Block 2 Thoracic Wall Flashcards
Where does heart reside? and put stethoscope
Mid clavicular line, T4-5th intercostal space. sternal angle
Where does heart reside in patient with cardiomegaly?
below 5th intercostal space, lateral to mid clavicular space
if heart on right what is it called?
dextrocardia
anterior boundaries of thoracic cage?
anterior: sternum, costal cartilages, ribs
posterior boundaries of thoracic cage?
posterior: thoracic vertebrae, ribs
lateral border of thoracic wall?
ribs
the thoracic/chest is described as a space between what
between neck and abdomen
thoracic wall covered outside by ______ and______
skin outside and muscles attaching the shoulder girdle to the trunk
thoracic inlet vs outlet
inlet anatomically, outlet clinically
outlet- vasculature leaves
but same thing
thoracic wall is lined with
parietal pleura
functions of thoracic wall?
- protect internal air- and fluid filled organs
- provide rigid exterior wall to prevent collapse of elastic lungs
- provide attachment and support to upper limbs
- provide auxiliary lung expansion
thoracic inlet boundary?
anterior: upper border of sternum
posterior: 1st thoracic vertebrae
each side: 1st rib and 1st cartilage
sloping downwards and inwards
needle in intercostal space?
NV bundle within costal groove, insert above the costal bone.
if do below, hit intercostal bundle
number of thoracic vertebrae and number of typical thoracic vertebrae number vs atypical
there are total of 12 vertebrae
T2-T9 they are called typical
1, 10, 11, 12 are atypical
typical vertebrae characteristics
body: heart shape and carries 2 demi facet at its side
transverse process: has facet for rib tubercle of same number
spine: long, pointed and directed downward and backward
vertebral foramen: small and circular
sternum parts and levels of the thoracic vertebrae
3 parts
Manubrium: lies opposite T3, T4
Body: lies opposite T5 to T8
Xiphoid: opposite of T9
structures of sternum and their locations
anterior: in front of heart
superior: above heart
posterior: behind heart
true ribs are?
attached to sternum, upper 7 pairs
typical rib
A typical rib is a long twisted flat bone
•Borders:
- Superior
- rounded, smooth
- Inferior
- sharp, thin
- The inferior border overhangs and forms the costal groove, which accommodates the intercostal vessels and nerve.
- The anterior end:
- attaches to the corresponding costal cartilage.
typical rib parts
Parts:•head, neck, tubercle, shaft, and angle.
•The head has two facets for articulation with the numerically corresponding vertebral body and that of the vertebra immediately above.
•The neck is a constricted portion situated between the head and the tubercle.
•The tubercle is a prominence on the outer surface of the rib at the junction of the neck with the shaft- It has a facet for articulation with the transverse process of the numerically corresponding vertebra
•The shaft is thin and flattened and twisted on its long axis.
•Its inferior border has the costal groove.
•The angle is where the shaft of the rib bends sharply forward.
joints of sternum: manubrium and sternum
The manubriosternal joint is a cartilaginous joint between the manubrium and the body of the sternum.
joints of ribs, head, transverse process, costal cartilages
head of rib -> The 1st rib and the three lowest ribs have a single synovial joint with their corresponding vertebral body
Joints of the Tubercles of the Ribs•
The tubercle of a rib articulates by means of a synovial joint with the transverse process of the corresponding vertebra (This joint is absent on the 11th and 12th ribs.)
Joints of the Ribs and Costal Cartilages
•These joints are cartilaginous joints. No movement is possible.
costovertebral joint
Rib has same number as the inferior vertebra and its transverse process
joints of the costal cartilages with the sternum
- The 1st costal cartilages articulate with the manubrium, by cartilaginous joints that permit no movement
- The 2nd to 7th costal cartilages articulate with the lateral border of the sternum by synovial joint
- Additionally, the 6th, 7th, 8th, 9th, and 10th costal cartilages articulate with one another along their borders by small synovial joints.
- The cartilages of the 11th and 12th ribs are embedded in the abdominal musculature.
atypical vertebrae numbers
1, 10, 11, 12
expiration vs inspiration pressures
inspiration pressure of thorax less than atmospheric, breathe in
expiration opposite
clinical communication of thoracic inlet
clinically, the chest cavity communicates with the root of the neck through an opening called the thoracic outlet. •
why is it called an thoracic outlet?
