Nerve Plexi

Question 0

What are the characteristics of Intercostal Nerves

Answer 0

Come from anterior Rami
Between the ribs
Have lateral and anterior branches
*Intercostobrachial (T2) has a lateral branch that runs from torso to armpit
*Subcostal Nerves=T12 nerves b/c they are under the floating ribs (not b/w ribs)

Question 1

What are the 3 ways in which spinal nerves are distributed in the body

Answer 1

1) Intercostal Nerves
2) Dorsal Rami
3) Spinal Nerve Plexuses

Question 2

Dorsal Rami are also known as…

Answer 2

Posterior Rami

Question 3

Ventral rami are also known as…

Answer 3

Anterior rami

Question 4

Nerve Plexuses

Answer 4

Interweaving anterior rami of spinal nerves
They split into various “named” nerves that innervate various body structures
Main Plexuses=Cervical, Brachial, Lumbar, & Sacral

Question 5

Cervical Plexus

Answer 5

C1-5, Consists of nerve branches
Hypoglossal, Accessory, Lesser Occipital, Great Auricular, Transverse Cervical, Ansa Cervicalis, Supraclavicular, Phrenic, & Branch to Brachial Plexus

Question 6

What nerve extension of the cervical plexus controls motor muscles of the front of the neck?

Answer 6

Ansa Cervicalis (C2/C3)

Question 7

C1 of the cervical plexus has which nerve(s)?

Answer 7

Hypoglossal & Accessory Nerves

Question 8

C2 of the cervical plexus has which nerve(s)?

Answer 8

Lesser Occipital & the Superior and Inferior roots of the Ansa Cervicalis

Question 9

C3 of the cervical plexus has which nerve(s)?

Answer 9

Greater auricular, Transverse cervical, & Phrenic nerve

Question 10

C4 of the cervical plexus has which nerve(s)?

Answer 10

Supraclavicular Nerves & Branch to Brachial Plexus

Question 11

C5 of the cervical plexus has which nerve(s)?

Answer 11

Mainly brachial plexus

Question 12

What do cervical nerves 3-5 control?

Answer 12

Diaphgram

Question 13

Brachial Plexus

Answer 13

Consists of C5-T1 and 5 main nerves

Musculotaneous nerve, Axillary nerve, Radial nerve, Median nerve, & Ulnar nerve

Question 14

What are the 5 components of the nerves in the brachial plexus?

Answer 14

Real Texans Drink Cold Beer
Roots
Trunks
Divisions
Cords
Branches

Question 15

C5 of the brachial plexus has which nerve(s)?

Answer 15

Musculotaneous nerve, Median nerve, & Long thoracic nerve

Question 16

C6 of the brachial plexus has which nerve(s)?

Answer 16

Musculotaneous nerve, Median nerve, & Long thoracic nerve

Question 17

C7 of the brachial plexus has which nerve(s)?

Answer 17

Musculotaneous nerve, Median nerve, Axillary and Radial nerves, and Long thoracic nerve
*Axillary and Radial nerves are dorsal nerves

Question 18

C8 of the brachial plexus has which nerve(s)?

Answer 18

Contributions to Axillary, Radial, & Median nerve…Contains Ulnar nerve

Question 19

T1 of the brachial plexus has which nerve(s)?

Answer 19

Contributions to Ulnar nerve and Long thoracic nerve

Question 20

In the brachial plexus, which nerves (of 5 main) go Lateral, Medial, & Posterior?

Answer 20

Lateral- Musculotaneous & Median
Medial- Ulnar & Median
*Lateral and Medial nerves are also anterior nerves
Posterior- Radial & Axillary

Question 21

Lumbar Plexus

Answer 21

L1-L4 & contains 6 major nerves

*L5 unites lumbar plexus and sacral plexus (Lumbrosacral Trunk)

Question 22

L1 of the Lumbar plexus has which nerve(s)?

Answer 22

Iliohypogastric & Ilioinguinal nerves & contributions to Genitofemoral nerve

Question 23

L2 of the lumbar plexus has which nerve(s)?

Answer 23

Contributions to Genitofemoral, Lateral femoral cutaneous, & Femoral nerves

Question 24

L3 of the lumbar plexus has which nerve(s)?

Answer 24

Contributions to the Lateral Femoral Cutaneous, Femoral, & Obturator nerves

Question 25

L4 of the lumbar plexus has which nerves?

Answer 25

Lumbosacral nerve (connects lumbar and sacral plexuses)

Question 26

L5 of the lumbar plexus has which nerves?

Answer 26

Lumbosacral trunk & component of sciatic nerve

Question 27

Sacral Plexus

Answer 27

L5-S4, contains 6 main nerves

Question 28

L5 of sacral plexus contains which nerves?

Answer 28

Lumbosacral trunk & component of the sciatic nerve

Question 29

S1 of the sacral plexus contains which nerves?

Answer 29

Contributions to the Superior gluteal, Inferior gluteal, Posterior femoral cutaneous, & both the Common fibular division & the Tibial division of the sciatic nerve

Question 30

S2 of the sacral plexus contains which nerves?

Answer 30

Contributions to the Inferior gluteal, Piriformis, Posterior femoral cutaneous, Pudendal, & both the Common fibular and Tibial divisions of the sciatic nerve

Question 31

S3 of the sacral plexus contains which nerves?

Answer 31

Contributions to the Posterior femoral cutaneous, Pudendal, & Tibial division of sciatic nerve

Question 32

S4 of the sacral plexus contains which nerves?

Answer 32

Pudendal nerve

Question 33

What are the characteristics of Reflexes?

Answer 33

Rapid, automatic, involuntary reactions of muscles or glands to a stimulus Awareness of stimulus occurs after reflex action has completed Have 3 main properties

Question 34

What are the 3 main properties of Reflexes?

Answer 34

Stimulus: A stimulus is required to initiate a response Rapid Response: Few neurons are involved and synaptic delay is minimal Automatic Response: Occurs the same way every time

Question 35

Ipsilateral Arc

Answer 35

When both receptor and effector organs of the reflex are on the same side of the spinal cord EX: Left arm muscles contract to move left hand off something hot

Question 36

Contralateral Arc

Answer 36

Sensory impulses from receptor organ cross over the spinal cord to activate the effector organ on the opposite side EX: Step on sharp object with right foot and muscles in left leg contract to help you balance as you raise your right foot

Question 37

Monosynaptic Reflexes

Answer 37

Interneurons are not involved | EX: Patellar knee jerk...muscle spindles in the quadriceps are stretched upon tapping with reflex hammer

Question 38

Polysynaptic Reflex

Answer 38

Complicated neural pathways that exhibit a number of synapses involving interneurons with the reflex arc EX: Pulling hand away from hot stove

Question 39

Stretch Reflexes

Answer 39

Monosynaptic reflexes where if a stimulus results in stretching of a muscle, that muscle reflexively contracts EX: Patellar knee reflex

Question 40

Golgi Tendon Reflex

Answer 40

Prevent skeletal muscles from tensing excessively Nerve endings near muscle-tendon junctions When activated, signal is sent to CNS that inhibits the action of the motor neurons and causes the muscle to relax