trachea:
Recurrent laryngeal nerve
Describe the right main bronchi:
4cm long
wider and more vertical than left bronchi
Extends from carina to hilum of lung
Gives of superior lobular branch before entering the lung, where divides into middle and inferior.
Relations:
- Superio-inferior to right pulmonary artery
- Azygous crosses over it
Describe the LEFT main bronchi:
6cm long, thinner than left and runs more horizontally
Extends from carina to hilum where it dives into inferior and superior lobular branches.
Relations:
Passes under the arch of the aorta, anterior to the descending part. Anterior to eosophagus
Innervation of the bronchi?
Left and right vagus
Venous supply to bronchi:
Right: Bronchial veins to azygous
Left drain to accessory hemi-azygous
How do the right and left main bronchus differ in terms of branching?
The main bronchus is short, quickly giving off a a superior lobular branch after which it becomes the intermediate segment. The left main bronchus is relatively longer, and does not have and intermediate branch.
Describe the heart:
Pyramidal shaped hollow muscular fist size organ with apex directed anteriolaterally to the left. Apex, base and three surfaces: Sternocostal Diaphragmatic Pulmonary Positioned in middle mediastinum Covered in fiberous pericardial sac Function is as a pump to return deoxygenated blood from the venous system and recirculate oxygenated blood returning from the pulmonary veins
Surfaces of the heart
Apex, base
Diaphragmatic surface
Sternocostal
Pulmonary
The base of the heart is mainly formed by?
Why
Mainly formed by left atrium
This surface dominated by the pulmonary veins