It is called an outlet because important vessels and nerves emerge from the thorax here to enter the neck and upper limbs
boundaries of thoracic inlet
Anatomically:•Called thoracic inlet or the superior thoracic aperture
.•Boundaries:
•Anteriorly: the superior border of the manubrium
- Posteriorly: the first thoracic vertebra (T1)
- Laterally: first pair of ribs & the costal cartilage
•Relations:
•Anterior: Clavicle articulates & manubrium•Superior: The root of the neck
Inferior: superior mediastinum
•Superolateral: The brachial plexus
injry below 5th rib stab what structures affected in possibly which cavity
we reached the abdominal cavity, prob affect something in here now
ie spleen behind 9-11th ribs on left side
liver is behind ribs 9-11 on the right side
structures that pass through thoracic inlet
trachea
•oesophagus
•thoracic duct
-apices of the lungs
- Nerves
- phrenic nerve
- vagus nerve
- recurrent laryngeal nerves
- sympathetic trunks
structures that pass through thoracic inlet nerves
trachea
•oesophagus
•thoracic duct
-apices of the lungs
Nerves
•phrenic nerve
•vagus nerve
•recurrent laryngeal nerves
•sympathetic trunks
vessels that pass through the the thoracic inlet
Arteries
•left and right common carotid arteries
•left subclavian arteries
Veins
•internal jugular veins
•brachiocephalic veins
•subclavian veins
•Lymph nodes and lymphatic vessels
boundaries of thoracic wall
anterior: sternum, costal cartilages, and ribs
posterior: thoracic vertebrae andribs
laterally: ribs
what makes T1 atypical
small body, long horizontal spine, upper complete facet on the body
what makes T11 and T12 atypical
complete facet on the body, inferior articular facet directed laterally, short blunt spine
what makes T2-T9 typical
facets on the body and transverse processes for articulation with ribs, circular or heart shaped body, the spine is long tapering and directing backwards and downwards
what are the atypical ribs?
1st, 2nd, 10th, 11th and 12th
what are the floating ribs and why?
11 and 12, they have no anterior connection with the other ribs or with the sternum
what are the false ribs and why?
ribs pair 8, 9, 10 are false ribs because they don’t articulate directly with sternum, they articulate with anteriorly with the costal cartilages of the ribs above
characteristics of atypical first rib?
shortest, and is C-shaped
anterior end: cup shape
posterior end: head, neck, and tubercle
head: one facet
surfaces: superior and inferior
what muscle attaches to upper and anterior border of first rib?
the scaleneus muscle
what is anterior to the scaleneus muscle and first rib?
the subclavian vein crosses the rib, posterior to the muscle attachment, the subclavian artery and the lower trunk of the brachial plexus cross the rib and lie in contact with the bone
characteristics of the 2nd rib?
the 2nd rib has twice the length of the first rib
head has 2 facets
surfaces of shaft are in between that of the 1st and typical
movements of ribs and costal cartilages
•Movements of the Ribs and Costal Cartilages•The 1st ribs and their costal cartilages are fixed to the manubrium and are immobile. The raising and lowering of the ribs during respiration are accompanied by movements in both the joints of the head and the tubercle, permitting the neck of each rib to rotate around its own axis.
what is the thoracic outlet characterized by?
forms by vertebra T12, rib 12, costal margin, and xiphoid process.
it is bounded inferiorly by the dome of diaphragm.
what can a fracture of lower ribs result in?
diaphragmatic hernia
the lower boundary of diaphragm is problematic because?
Lower boundary arches up so high that a stab wound below rib 5 can pierce the abdominal cavity
how many intercostal spaces are there?
there are 9 anterior and 11 posterior
each intercostal space contains what?
intercostal muscles: (external, internal, and transversus thoracis)
an intercostal nerve
intercostal vessels: intercostal arteries (anterior and posterior)
intercostal veins (anterior and posterior)
order of superficial intercostal muscles? from superficial to deeper
external intercostal muscles, internal intercostal muscles, innermost intercostal muscles
external intercostal muscle origin and insertion
origin: from the lower border of the rib above
insert: into the outer lip of upper border of a rib below the origin
external intercostal muscle action
elevate the ribs during inspiration
external intercostal muscle innervation
intercostal nerves
the external intercostal runs how through the intercostal space? how do fibers run
the fibers are directed from above downwards and forwards toward the belly, they attach more anteriorly than origin
the muscle begins from the posterior end of the intercostal space close to the tubercle of the rib and ends at the costochondral junction where it is replaced by external or anterior intercostal membrane
internal intercostal muscle origin and insertion
origin: floor of costal groove
insertion: inner lip of upper border of rib below
internal intercostal muscle action
depresses the rib downwards during expiration
internal intercostal muscle innervation
intercostal nerves
the internal intercostal runs how through the intercostal space? how do fibers run
the fibers are directed from above, diagonally inferior and posteriorly toward the back. the attach more posteriorly than origin
it begins from the anterior end of the space close to sternum and ends at the angle of the rib where it is replaced by posterior or internal intercostal membrane
what is the internal intercostal membrane traversed by
it is partly traversed by the nerve and vessels which splits each muscle into 2 parts:
Outer: internal intercostal
inner: innermost intercostal
deep muscles of the intercostal space?
innermost intercostals, subcostales, and transversus thoracis
how many anterior intercostal arteries are there?
