lecture 6: thoracic wall Flashcards
what is the thoracic cage
osteocartilagenous structure that encloses the thorax and thoracic viscera
give some examples of thoracic viscrea
heart, lungs, esophagus etc
what is tthe rib cage bounded by
by the thoracic vertebrae, ribs and sternum
what is the rib cage walled off by
muscles and conneective tissue with a few key passageways
how many ribs are thre
12
what are the 2 openings of the rib cage
=superior thoracic aperature (thoracic inlet)
=inferior thoracic aperature (thoracic outlet)
which is larger the superior or inferior tthoracic aperature
the inferior
what are the true ribs
1-7
why are ribs 1-7 considered true ribs
direct insertion to the stternum via the costal cartilage
what are the false ribs
8-10
why are ribs 8-10 considered false ribs
they have an indirect insertion on sternum via costal margin (with the rib above them)
what are the floating ribs
11-12
why are ribs 11-12 called floating ribs
no insertion on the sternum att al l
what is it the costal margin
The costal margin is the medial margin formed by the cartilages of the seventh to tenth ribs
-anterior side of tthe thoracic outlet
what are the importtant features of a typical rib
head, tubercle, neck, costal angle, costal groove, body of the ribs, costal carttlage
do the tubercle and costal groove lie inferior or superior
inferior
where is the neck of the rib loacted
betweemn the head and the tubrecle
what are the 3 articulations of the rib
1) hed of the rib (posterior, veertt)
2) tubercle of the rub (posterior, vert)
3) costal cartilage (anterior, sternum)
is the articulation of the head of the rib located posterior or anterior
posterior
is the articulation of the tuebrcle of the rib located posterior or anterior
posterior
is the articulation of the costal cartilage of the rib located posterior or anterior
anterior
where dos the head of the rib articulate
with the body of the vert (on the demi facets)
where dos the ttubercle of the rib articulate
on the veertebra (specifcally on the costal facet on thte transverse process)
whatt are the facets on the vertebral body of the thoracic vert called
demi facets
whatt are the facets on the transverse process of the thoracic vert called
costal facet
how many joint facets are unique to the thoracic vert
3 joint facets
true or false: the ribs associate with the vert of the same nmber
ttrue
where is the costotransverse joint located
betwen the rib and the transverse process
explaiin the articulation of the costotransverse joint
rib at TP
=tubercle of the rib articulates with the costal facet on the TP of the same numbered vertebra
truue or false: tubercle of the rib articulates with the costal facet on the TP of the vertebra above
false, of the same numbereed vertebra
explain thee articulation at the costovertbereal joint
rib at VB
= head of the tubercle articulatese with 2 demi facets:
1) the VB of the same numbered vert and 2) the inferior demi facet of the VB above
what are the posterior joints of the thoracic cage
costotranverse jointt
costcovertebral joint
true or false: rib 7 only acticulates with T7 (
false, also the inferior demi facet of t6
which rib is condered short flat and horizontally oriented
rib 1
what is special about the grooves on rib 1
anterior and psoterior grooves for subclavian vein and artery
what is the articulation of the costovertberal joint of rib 1
articulates with VB of its own level only.
