11. Thoracic Neurology Flashcards
what is the thoracic esophagus and where is it located
tube joining laryngopharynx to stomach
T1 & esophageal hiatus or diaphragm (travel thru post mediastinum)
what are the 4 constriction sites of the esophagus & why are they significant
- @ cricopharyngeus M - right below larynx (upper esophageal sphincter)
- @ aortic arch
- @ L. bronchus
- @ esophageal hiatus of diaphragm (lower esophageal sphincter)
-where food can get stuck if not small enough
what are the branches of the vagus N
recurrent laryngeal Ns
cardiac branches
pulmonary branches
esophageal branches
vagal trunks
how do R & L recurrent laryngeal Ns differ
R = off the neck, under subclavian A then back u
L = goes down and loops around aortic arch & ligamentum arteriosum & then back to larynx (prob at arch/ligamentum - hoarse voice)
where do the cardiac branches come off the vagus N
superior & middle @ neck
inferior @ thorax
where do anterior and posterior vagal trunks come from & where to they go
L vagus N –> ant
R vagus N –> post
==> both go to abd via esophageal hiatus
where does the phrenic N travel
what does it do
thru superior thoracic aperature and into space btn the mediastinal parietal pleura & fibrous pericardium
= sensory info from central diaphragm, mediastinal pleura & pericardium
what do the thoracic spinal Ns make
intercostal Ns
(=anterior rami of thoracic spinal Ns)
where do intercostal Ns travel
inf edge of superior rib in intercostal space
& btn internal and inner most intercostal Ms
what do the intercostal Ns innervate
skin
subcutaneous tissue
intercostal Ms
costal/diaphragmatic parietal pleura
which intercostal Ns are atypical & typical
atypical = 1-2 & 7-11
typical = 3-6
what are the branches of the typical intercostal Ns
- rami comunicates
- collateral branches
- lateral cutaneous branches
- anterior cutaneous branches
- muscular branches
what do rami communicates of the intercostal N do
connect intercostal N to ipsi thoracic sym trunk
where are the collateral branches of the intercostal Ns
sup edge of the inf rib in the intercostal space
-innervate intercostal Ms
what do the lateral & anterior cutaneous branches of the intercostal N supply
lateral: skin of thoracic wall
ant: ant skin of thoracic wall
both: T4-6 breast
what Ms are supplied by the muscular branches of the intercostal N
intercostal Ms
subcostal Ms
transverse thoracic Ms
why is the 1st intercostal N different
no cutaneous branches
majority of the superior part blends with the brachial plexus
what is the intercostobrachial N
2nd intercostal N cutaneous branch
-supplies skin & subcutaneous tissue of axilla
why are intercostal Ns 7-11 different
begin as intercostal N and travel anteriorly
but run out of rib to run along –> so become thoracoabdominal Ns
what does thoracolumbar mean
sym ANS (T1-L2)
describe the presynaptic fibers of the sym system
= short
cell bodies in lateral horns of T & upper L
travel in ant root –> ant ramus –> paravertebral ganglia at their own level
what are the options the presynaptic sym fibers can do after reaching the paravertebal ganglion
- synapse at same level –> go to heart/lungs
- ascend/descend –> then synpase
- exit w/o synapsing –> continue as abdominopelvic splanchnic Ns into corresponding prevertebral ganglia in abd
what are cardiopulmonary splanchnic Ns
=post synaptic fibers
cardio part (T1-5/6)
pul part (T1-2)
presyn - synapse in cervical/thoracic sym trunk –> postsyn (these fibers)
what type of fibers are abdominopelvic splanchnic Ns
presynaptic
what is the greater splanchnic N
T5-9/10
send fibers to esophageal plexus & celiac ganglion in abd
-feed into celiac plexus
what is the lesser splanchnic N
T10-11
send fibers to celiac & sup mesenteric ganglion in abd
-feed into sup mesenteric plexus
what is the least splanchnic N
T12
send fibers to aorticorenal ganglion in abd
Sympathetic innervation is sent …
EVERYWHERE
-even smooth Ms, skin, sweat glands, etc
what does craniosacral mean
parasym ANS
describe the parasym presynaptic fibers
long
-nuclei in brainstem & sacral spinal cord
cranial component exit as CNs 3, 7, 9, 10
sacral component exit spinal level as pelvic splanchnic Ns
what 4 ganglion are associated with the parasym ANS
- celiac (CN 3)
- pterygopalatine (CN 7)
- submandibular (CN 7)
- otic (CN 9)
cell bodies of parasym postsyn fibers (close to target organ -short)
where are the cell bodies of the parasym postsyn fibers
in or near traget organ
what makes up the thoracic autonomic plexuses
postsyn fibers of both sym and parasym fibers
what does the pulmonary plexus innervate
lungs, bronchi & pleura
pulmonary plexus sympathetic contribution
pulmonary splanchnic Ns
pulmonary plexus parasym contribution =
pulmonary branches of the vagus N
what does the cardiac plexus innervate
nodal tissue (heart)
superficial - cover ant surface of aorta
deep - ant to bifurcation of trachea, post to aortic arch & sup to bifurcation of pul trunk
cardiac plexus sym contribution
cardiac splanchnic Ns
cardiac plexus parasym contribution =
superior, middle & inferior cardiac branches
of vagus N
what is the purpose of the aortic plexus
conduit of cardiac plexus into intermesenteric plexus
aortic plexus sym contribution =
-what is the fxn
continuous w superficial cardiac plexus
= bronchodilator, vasoconstrictor & visceral sensory
aortic plexus parasym contribution =
what is its fxn
continuous w/ superficial cardiac plexus
=bronchoconstrictor, secretomotor to glands of bronchi/ioles, vasodilator, sensory from brachial mucosa)
esophageal plexus sym contribution
greater splanchnic N & aortic plexus
-inhibt peristalis & esophageal glands
esophageal plexus parasym contribution
esophageal branches of the vagus N
=stimulate peristalsis & esophageal glands