2 small arteries in each of the 9 spaces
subcostalis muscle where found?
thin band
lower 6 spaces
only in the posterior part of spaces
subcostalis origin and insertion
origin: inner surface and lower border of rib above
insertion: upper border of 2nd and 3rd rib below
the upper 6 anterior intercostal arteries arise from what structure?
the internal mammary artery aka the internal thoracic artery
the lower 3 anterior arteries arise from what structure
the musculophrenic artery
the 1st and 2nd posterior intercostal arteries arise from what
the 1st and 2nd posterior intercostal artery arise from the the superior intercostal artery of the costocervical trunk from the 2nd part of the subclavian artery
the lower 9 posterior intercostal arteries and subcostal arteries arise from what?
the descending thoracic aorta
in each space the posterior intercostal artery and its collateral branch ________ with the 2 ________ intercostal arteries
anastomose with the 2 anterior intercostal arteries
how many anterior intercostal veins are there?
2 in each of the 9 spaces, so a total of 36 (18 each side)
the 1st, 2nd, and 3rd anterior intercostal veins drain into what
join the internal mammary vein aka the internal thoracic vein
the 4th, 5th, and 6th anterior intercostal veins join?
the venae commitantes of internal mammary artery
the 7th, 8th, and 9th anterior intercostal veins join?
the venae commitantes of the musculophrenic artery
the internal mammary vein drains into what
the innominate (brachiocephalic vein)
how many posterior intercostal veins are there?
there are one each of the 11 spaces, so 22 total (11 on each side)
the 1st right posterior intercostal vein drains into?
right innominate vein
the right 2nd, 3rd, and sometimes the 4th posterior intercostal vein drains into what?
they unite to form right superior intercostal vein which drain into the azygos vein
the right sided 5th-11th and subcostal veins drain into ?
azygos vein
the left 1st posterior intercostal vein drains into
left innominate vein
the left 2nd, 3rd, and sometimes 4th posterior intercostal veins join to form what?
the left superior intercostal vein which drains into the left innominate vein
the left 5th, 6th, 7th, and 8th posterior intercostal veins form?
the superior hemiazygos vein which join to the azygos vein
the left 9th, 10th, and 11th posterior intercostal veins and subcostal veins form ?
they form the inferior hemiazygos vein which drains into the azygos vein
the intercostal nerves are formed by the ______ of spinal thoracic nerves from T_ to T_
anterior/ventral primary rami of spinal thoracic nerves from T1-T11
the typical intercostal nerves are T_ to T_
T3-T6 are typical
T12 spinal nerve is also called what
subcostal nerve
the atypical intercostal nerves are
T1, T2, T7-T12
order of NV bundle in costal groove
VAN
Vein is superior
Artery
Nerve most inferior
course of typical intercostal nerves T_ to T_? which eventually forms the what nerve?
from T3-T6 the intercostal nerves are ventral rami of spinal thoracic nerves that leave the intervertebral foramen to reach the intercostal space. They run between pleura and posterior intercostal membrane. The nerve(s) pierces the internal intercostal muscle splitting it into the internal intercostal (proper) and the innermost intercostal. Runs between internal intercostal muscle and pleura. Pierces internal intercostal muscle, anterior intercostal intercostal membrane, pectoralis major and deep fascia to become anterior cutaneous nerve.
intercostal nerve branches
- white and grey communicans with sympathetic ganglion
- collateral branch to intercostals
- lateral cutaneous branch to skin
- anterior cutaneous
- muscular branches
- pleural sensory branches
- peritoneal branches
- articular branches
1st intercostal nerve
joined to the brachial plexus, by a branch that is equivalent to the lateral cutaneous branch
the 2nd intercostal nerve
joined the medial cutaneous nerve of the arm, by a branch called the intercostobrachial nerve (corresponds to lateral cutaneous branch)
in angina pectoris and myocardial infarcation pain, pain referred to _____ of arm by what nerve?
