Exam 3 Study Guide- Dr. Butt

Question 1

What forms the spinal nerve?

Answer 1

it is the structure present at the junction at the dorsal root

Question 2

How long is the spinal nerve?

Answer 2

It’s typically a very short structure

Question 3

What happens to the spinal nerve once it exits the IVF?

Answer 3

once the spinal nerve exits the IVF, it begins to branch

Question 4

What is a spinal segment?

Answer 4

The spinal cord is located in the vertebral foramen and is made up of 31 segments: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral and 1 coccygeal

Question 5

What is the function of the sympathetic nervous system?

Answer 5

-“Fight-or-flight response” -“Total body Response”

Question 6

What is the function of the parasympathetic nervous system?

Answer 6

SLUDD: Salivation, Lacrimation, Urination, Digestion, and Defecation. Also includes sexual arousal, peristalsis, GIT secretions, mitosis, and Bronchoconstriction

Question 7

Why does the sympathetic nervous system have a much more diffuse whole body

Answer 7

axons of preganglionic sympathetic neurons will synapse with many postganglionic neurons which then terminate in widely separated organs Innervation of adrenal medulla by preganglionic sympathetic neurons results in release of epinephrine and norepinephrine into the blood stream

Question 8

What are some effects you would expect to see in a person under sympathetic stimulation?

Answer 8

-Mydriasis -Increase rate and force of contraction of heart -Dilation of coronary blood vessels -Elevation of blood glucose -Bronchodilation -Increase blood flow to skeletal muscle – dilate blood vessels -Cutaneous vasoconstriction -Constriction of blood vessels in digestive organs -Increased breakdown of stored fats -Piloerection -Diaphoresis – sweating - cholinergic -Ejaculation -Immune effects

Question 9

Where do you find cerebral spinal fluid?

Answer 9

choroid plexus - found in wall of ventricles -Produce CSF

Question 10

Where does the spinal cord begin? End?

Answer 10

Arises from brainstem at the foramen magnum and pairs down to just below L1 in adult. Spinal cord ends at conus medullaris

Question 11

What is found in the grey and white matter of the brain and spinal cord?

Answer 11

Spinal Cord: Gray mater: nerve cell bodies - multipolar, central canal White mater: nerve cells - bundle of myelinated sensory and motor neurons Brain: Gray: cell bodies

Question 12

Spinal Meninges: Dura Mater- External Layer

Answer 12

-Spinal dura continuous with cranial dura - in cranial cavity: one layer of dura IS fused to skull -In veterbral column: dura is NOT fused to bone - extradural space -Dural sac ends at S2-3 vertebral level -Dura portion of film terminals - attaches to coccyx

Question 13

What is found in the grey and white matter of the brain and spinal cord?

Answer 13

Spinal Cord: Gray mater: nerve cell bodies - multipolar, central canal White mater: nerve cells - bundle of myelinated sensory and motor neurons Brain: Gray: cell bodies of axons White: myelinated axons

Question 14

Ascending tracts carry___? Descending tracts carry____? (type of fiber) (afferent vs efferent)

Answer 14

Ascending tracts: carry Sensory information (afferent) Descending tracts: carry motor info. (efferent)

Question 15

What are denticulate ligaments? Where can they be found?

Answer 15

ligaments only in spine attaching Pia mater to the dura mater - 20-22 sawtooth attachments of the Pia to the dura -serve to suspend the spinal cord within the dural sac -extend from the foramen magnum to T12-L1

Question 16

Where does the meninges end?

Answer 16

dural sac (spine) ends at S2-3 vertebral level

Question 17

What fibers are found at the spinoreticular tract? Gracile fasiculus? Cuneate fasciculus? Anterior corticospinal? Vestibulospinal?

Answer 17

Spinoreticular tract- Sensory Gracile fasiculus- Sensory Cuneate fasciculus- Sensory Anterior corticospinal- Motor Vestibulospinal- Motor

Question 18

Know the difference between visceral motor, somatic motor, visceral afferent, somatic afferent

Answer 18

visceral motor- autonomic motor fibers to smooth muscle, cardiac, and glands somatic motor: Contraction of skeletal muscle visceral afferent- receptors in walls of blood vessels (smooth m), body organs, heart, glands, also in tongue, and nasal epithelium somatic afferent- receptors in skin, joints, skeletal muscle, also eye and ear

Question 19

Spinal Meninges: Pia Mater- Deep Layer

Answer 19

-Thin delicate membrane -Denticulate ligaments

Question 20

What fibers are found at the spinoreticular tract? Gracile fasiculus? Cuneate fasciculus? Anterior corticospinal? Vestibulospinal?

