Spinal Cord/Spinal Nerves Flashcards
vertebrae section/#s
7: Cervical C1-C7
12: Thoracic T1-T12
5: Lumbar L1-L5
common features of all vertebrae
cervical vertebrae
cervical vertebrae - atlas
cervical vertebrae - atlas (medial view)
cervical vertebrae - axis
cervical vertebrae - axis (medial view)
thoracic vertebrae
lumbar vertebrae
intervertebral disk
vertebrae comparison
cervical:
—- transverse foramen (vertebral artery)
thoracic:
—- transverse costal facet (rib articulation)
—- prominent spinous process (muscle attachment)
lumbar:
—- big vertebral body (strength/support)
—- prominent spinous process (muscle attachment)
why do we have process features on the vertebrae?
process: muscle/tendon/ligament attachments
what articulates at the transverse costal facet on thoracic vertebrae?
ribs (costal)
inferior vertebral notch (L2) and superior vertebral notch (L3) creates _____ ?
intervertebral foramen (neural)
less movement in the lumbar region because the superior articular process is bigger or smaller?
bigger
what are the components of the intervertebral disk?
nucleus pulposus
anulus fibrosus
*fibrocartilage
what are the three layers of body wall muscles?
external (superficial)
internal
innermost (deep)
T/F: innermost costal muscles do not wrap all the way around
true
how do abdominal body wall muscles articulate on the anterior (front) side
rectus sheath and the linea alba
abdominal body wall muscle names (4)
transverse abdominis (deep)
internal oblique
external oblique (superficial)
rectus abdominis
spinal nerve distribution
how many nerves innervate the cervical region?
8
C1-C7 nerves exit ABOVE corresponding vertebrae
C8 exits BELOW C7
does T2 spinal nerve exit above or below T2 vertebrae?
BELOW
does C3 spinal nerve exit above or below C3 vertebrae?
ABOVE
conus medullaris location and movement
most distal spinal cord
conus medullaris presents in different locations as we age/grow
lower for newborns (L2)
higher for adults (T12-L1)
conus medullaris
base of spinal cord (last bulk/concentration of spinal cord)
growth of the spinal cord
the spinal cord doesn’t really grow with age but rather slides up through the vertebral foramen
epidural targets the spinal cord at…
below of spinal cord (cauda equina “horse tail”)
around L3/L4
*reduce the risk of piercing the spinal cord
spinal cord cross section components
white matter
lateral horn
posterior horn
central horn
anterior horn
white matter of the spinal cord
fast signal transmission
myelinated
gray matter of the spinal cord
cell bodies and axon terminals located here to synapse
*Communication
neurons that enter spinal cord
afferent
neurons that exit spinal cord
efferent
gray matter components
posterior horn
lateral horn
anterior horn
afferent nuclei
efferent nuclei
posterior horn
sensory
lateral horn
visceromotor
anterior horn
motor
myelination (CNS)
CNS - one oligodendrocyte myelinates one internode on multiple axons
myelination (PNS)
Peripheral Nervous System - one Schwann cell myelinates one internode on a single axon
Myelination electrically insulates ______
Myelination electrically insulates axons, thereby increasing impulse conduction speed
Myelinated neurons have a ___ appearance
white (bc of Schwann cells)
*white matter
White matter
- No synaptic activity present – used for fast transmission of signal
where do we find white matter in spinal cord?
external
where is gray matter located within the spinal cord?
internal surface
*communication - synapse
what occurs in grey matter?
communication
Synapse
why does the thoracic area have less gray matter?
more communication from the rest of the body
NOT SURE CHECK
sensory neuron
cell body is near CNS but not in the spinal cord
motor neuron
cell body innervates in the spinal cord
afferent/sensory neurons enter the spinal cord through the ___
posterior root
afferent/sensory neuron’s cell body is in the
posterior root ganglion
efferent/motor neurons always exit through the ___
ventral/anterior root
afferent neurons ____ the spinal cord
efferent neurons ____ the spinal cord
afferent - enter
efferent - exit
interneuron - synaptic transmission
reside in the spinal cord
NOT myelinated
what spinal neurons are myelinated?
efferent (motor) & afferent (sensory)
*interneuron (synaptic transmission) are NOT myelinated
spinal nerve anatomy
dorsal root (orange) - sensory/afferent
ventral root (red) - motor/efferent
trunk (green) - both eff/aff
dorsal ramus (pink) - back innervation
ventral ramus (blue) - limb/anterior body wall innervation
dorsal ramus
back innervation
contains both efferent and afferent neurons
ventral ramus
anterior body wall and limb innervation
contains both efferent and afferent neurons
2 rami
dorsal ramus
ventral ramus
spinal nerve trunk
very short
contains both efferent and afferent neurons
dorsal root
afferent neurons (sensory)
ventral root
efferent neurons (motor)
you burn your back: nerve trace
dorsal ramus senses pain
trunk
dorsal root
spinal cord
example of the spinal cord and neurons
label:
gray matter (anterior/posterior horn)
white matter
dorsal root
dorsal root ganglion
anterior root
trunk
dorsal ramus
ventral ramus
posterior rootlets
anterior rootlets
pia mater
arachnoid mater
dura mater
epidural space
orient
dorsal (spinous process)
ventral (vertebral body)
dermatome
simple spinal reflex
SAME DAVE
Sensory
Afferent
Motor
Efferent
Dorsal
Afferent
Ventral
Efferent
White vs grey matter
Grey matter processes info (communication)
White matter transmits it to different areas of NS
No question
Cauda equina
Horse tail
Below conus medullaris
Filum terminale
Pia mater that continues interior to the corpus medullaris and cauda equina
How many ribs (section/#)
12 ribs
True ribs: 7
False ribs: 3
Floating ribs: 2
What vertebrae do ribs articulate with?
Thoracic vertebrae
Sternum parts
Manubrium
Sternum angle
Sternum body
Xiphoid process
