Spinal Cord and Back Flashcards
body of vertebrae
weight bearing component
vertebral arch
arches posteriorly to form vertebral foramen which contains spinal cord
pedicle
part of vertebral arch that joins the vertebral body to the transverse process
lamina
paired posterior segments that connect transverse process to spinous process
spinous process
posteriorly projecting tip of the vertebral arch, easily palpated
transverse process
extend laterally from junction of pedicle and lamina
superior and inferior articular processes
form synovial facets that join with vertebrae
Intervertebral foramina
bilateral foramen that between pedicles where spinal nerves go through
how many thoracic vertebrae
12
how many cervical vertebrae
7
how many thoracic vertebrae
5
C7 special factor
C7 has a long, palpable spinous process, and is thus known as the vertebra prominens
atlas
C1, articulates with occipital condyle
axis
dens, C2 “no” head movement
sacrum
5 vertebrae fused into 1
- Promontory – sticks out, where L5 sits
- Articulations with lumbar vertebrae and hip bones – facets of articular process for L5 and auricular surfaces for articulation with ilium
- Sacral canal – continuation of the spinal canal
- Ventral and dorsal sacral foramina (four pairs of each) holes in sacrum for nerves and blood vessels
coccyx
3 to 4 fused vertebrae, “tailbone”
atlanto-occipital joints
synovial joint
flexion and extension of the head. (Nod head “yes”)
atlantoaxial joints
synovial joint
rotation of the head and atlas on the axis (Shake head “no”)
Supraspinous (supraspinal) ligament
connects apices of spinous processes from C7 to sacrum
Ligamentum nuchae (nuchal ligament)
cervical occipital protuberance to C1-C7
interspinous ligaments
connects spinous processes
ligamenta flava
connects paired laminae of adjacent vertebrae
anterior longitudinal ligament
courses longitudinally along anterior surface of the vertebral bodies limiting vertebral extension
posterior longitudinal ligament
courses longitudinally, down posterior surface of bodies
2 portions of inter-vertebral disc
- Anulus fibrosus – tough hyaline cartilaginous rim
- Nucleus pulposus – softer fibrocartilaginous core
normal curvature of vertebral column
- Cervical lordosis – curve anteriorly
- Thoracic kyphosis – curve posteriorly
- Lumbar lordosis – curve anteriorly
- Sacral kyphosis – curve posteriorly
trapezius
most superficial, triangular shape
- Superior – obliquely from occipital bone to scapula, elevates and rotates scapula
- Middle – horizontal, causes scapular retraction
- Inferior parts – superiorly from lower thoracic vertebrae to scapula, scapular depression
- Innervation: accessory nerve
latissimus dorsi
broad flat muscle of lower region of the back
- Action: adduction, medial rotation, and extension of the shoulder joint
- Innervation: thoracodorsal nerve
levator scapulae
deep to the trapezius muscle and superior to the rhomboids
- Action: elevation of the scapula
- Innervation: Dorsal scapular nerve and cervical spinal nerves C3-4
Rhomboid minor
superior to major
- Action: retraction of the scapula
- Innervation: dorsal scapular nerve
Rhomboid major
inferior to minor
- Action: retraction of the scapula
- Innervation: dorsal scapular nerve
what innervates serratus posterior superior and inferior
dorsal rami
erector spinae
innervated by dorsal rami – extend the vertebral column, rotate to ipsilateral side
- Iliocostalis – most lateral
- Longissimus – middle
- Spinalis – most medial, closest to spine
dura mater
most superficial layer of the meninges, forms a sheath around spinal cord
Epidural space
(potential in skull) – between dura mater and vertebral canal
Subdural space
(potential in both skull and spine) – between dura and arachnoid maters
arachnoid mater
intermediate layer, attached to pia by arachnoid trabeculae
subarachnoid space
between the arachnoid and pia mater; contains cerebrospinal fluid (CSF) to suspend the spinal cord, brain and nerve roots
pia mater
deepest layer, inseparable from surface of the spinal cord, contains blood vessels to cord
denticulate ligament
lateral extensions of pia to dura mater for stability, allows “tether”
filum terminale
extension of pia mater beyond spinal cord to attach to coccyx
Cauda equina
spinal cord terminates at L1 in adults, so L2-5 and S1-5 make the cauda equina
Meningitis
inflammation of the meninges, painful because of sensory neuron receptors for pain
enlargements of the spinal cord
Cervical enlargement – result from enlargement of the gray matter that contains the neural machinery necessary to operate the upper limbs C5-T1
Lumbar enlargement – result from enlargement of the gray matter that contains the neural machinery necessary to operate the lower limbs T11-S2
dorsal root
convey sensory afferent information from body tissue to spinal cord
ventral root
convey motor efferent information away from spinal cord to body tissue
conus medullaris
tapered lower end of the spinal cord
gray matter
central, butterfly-shaped mass; the ventral and dorsal parts of the “wings” of the gray matter are called the ventral and dorsal horns, respectively
white matter
periphery mass, contains vertical columns of axons arrange so those that perform similar functions are arranged in tracts
ventral horn in gray matter
contains cell bodies of motor neurons that innervate skeletal muscle
dorsal horn of gray matter
receives sensory impulses entering via dorsal root
vessels that supply spinal cord
anterior spinal artery and two posterior spinal arteries
corresponding veins drain into the internal vertebral venous plexus