Answer 20

Spinoreticular tract- Sensory Gracile fasiculus- Sensory Cuneate fasciculus- Sensory Anterior corticospinal- Motor Vestibulospinal- Motor

Question 21

Where does recurrent meningeal nerve come from? What structures does it innervate?

Answer 21

is a branch or rami of spinal nerve and typically more than one branch Innervates: -posterior aspect of IVD -posterior longitudinal ligament -anterior epidural veins -anterior aspect of the dura

Question 22

What structure does the posterior rami innervate?

Answer 22

skin and intrinsic (epaxial) muscles of the back out to the level of the lateral column of the erector spinae group - carries sympathetic fibers to structures of the back - zygapophyseal joints

Question 23

What structures does the anterior rami innervate?

Answer 23

the continuum of the spinal nerve once all branches have come off of it -It is the “Root” of the spinal nerve- called spinal nerve root, called ventral rami, anterior rams, or just nerve root -tissues innervated- supply motor, sensory, and sympathetic fibers to the anterior and lateral (hypaxial) muscles and skin of the neck and trunk and all the muscles and skin of LIMBS, including superficial back muscles - Form plexuses -T1-T12 ventral rami form the intercostal nerves

Question 24

Where will you find the cervical plexus? Which nerves carry sensory and which carry motor fibers?

Answer 24

C1-C4(5) (mainly ventral rami of C2, 3 and 4) Sensory branches: carry afferent (GSA, GVA) info Transverse Cervical Nerve - C2, 3 - skin of anterior neck Supraclavicular Nerves - C3, 4 - 3 Lesser Occipital Nerve - C2 (C3) - Greater Auricular Nerve - C2, 3 - 2 branches anterior branch - skin over parotid salivary gland posterior branch - skin over the mastoid process and ear lobe Motor branches: carry efferent info Ansa cervicalis - C1, 2, 3 - motor to omohyoid, sternohyoid, sternothyroid Phrenic Nerve - C3, 4, 5 - motor to the diaphragm –“keeps the diaphragm alive”

Question 25

What muscles are innervated by Obturator? What are the roots of this nerve? What are the actions of these muscle? Any afferents, where?

Answer 25

L2,3,4 motor - adductor longus m., adductor brevis m., gracilis m., obturator externus m., adductor magnus m. sensory - skin of the medial thigh

Question 26

What is the cutaneous distribution of lateral cutaneous femoral and what are the nerve roots?

Answer 26

L2,3 sensory - skin over the lateral and anterior thigh

Question 27

What muscles are innervated by Superior gluteal nerve? What are the roots of this nerve? What are the actions of these muscle? Any afferents, where?

Answer 27

L4,5,S1 motor gluteus minimus and medius mm. and tensor fasciae latae m. no cutaneous sensory branch

Question 28

What muscles are innervated by inferior gluteal nerve? What are the roots of this nerve? What are the actions of these muscle? Any afferents, where?

Answer 28

L5,S1,2 motor - gluteus maximus m. no cutaneous sensory branch

Question 29

Which nerves make up the sciatic nerve? What are their roots? What is the sensory and motor component of each nerve. ( common fibular will split, so include it’s distribution as well.)

Answer 29

L4,5,S1,2,3 actually 2 nerves in one neural sheath. It splits into its two respective divisions just proximal to the knee. As the sciatic nerve, it descends through the posterior thigh sending branches to the hamstrings and adductor magnus m.

Question 30

What muscles are innervated by Ilioinguinal? What are the roots of this nerve? What are the actions of these muscle? Any afferents, where?

Answer 30

L1 motor - part of the internal and external abdominal obliques mm.and transverse abdominis m. sensory - skin of upper medial aspect of the thigh, root of the penis and scrotum, labia majora and mons pubis Damage to nerve: Seen in some surgical procedures to repair inguinal hernias Patients complain of a loss of feelings to an area called the “hands in pockets” area.

Question 31

What muscles are innervated by Iliohypogastric? What are the roots of this nerve? What are the actions of these muscle? Any afferents, where?

Answer 31

L1 motor - muscles of the anterolateral abdominal wall sensory - skin of the lower abdomen and buttock

Question 32

What muscles are innervated by Genitofemoral? What are the roots of this nerve? What are the actions of these muscle? Any afferents, where?

Answer 32

L1,2 2 branches motor - genital branch - cremaster m. sensory - femoral branch - skin of middle anterior surface of thigh, scrotum - in male and labia majora in female

Question 33

What muscles are innervated by Femoral? What are the roots of this nerve? What are the actions of these muscle? Any afferents, where?

Answer 33

L2,3,4 motor to iliacus m. pectineus m., sartorius m., quadriceps sensory - skin of anterior and medial thigh Saphenous n. - off of femoral n. - skin of medial aspect of thigh and leg and foot