medial side of the arm by the 2nd intercostal nerve ie the medial cutaneous nerve of the arm
the upper 6 intercostal nerves supply _____ , _____, and _____ in each space
supply skin, parietal pleura, and intercostal muscles in each space
tube thoracostomy procedure
- skin incision at anterior axillary line
- incise skin over one below space to be pierced
- scalpel and eventually tube must pass through skin, fascia, intercostal muscles (EIM, IIM, innermost IM) , and parietal pleura
- incise through intercostal space to upper border of rib to avoid injuring the intercostal vessels and nerve
- advance tube posteriorly and superiorly in the pleural space to avoid puncturing lungs or other structures in cavity
radicular artery
comes from posterior intercostal artery run along the posterior and anterior roots of the spinal nerves and supply them with blood. a clot in radicular artery causes infarction to spinal cord
the internal thoracic artery or internal mammary artery supplies what
supplies the anterior wall of the body from clavicle to the umbilicus
the internal thoracic artery is a branch of what?
it is a branch of the first part of the subclavian artery in the neck
the internal thoracic artery descends vertically on _____ behind ______ just ______ to the sternum. The internal thoracic artery ends in the ______ intercostal space by dividing into the ________ and ______ arteries
descends vertically on the pleura behind the costal cartilages just a fingerbreadth length lateral to the sternum. The internal thoracic artery ends in the 6th intercostal space by dividing into the superior epigastric artery and musculophrenic artery
the internal thoracic artery branches to form the _____ for the upper _____ intercostal spaces
2 anterior intercostal arteries for the upper 6 intercostal spaces
the internal thoracic artery branches into _____ arteries which accompany the terminal branches of the corresponding ______ nerves
perforating arteries which accompany the corresponding intercostal nerves
the internal thoracic branches to form the __________ artery, which accompanies the phrenic nerve and supplies the ______
pericardiaphrenic artery, accompanies the phrenic nerve and supplies the pericardium
the internal thoracic artery has ____ major branches? which are ?
- Anterior intercostal arteries in the 6 upper intercostal spaces
- perforating arteries
- percardiaphrenic artery
- mediastinal arteries
- superior epigastric artery
- musculophrenic artery
the internal thoracic artery branches to this artery that supplies contents of the anterior mediastinum (eg thymus)
mediastinal arteries
the internal thoracic artery branches to the _______ which enters the rectus sheath of the anterior abdominal wall and supplies _______ as far as the _______
superior epigastric artery, supplies the rectus muscle as far as the umbilicus
the internal thoracic artery branches to the _______ which runs around the costal margin of the diaphragm and supplies _______
musculophrenic artery supplies the lower intercostal spaces (lower 3 anterior ICAs) and the diaphragm
the internal thoracic vein accompanies ________ and drains into the _______ on each side
the internal thoracic vein accompanies the internal thoracic artery and drains into the brachiocephalic vein on each side
the superior intercostal aka the supreme intercostal artery derives from _____ which is a branch from the ____ part of the _____ artery. the SIA forms what intercostal arteries and supplies what
superior intercostal artery derives from the costocervical trunk which is a branch of the 2nd part of the subclavian artery. the superior intercostal artery forms the posterior 1st and 2nd intercostal arteries and supplies the first and 2nd intercostal spaces
the azygos vein connects the ___ with the _____
connects IVC with SVC
the azygos vein begins in abdomen from back of the _____ at the level of _____
back of the IVC at level of L2
the azygos vein enters the thorax through the ______ of the diaphragm on the _____ side of the aorta and the _____
the azygos vein enters thorax through aortic opening of the diaphragm on the right side of the of the thoracic duct and the aorta
in the ______ mediastinum, the azygos vein passes behind ______ of and root of _____ lung
in the posterior mediastinum, the AV passes behind the right border of the esophagus and root of right lung
in the _____ mediastinum at level of T_, the azygos vein crosses above the root of _____
superior mediastinum at level of T4, the azygos vein crosses above the root of the right lung
the azygos vein enters the ____ of the SVC
enters middle back of the SVC
in the azygos vein, blood flows ____ to the ____ vena cava, entering the SVC on the _____ side. This allows an alternate route back to the ____ when the _____ or ___ is blocked
blood flows superiorly to superior vena cava, entering the SVC on the posterior side. this allows an alternate route back to the heart when the IVC or SVC is blocked.
