Thoracic Neurology Flashcards
(42 cards)
What are the regions of the esophagus?
Cervical part Thoracic part (between T1 and esophageal hiatus of the thoracic diaphragm travels through the posterior mediastinum) Abdominal part
Where can constrictions of the esophagus occur?
At the cricopharyngeus M (clinically referred to as the upper esophageal sphincter)
At the aortic arch
At the left bronchus
At the esophageal hiatus of the thoracic diaphragm (clinically referred to as the LES)
Describe the vagus N
Enters the thorax through superior thoracic aperture
Produces the left recurrent laryngeal N, the pulmonary and inferior cardiac branches on the esophagus
Immediately proximal to entering the abdomen the vagus nerves become an anterior and posterior vagal trunk on the anterior and posterior surface of the esophagus
What are the branches of the vagus N?
Left recurrent laryngeal N, pulmonary branches, inferior cardiac branch, anterior and posterior vagal trunk
Describe the left recurrent laryngeal N
Loops under aortic arch and ligamentum arteriosum to the larynx
Describe the anterior vagal trunk
Derived primarily from the left vagus N
Anterior to the esophagus
Enters the abdomen through the esophageal hiatus
Describe the posterior vagal trunk
Derived primarily from the right vagus N
Posterior to the esophagus
Enters the abdomen through the esophageal hiatus
Describe the phrenic nerve
Anterior rami of C3-5
Travels through the superior thoracic aperture into the space b/w mediastinal parietal pleura and fibrous pericardium
What does the phrenic N innervate?
The thoracic diaphragm
Conveys sensory information from central diaphragmatic and mediastinal pleura and the pericardium
Describe the intercostal N
1-11th pair of anterior rami of thoracic spinal nerves
Travel along the inferior edge of the superior rib in the intercostal space b/w internal and innermost intercostal M
What do the intercostal N innervate?
Skin, subcutaneous tissue, musculature and costal diaphragmatic parietal pleura
What are the typical intercostal Ns?
3rd-6th
Rami communicans, collateral branches, lateral branches, anterior cutaneous and muscular branches
What do the rami communicantes of the typical intercostal Ns connect?
Intercostal N to ipsilateral sympathetic trunk
What is the function of collateral branches of typical intercostal Ns?
Assist in innervating intercostal M
Travels on the superior edge of the rib inferior to the intercostal space
Describe the lateral cutaneous branch of the typical intercostal Ns
Become anterior and posterior branches and supply the skin of the thoracic wall
T4-6 supply the breast
What do the anterior cutaneous branches (of typical intercostal) supply?
Anterior aspect of the thoracic wall
T4-6 supply the breast
What do the muscular branches of the typical intercostal Ns supply?
Intercostal Ms, Subcostal M and transversus thoracis M
Describe the 1st atypical intercostal N
No cutaneous branches and majority superior portion joins the brachial plexus
Describe the 2nd atypical intercostal Ns
Majority travels in the costal groove as a typical intercostal N with a small part joining the brachial plexus
The lateral cutaneous branch supplies the skin and subcutaneous tissue of the axilla and is called the intercostobrachial N
Describe 7th-11th atypical intercostal Ns
Begin as intercostal N but as they travel anteriorly cease to exist between ribs and transition over the abdomen to become thoracoabdominal Ns
Describe the distribution of the PNS
Limited to the head, neck and trunk viscera, never in the body wall or extremities whereas the SNS distributes to all vascular areas of the body
What is glandular secretion stimulated by?
The PNS (except sweat glands)
What can indirectly decrease non-sweat gland glandular secretion through vasoconstriction?
SNS
What stimulates vasoconstriction?
Sympathetics
