Exam 2: Spinal Cord & Spinal Nerves

Question 1

Posterior median sulcus

Answer 1

Posterior groove that divided the spinal cord into a left & right side

Question 2

Anterior median fissure

Answer 2

Deeper grove on anterior side that divides the spinal cord into a L&R side

Question 3

Cervical enlargement

Answer 3

Nerves of shoulders & upper limbs

Question 4

Lumbar enlargement

Answer 4

Nerves of pelvis & lower limbs

Question 5

Conus medullaris

Answer 5

Thin, conical spinal cord below lumbar enlargement

Question 6

Cause equina

Answer 6

“Horse tail”

Nerve roots extending below conus medullaris

Question 7

Film terminale

Answer 7

Thin thread of fibrous tissue at end of conus medullaris

Attaches to coccygeal ligament

Question 8

Ventral root

Answer 8

Branch of spinal nerves that contain axons of motor neurons

Question 9

Dorsal root

Answer 9

Branch of spinal nerves that contains axons of sensory neurons

Question 10

Dorsal root ganglion

Answer 10

Contains cell bodies of sensory neurons

Question 11

Spinal nerve

Answer 11

Dorsal & ventral roots join to form spinal nerve

Pass at the intervertebral foramen btwn 2 vertebrae

Question 12

Mixed nerves

Answer 12

Spinal nerves are mixed nerves

Carry both afferent (sensory) & efferent (motor) fibers

Question 13

Meninges

Answer 13

Specialized membranes isolate spinal cord from surroundings

Spinal meninges:
Protect spinal cord
Carry blood supply
continuous with cranial meninges

Question 14

Meningitis

Answer 14

Inflammation of meninges; viral or bacterial infection

Stiff neck
Confusion
Severe headache
Sensitivity to bright light
Fever
Sleepiness
Nausea
Vomiting

Question 15

Spinal dura mater

Answer 15

Tough & fibrous

Cranially: end oatmeal layer fused w/ periosteum

Caudally: tapers to a dense cord, joins film terminale in coccygeal ligament

Question 16

Epidural space

Answer 16

Btwn walls of vertebral canal & dura mater

Contains loose connective & adipose tissue

Question 17

Spinal anesthesia “epidural block”

Answer 17

Injection of a mixture of local anesthetic & anti inflammatory to control inflammation & pain

Question 18

Arachnoid mater

Answer 18

Covered by simple squamous epithelia

Question 19

Subdural space

Answer 19

Btwn dura & arachnoid mater

Used for spinal anesthesia

Question 20

Subarachnoid space

Answer 20

Btwn arachnoid & pia mater

Contains collagen/ elastin fiber network arachnoid trabeculae

Filled with CSF

Question 21

CSF

Answer 21

Found in subarachnoid space

Spinal tap: withdraw CSF

Question 22

Pia mater

Answer 22

Innermost meningeal layer

Mesh of collagen & elastic fibers

Bound to underlying neural tissue

Question 23

White matter

Answer 23

Superficial

Contains myelinated & unmyelinated axons

3 columns:
Posterior white column
Lateral white column
Anterior white column

Question 24

Gray matter

Answer 24

Surrounds central canal

Contains neuron cell bodies & neuroglia

Has projections: gray horns

Question 25

Posterior gray horn

Answer 25

Contain somatic and visceral sensory nuclei

Question 26

Lateral gray horns

Answer 26

In thoracic and lumbar segments

Contain visceral motor nuclei

Question 27

Anterior gray horns

Answer 27

Contain somatic motor nuclei

Question 28

4 major nerve plexuses

Answer 28

Complex, interwoven networks of nerve fibers

Control skeletal muscles

Question 29

Cervical plexus

Answer 29

Included ventral rami of spinal nerves C1-C5

Inner area neck, thoracic cavity & diaphragmatic muscles

Major nerve: phrenic nerve (controls diaphragm)

Question 30

Brachial plexus

Answer 30

Includes spinal nerves C5-T1

Inner area pectoral girdle & upper limbs

Question 31

Lumbar & sacral plexuses

Answer 31

Innervate pelvis girdle & lower limbs

Question 32

Herniated disc

Answer 32

Discs consist of 2 layers:
Outer, fibrous ring, annulus fibrosus
Inner, soft portion, nucleus pulposus, which can bulge out causing inflammation & nerve root compression

Question 33

Spinal cord

Answer 33

~ 18 in. long & 1/2 in. wide

ENDS BTWN L1 & L2