Flashcards in Thoracic spinal nerves Deck (23)
How many thoracic nerve roots does a normal person have?
24 (12 pairs)
What will each mixed nerve divide into?
a posterior and anterior primary ramus
What does every posterior primary ramus divide into after it projects posteriorward?
medial and lateral branch
Which branch of the posterior primary ramus has motor AND sensory function?
both the medial and lateral branches
What muscles are supplied by the medial branches of the posterior primary rami of the thoracic spinal nerves?
semispinalis (upper 6), longissimus (lower six), and the multifidi (at every level)
What do the medial branches of the posterior primary rami of the thoracic spinal nerves seupply sensory info to?
the skin paraspinally
Which branches of the posterior primary rami increase in size from superior to inferior?
What muscles are supplied by the lateral branches of the posterior primary rami of the thoracic spinal nerves?
longissimus, iliocostalis, and levator costarum
What do the lateral branches of the posterior primary rami of the thoracic spinal nerves supply sensory info to?
skin near the costal angles
T/F: the anterior primary rami of thoracic spinal nerves generally follow the course of the rib below the nerve.
False; generally follow course of rib above the nerve
The anterior primary ramus of T1 will contribute to the brachial plexus and a smaller branch of T1 will form what nerve?
first intercostal nerve
Which anterior primary rami contribute to the intercostobrachial nerve?
T2 and sometimes T1
What nerve is a communcation with the medial cutaneous nerve of the arm?
Each intercostal nerve gives off a lateral cutaneous branch which divides into an anterior branch and a posterior branch. What do these branches supply?
the overlying skin
What do intercostal nerves terminate as and what do these terminal branches supply?
anterior cutaneous branches;
the skin close to midline
What muscles are supplied by the intercostal nerves?
(TIRE SITE) Transverse abdominal, Internal abdominal oblique, Rectus abdominus, External abdominal oblique, Serratus posterior, Internal intercostals, Transverse thoracis, and External intercostals.
What muscles are only supplied by intercostal nerves 7-11?
(TIRE, as in fat belly) Transverse abdominal, Internal abdominal oblique, Rectus abdominus, and External abdominal oblique
T/F: the intercostal nerve also supply blood vessels, bones, joints, and ligaments.
What is the largest of the thoracic nerves?
subcostal nerve (T12)
What plexus does the subcostal nerve contribute to?
How far inferiorly might the skin be supplied by the subcostal nerve?
as far inferior as the superior buttocks
How do thoracic nerves communicate with the sympathetic trunk?
by way of both white and gray rami communicans