what is the articulation of the costovertberal joint of ribs 10,11,12
the costovert joint articulatest with VB of own level only (no inferior facetts on t10,t11,t12)
true or false: ribs 1,10,11,12 only articulate with VB of own level only
yes
what is the missing physical feature of ribs 11,12
no tubercles or neck
which ribs are shorter than normal
floating (11,12)
whatt are tthe physical features of the sternum
jugular notch
manubirum
sternal angle/manubriosternal jointt
body of the sternum
xiphisternal joint
xiphoid process
what level is the sternal angle/manubriosternal jt
at tthe level of t4-t5
what level is the xiphisetrnal jt
level of T9
what are the anterior joints of the rib cage
1) costochondral
2) sternocostal
3) interchondral
what typee of joint is the costochondral joint
solid, synchondrosis
what typee of joint is the sternocostal joint
synovial, plane/gliding
(exception: 1st rib-synchondrosis)
what is the only rib that has an exception in terms of the sternocostal jt
1st rib is syncondhrosis
where is the interchodnral joints loxated
between costal cartilageese of false ribs (8-10)
what ttype of joints are interchondral
uniquely synovial
what are the 2 movements of the thoracic cage for respiration
pump handle movement
bucket handle movement
explain the pump handle movement
volume of the thoracic cavity changes in an anteerior to posterior axis
in the pump handle movement, where are there smaller movements and why
three are smallre movements superiorly (because of solid synchondrosis joints) and larger movement inferiorly
where does the movement of tthe pump handle movement come from
costotransverse/vertebral of ribs 1-6
explain the bucket handle movementt
laeteral (side to side) changes in thoracic cavity voke
what joints are responsible for the bucket handle movement
costotransverse, costcovert and sterno costal joints for rib 6-12
what muscle is responsible for forcee inspiration
extternal inteercostal muscles
be able to know thee diffeerence in muscle oritenttaiton between exetrnal and internal interncsotals
l
what is the fiber oritentation of the external intercostals
from orgin to isnertion (anterior and inferior)
what is the function of external intercostal muscles
elevates ribs.
forceful inspiration
what muscles are responsible for forces expiration
internal intercosttal
innermost intercostals
transversus thorasis
what is thee fiber orientation for intternal intercostals
from oirgin to insertion, posterior to infeerio
what is the function of the internal intercosatl muscles
depresses ribs
forceful expiration
what is the fiber direction for innermost intercostal muscles
psoterior, inferior (like internal intercostals)
what is the functino of the innermost intercostaks
depresses ribs
forceful expiration
where is tthe transversus thoracis located
sternum body and xiphoid process to ribs 2-6
what is the function of transversus throracic
depresses ribs, froceful expiration
how many intercondral joints are there
betwteen 3 and 4
does the neurovasculature for thee thoracic wall come from anterior or postterior rami
anterior
what are the main nerves that innervate the tnoracic wall
Intercostal n (t1-t11) and subcostal n (t12)
=anterior rami of thoracic spinal n
what is the function of intercostal and subcostal nerves
motor/sensory
what are some of the nerves tah branch off the intercostals
lateral cutaneous neve and anterior cutaneous
what is lateral and anterior cutaneuous nerve responsible for
somattic sensory
wwhat is a dermatone
area/region of the skin innerevated by a single spinal nerve
what is the dermatome area for t4
nipple
what is the dermatome area for t6
skin over xiphoid process
what is the dermatome area for t10
umbilicus
what is the nerve responsible for nipple dermatome
t4
what is the nerve responsible for skin over xiphoid dermatome
t6
what is the nerve responsible for umbilicus dermatome
t10
what si the clinical signigicance of thoracic dermatomes
youu can have pathology associated to 1 nerve root
ex: shnigles
explain shingles
lies dorman in spinal nerve
=affected is spinal cord level tt5 since its right below the nipple which is t4
what is the blood supply for the thoracic wakk
thoracic aorta
posttrior intercostals
anterior intersoclsa
internal thoracic
what two veins form an anastomosis in the thoracic wall
the posterior and anterior intercostatls
where do the posterior intercostatls branch off
thoracic aorta
wheree do the anterior intervostals branch off from
the internal thoracic (which is off the subclavian)
true or false: the anterior and psoterior drainage of the thoracic wall is the same
false, the anterior side is paired with the blood but the posterior side is diff
what is an anastomosis
joining of arterial supply in opp. direction
what is the neurovascular bundle under the costal groove
intercosttal nerve, artery and vein
what is the order of the vessels under the costal grove (sup to inferior)
intercostal vein, arterey nerve
VAN
between what muscles is the intercostal nerve
betweeen innermost and intercostals
what is the clinical significanc eof the neurovasculature bundle
where to insert a chest tube
why is the left domee of the diaphram lower
because of the heart
what is the diapgram involved in
normal resting breathing
what level is the diaphragm located during resp
att rib 5
true or false: thoracic cavity volume chanes in an inferior to superior axis
no , opposite
what is the innervation of the diaphragm
phrenic nerve (anterior rami of spinal nerves c3-c5
truee or false: the sphenic splits to leeft and right
true