Nerves and Plexuses of the Thorax

Question 1

Vagus

Answer 1

CN X

enters superior mediastinum posterior to sternoclavicular joint and brachiocephalic vein

gives rise to recurrent laryngeal nervesm continues to abdomen

distributed into cardiac, esophageal, and pulmonary plexuses

Question 2

Phrenic nerve

Answer 2

anterior rami C3-C5

passes through superior thoracic aperture, runs between mediastinal pleura and pericardium

central portion of the diaphragm

Question 3

Intercostals

Answer 3

anterior rami T1-11

run in intercostal spaces, muscles in and skin over intercostal spaces, lower nerves supply muscles and skin of anterolateral abdominal wall

Question 4

subcostal

Answer 4

anterior ramus T12 nerve

follows inferior border of 12th rib and passes into abdominal wall

abdominal wall and gluteal region

Question 5

Recurrent laryngeal (R)

Answer 5

loops around subclavian artery on the right

Question 6

Recurrent laryngeal (L)

Answer 6

runs around arch of aorta and ascends in tracheo-esophageal groove

intrinsic muscles of larynx

Question 7

cardiac plexus

Answer 7

cervical and cardiac branches of vagus nerve and sympathetic trunk

from arch of aorta and posterior surface of heart, fibers extend along coronary arteries and sinu-atrial nove

impulses pass to sinu-atrial node

Question 8

Pulmonary plexuses

Answer 8

vagus nerve and sympathetic trunk

forms on root of lung, extends along bronchial subdivisions

Question 9

Esophageal plexus

Answer 9

vagus nerve, sympathetic ganglia, greater splanchnic nerve