Vertebral Column Flashcards
Function of vertebral column
support weight, protect spinal cord, serve as axis and pivot, aid posture/movement
Number of cervical vertebrae
7
Number of thoracic vertebrae
12
Number of lumbar vertebrae
5
Number of sacral vertebrae
5
vertebral arch
made of paired laminae and pedicles
pedicles
join vertebral arch and body
laminae
flat plates contacting pedicles
vertebral foramen
forms vertebral canal; spinal cord runs through
superior and inferior vertebral notches
form IV (interbertebral foramina); spinal nerves and arteries exit through
spinous process
1 per vertebra; posterior
transverse process
2 per vertebra
articular process/zygapophysis
4 per vertebra, 2 superior and 2 inferior
cervical transverse foramina
convey vertebral arteries
cervical anterior and posterior tubercles
on transverse processes
carotid tubercle
anterior tubercle of C6
uncinate process
raised margins of superior border of vertebral body
C3-C7 vertebral foramina
larger due to cervical enlargement of spinal cord
C1 characteristics
articulates with occipital condyles, lacks vertebral body, groove for vertebral artery on superior surface
C2 characteristics
dens/odontoid process - former body of C1, pivot for skull
C7/ vertebra prominens
long spinous process
Thoracic vertebrae characteristics
costal facet for rib head and tubercle; spinous process - long and slender
Lumbar accessory process
posteriorly on each transverse process
attachment for intertransverse lumborum muscles
Lumbar mamillary process
attachments for multifidus and median intertransverse muscles
L5
largest vertebra in column;
huge contributor to lumbosacral angle
lumbosacral angle
angle between lumbar and sacral vertebrae
Sacrum functions to
transfer body weight to pelvis and contribute to strength and stability
sacral canal
sacral continuation of vertebral canal
sacral foramina
between vertebrae; exit for sacral spinal nerves
sacral promontory
anterosuperior projecting edge of S1
median crest
fused spinous processes
medial crest
fused articular processes
lateral crest
fused transverse processes
sacral hiatus
gap in laminae; inferior end
sacral cornua (horns)
former inferior articular processes of S5
aricular surface
part of sacroiliac joint; connects pelvis to sacrum
Coccygeal
rudimentary tailbone
coccygeal cornua (horns)
part of Co1, articulate with sacral horns
Cervical curvature
anteriorly convex, secondary
Thoracic curvature
anteriorly concave, primary
Lumbar curvature
anteriorly convex, secondary
Sacral curvature
anteriorly concave, primary
Primary curvatures
present at birth, due to differences in A & P portions of vertebrae
Secondary curvatures
primarily develop after birth, due to differences in A & P portions of IV discs
Movements of vertebral column
flexion/extension, lateral bending, & rotation
Movement restricted by
IV discs, orientation of zygapophysial joints, articular capsules, muscles, & ligaments
Vertebral body joints
articulate via interposed IV discs; secondary cartilaginous joints
anulus fibrosus
outer portion of concentric fibrocartilaginous circles
nucleus pulposus
slightly posteriorly positioned gelatinous, elastic, avascular core
Unconvertebral joints
joints between uncinate processes of C3-C6 and superjacent body
Vertebral arch joints (zygapophyses)
synovial joints between superior and inferior articular processes; allow gliding between vertebrae; variable orientation limits movements
anterior longitudinal ligament
strong band extending across anterolateral vertebral bodies and IV discs
prevent hyperextension of vertebral column, stabilizes vertebral body joints
extends from sacrum to occiput & C1’s anterior tubercle
posterior longitudinal ligament
weaker band extending along anterior aspect of vertebral canal
Prevents hyperflexion of vertebral column
Prevents herniation/protrusion of discs
ligamenta flava
broad, yellow fibrous tissue extending along posterior wall
connect adjacent laminae
prevents abrupt flexion of vertebral column, preventing injury to IV discs
interspinous ligaments
connect spinous processes
supraspinous ligaments
connect tips of spinous processes, extends from C7 - sacrum
merges with ligamentum nuchae
nuchal ligament/ ligamentum nuchae
extends from external occipital protuberance/ posterior foramen magnum to spinous processes of cervical vertebrae
inter-transverse ligaments
connects adjacent transverse processes
atlanto-occipital joint
between atlas & head
allows nodding of head (flexion/extension); lateral bending and rotation
atlanto-occipital membranes
extend from atlas to margins of foramen magnum
prevents excessive movement
Cruciate ligament
includes transverse ligament, longitudinal bands, & alar ligaments
transverse ligament of atlas
holds dens of C2 with arch of C1
posterior wall of dens socket
longitudinal bands
extend from transverse ligament to occiput and C2 body
alar ligaments
extend from sides of dens to C1 & foramen magnum
limits head rotation
tectorial membrane
extends from C2 and through foramen magnum
superior continuation of posterior longitudinal ligament
atlanto-axial joint
between atlas and axis
movement is primarily rotation
C1 and skull rotate on C2, limited by alar ligaments
C1/C2 zygapophysial joints
gliding joints
dens and C1 articulation
pivot joint
Spinal arteries in neck
vertebral and ascending cervical artery
Spinal arteries in thorax
posterior intercostal arteries
Spinal arteries in abdomen
subcostal & lumbar arteries
Spinal arteries in pelvis
iliolumbar & lateral and medial sacral arteries
terminal radicular arteries
supply ventral and dorsal roots
medullary segmental arteries
anastomose with spinal cord’s arteries