the thoracoepigastric vein provides what
an alternate circulation route when there is liver disease
superficial lymphatic drainage, the _____ drain 75% of the lymph from breast and the ____ nodes drain rest
axillary nodes most, parasternal drain rest
what structure is closely associated with the axillary nodes? what does this mean clinically
the long thoracic nerve is in close association. Removal surgical of axillary nodes can accidentally hit LTN, causing winging of scapular
the diaphragm is a _____ and tendinous ______ that separates the ____ cavity above from the ____ cavity below
it is a thin muscular and tendinous septum that separates thoracic/chest cavity above from abdominal cavity below
what pierces the diaphragm?
structures that pass between chest and abdomen
diaphragm shape
it is dome shaped (left and right dome)
the right dome of the diaphragm reaches what structure
upper border of the 5th rib
the left dome of the diaphragm reaches what structure
reaches lower border of 5th rib
the diaphragm consists of 2 parts which are
- peripheral muscular part (arises from the margins of the thoracic opening)
- centrally placed tendon
the diaphragm origin is divided into 3 parts which are?
- a sternal part (from the posterior surface of the xiphoid process)
- a costal part (from the deep surfaces of the lower six ribs and their costal cartilages)
- a vertebral part (raising by vertical columns or crura and from the arcuate ligament)
the right crus originates from
the bodies of the upper 3 lumbar vertebrae (L1, L2, L3) and their IVDs
the left crus originates from
the bodies of the upper 2 lumbar vertebrae (L1 and L2) and their IVDs
lateral to the crura the diaphragm arises from the ______ and ______ ligament
medial and lateral arcuate ligament
the medial arcuate ligament extends from _____ to the tip of ________ of ______
the medial arcuate ligament extends from the side of the body of the L2 vertebrae to the tip of the transverse process of the 1st lumbar vertebrae
the lateral arcuate ligament extends from _____ to the lower border of _________
from the tip of the transverse process of the first lumbar vertebra to the lower border of the 12th rib
the medial borders of the two crura are connected by a ______ which crosses over the the anterior surface of the _____
connected by median arcuate ligament which crosses over the anterior surface of the aorta
the medial arcuate ligaments is the thickened _______ covering the anterior surface of the _______
the thickened upper margin of the fascia covering the psoas major muscle
the lateral arcuate ligaments is the thickened _______ covering the anterior surface of the _______
the thickened upper margin of the fascia covering the quadratus lumborum muscle
the median arcuate ligament connects the ____ borders of the 2 _____. This ligament crosses over the anterior surface of the _____ at level of T_
the median arcuate ligament connects the medial borders of the 2 crura. it crosses over the anterior surface of the aorta at level of T12
the diaphragm inserts into ____ this lies at which point
a central tendon which is shaped like3 leaves, a trifle. The central tendon lies at the xiphsternal junction
the nerve supply to diaphragm
motor: the roots of C3, C4, C5 form the left and right phrenic nerves. 3, 4, 5- keep the diaphragm alive!
sensory: the parietal pleura and peritoneum covering the central surfaces of the diaphragm are from the phrenic nerve
the periphery of the diaphragm is from the lower six intercostal nerves
diaphragmatic openings: the caval opening, where located when houses?
the caval opening is at the level of T8, it allows passing of the IVC and right phrenic nerve
diaphragmatic openings: the esophageal opening, where located when houses?
opening at T10
allows passage of: esophagus, vagus nerve, esophageal branches of the left gastric vessels and lymph vessels
diaphragmatic openings: the aortic opening, where located when houses?
level of T12,
transmits:
aorta,
thoracic duct,
azygos vein
diaphragmatic openings: other than the major openings, the diaphragm allows what to pierce?
- splanchnic nerves
- superior epigastric vessels
- left phrenic nerve
diaphragm action/function
pulls down its central tendon and increases the vertical diameter of the thorax
the diaphragm is a muscle of inspiration, abdominal straining, weight lifting, and thoracoabdominal pump
inspiration: decrease pressure in lungs, air rushes in as atmospheric pressure is higher
abdominal straining: micturition (urination), defecation (pooping), parturition( giving birth)
weight lifting (can strengthen)
thoracoabdominal pump: caval lymphatic force increases by increasing intra-abdominal pressure
clinical significances of diaphragm
hiccup- involuntary spasmodic contraction of the diaphragm
paralysis of the diaphragm- lost of control of one or both sides of the diaphragm, shortness of breath
penetrating injury to diaphragm- any penetrating wound below level of nipples should be suspected of causing damage to the diaphragm
diaphragmatic hernia- may occur in middle age person due to weak musculature, abdominal organs can creep in thoracic cavity
