Exam 3: Thoracic Spinal Nerves Flashcards Preview

GM PNS > Exam 3: Thoracic Spinal Nerves > Flashcards

Flashcards in Exam 3: Thoracic Spinal Nerves Deck (20)
Loading flashcards...

How many nerve pairs are in the thoracic spinal nerves

12 pairs of thoracic nerve roots


Which division (ant or post primary ramus) divides into a medial and lateral branch

Posterior primary ramus


What muscles are supplies by the medial branches of the posterior primary ramus

Semispinalis (upper 6), longissimus (lower 6), multifidi


What sensory supply is from the medial branch of the posterior primary ramus

Sensory supplies skin paraspinally


What branches increase in size from superior to inferior

Lateral branches of posterior primary ramus


What muscles are supplied by lateral branches of the posterior primary ramus

Longissimus, iliocostalis, levator costarum


Where do the lateral branches of the posterior primary rami provide sensory info to

Sensory supply to skin near costal angles


What course do the anterior primary rami follow

Course of the rib above the nerve


The anterior primary ramus of T 1 contributes to what

The brachial plexus, small branch forms the first intercostal nerve


What nerve is contributed to from the anterior primary rami of T2 and T1 sometimes

Intercosotobrachial nerve


Each intercostal nerve gives off what that divides into anterior and posterior branches and what does it supply

Lateral cutaneous branch supplies the overlying skin (back to costal angle)


Where do intercostal nerves terminate and what do they supply

They terminate as anterior cutaneous branches that supply skin close to the midline


Intercostal nerves course along their adjacent ribs giving off muscular branches to supply what?

Internal, external, innermost intercostals/ serratus post/ transversus thoracis and others 7-11


Intercostal nerves 7-11 course along adjacent ribs to supply what specifically along with the other muscles of intercostal nerves

Transverse abdominal, internal abdominal oblique, external abdominal oblique, rectus abdominus (TIRE)


Besides musculature what else do intercostal nerves supply

Adjacent blood vessels, bones, joints, and ligaments


What nerve is the largest of the thoracic nerves and where is it from?

Subcostal nerve from T12


What else does the subcostal nerve contribute to besides normal intercostal nerve innervations

Contributes to lumbar plexus and can supply skin as far inferior as the superior buttocks


What is another name for the subcostal nerve supplying skin to superior buttocks

Cluneal nerves


Each thoracic nerve communicates with _____ by way of both _____ and ____ communicans

Sympathetic trunk/white/gray


What is the difference in location between gray and white communicans

Gray ramus is medial and at all 12 levels (postgang symp nonmyelinated), white ramus is more lateral and only located at T1-L2 (pregang symp. Myelinated fibers)