Spinal Cord Flashcards Preview

Anatomy! Written 1 > Spinal Cord > Flashcards

Flashcards in Spinal Cord Deck (36):
1

Spinal Cord lives in the...

Vertebral Canal

2

Spinal Cord is a continuation of the...

medulla oblongata

3

Spinal cord begins and ends...

Begine at the foramen magnum and ends at the L2 vertebral body
Occupies 2/3s of the vertebral column
It tapers and terminates at L2
Vertebral levels and spinal level do NOT line up

4

Conus Medullaris

Terminal portion of the spinal cord

5

Neuron

Cell body and dendrites
1 nerve = thousands of neurons

6

Spinal Cord... Matter

Gray Matter = neurons, colelction of cell bodies without myelination, centrally located in the spinal cord
White Matter = Myelinated axons and dendrites, don't have the cell bodies, located outside the gray matter in spinal cord

7

Enlargements of the Spinal Cord

Cervical = upper limb innervation
Lumbosacral = lower limb innervation

8

Cauda Equina

Tail horse
All the nerve rootsgoing to go find their foramen to get out of the canal
Location = lumbar Cistern (subarachnoid space)
Dorsal and ventral rootlets are located in the subarachnoid space and are directed towards the intervertebral foramen to exit the vertebral column
Includes conus medullaris and the filum terminale

9

Filum Terminale

Anchors the cord
No nerve process! It is a membrane

10

Vasculature of the Spinal Cord

Anterior Spinal Artery = Anterior midline of the spinal cord
Posterior Spinal Artery = splits and stays apart

11

Spinal Meninges

Dura Mater = thick membrane/sac
Arachnoid Mater = filmy/glassy layer inside dura mater
Pia Mater = most intimate layer, anchor, runs the grooves of the cord

12

Dura Mater

Contains the epidural space
- Outside the dura mater (epidural anesthesia)

13

Arachnoid Mater

Contains the subarachnoid space - fluid under the layer
CNS floats in this space
Lumbar Cistern = collects the cerebrospinal fluid

14

Pia Mater

Contains the denticulate ligaments (saw tooth arrangements) and the filum termnale (comes off the conus medullaris) is an anchor

15

Typical Spinal Nerves come off the...
How many pairs of spinal nerves?

Spinal Cord
Cranial nerves = off of the brain
31 pairs of spinal nerves
8C, 12T, 5L, 5S, 1C - Pair - Right and Left

16

Definition of a nerve

Collection of neuronal cell processes, dendrites (sensory) and axons (motor) surrounded by conenctive tissue coverings

17

Dermatomes and Myotomes

Dermatomes = sensory nerve distribution (C3 and 4 = shoulder, T4 = nipple)
Myotomes = motor nerve distribution

18

Neuron

Basic functional unit of the nervous system (dendrite = re --> cell body --> axon --> dendrite

19

Synapse

Functional communication between a series of neurons

20

Afferent

Neuron that send impulses towards the CNS
Sensory

21

Efferent

Neuron that sends impulses away from the CNS
Motor

22

Somatic

Pertaining to the body; typically the body wall

23

Visceral

Splanchnic
Pertaining to the gut, viscera

24

Ganglion

Collection of cell bodies outside of the CNS

25

Rootlets

Within subarachnoid space
Directed toward intervertebral foramina
Immediately come off of the spinal cord
Dorsal - sensory
Ventral - motor

26

Roots

Cabeled up rootlets
Dorsal - Afferent
Ventral - Efferent

27

Dorsal Roots

Dorsal Root Ganglion - collection of cell bodies outside of the CNS, Swelling, Located within the intervertebral foramen of the vertebral column
Sensory neuronal processes contained in a conenctive tissue sheath

28

Ventral Roots

Motor neuronal processes contained in a connective tissue sheath

29

When do they become mixed?

When they pass the rootlets and the roots... at the spinal nerve

30

Mixed Spinal Nerve

31 pairs
Both motor and sensory neuronal processes combined in a conenctive tissue sheath
Named and numbered corresponding to location and relationship to the vertebrae
C1 comes out above atlas though so C8 comes out below C7 (after that it lines up again)

31

Rami

Dorsal Primary Ramus - Synovial joints of the vertebral column, Deep muscles of the back (motor), and Overlying skin of the back (sensory)
Ventral Primary Ramus - Remaining areas of the trunk, upper limbs, lower limbs, all of the nerve plexuses
Cervical (C1-5), Brachial (C5-T2), Intercostal (T1-T11), Lumbar (T12 - L4), Sacral (L4 - S5), Coccygeal (C0)

32

Components of a typical spinal nerve

General Sensory (General Somatic Afferent)
Somatic Motor (General Somatic Efferent)
Visceral Sensory (General Visceral Afferent)
Visceral Motor (General Visceral Efferent)
Connective Tissue Coverings (Endoneurium, peri, epi)
Vasa Nevorum (blood vessels)

33

General Sensory (General Somatic Afferent)

Transmits pain, temp, touch, pressure, and proprioception to the spinal cord
you can feel it consciously

34

Somatic Motor (General Somatic Efferent)

Transmits impulses from the spinal cord to skeletal muscles
Conscious muscle movement

35

Visceral Sensory (General Visceral Afferent)

Transmits reflex pain from viscera, glands, mucous membranes and blood vessels to spinal cord (stretch and chemistry)

36

Visceral Motor (General Visceral Efferent)

Transmits impulses from CNS to smooth muscle and glandular tissue (ANS)