The vertebral column Flashcards
how many vertebrae in vertebral column
33
how many vertebrae in each region
cervical 7 thoracic 12 lumbar 5 sacral 5 coccygeal 4
characteristics of cervical vertebrae
have transverse foramen for the vertebral artery
motion occurs between how many vertebrae and which
24 vertebrae
7 cervical
12 thoracic
5 lumbar
sacrum is
fused
coccyx
tailbone is fused
primary curvatures of the spine
thoracic and sacral
what is a primary curvature
curvatures that developed during the fetal period
what is a secondary curvature
develop post-natal in the opposite direction as the vertebral column
how does the cervical curve arise
when infants begin to hold their head up
how does the lumbar curve arise?
when infant starts to stand/walk/pull self up
kyphosis
hunchback
accentuated of thoracic spine
age related osteoporosis
kyphosis
lordosis
accentuated lumbar curvature often due to weight gain (ex pregnancy)
sway back or hollow back
lordosis
scoliosis
abnormal lateral curvature and rotation of vertebral column
can result from limb length inequalities and or malformation of the vertebrae
3 general features of a vertebrae
vertebral body
vertebral (neural) arch (pedicles and lamina)
processes for muscular attachment (7)
vertebral processes for muscular attachment
spinous process 1
transverse process 2
articular processes (superior and inferior) 4
articular processes
form the facet joints
synovial joints between the superior and inferior articular processes of adjacent vertebrae
facet joints
individual facets
small range of motion
collective facets
larger degree of motion
intervertebral discs
cartilaginous joints designed for weight bearing and strength
provide a strong stable attachment between adjacent vertebrae
intervertebral disc has 2 parts
annulus fibrosus
nucleus pulposus
annulus fibrosus
composed of concentric layers of fibrocartilage that adheres to the vertebral bodies
nucleus pulposus
a gelatinous central mass (high water content) that acts like a miniature shock absorber
intervertebral foramina
allow passage and protection for the spinal nerve as it exits the vertebral process
articular process facets of cervical
oriented at 45 degrees off the transverse plane
thoracic vertebrae facets
- have costal facets that articulate with the ribs
- articular processes are oriented in the frontal plane (dorsal and ventral)
lumbar facets
articular processes are oriented in sagittal plane (right and left)
what determines the motion of the vertebral column?
the shape and orientation of the facet joints
where does the majority of motion occur along the vertebral column?
cervical and lumbar regions
what areas are prone to significant stress concentration?
cervicothoracic junction and thoracolumbar junction
the ___________ spine is at greatest risk of injury purely from a mechanical standpoint
cervical
followed by lumbar
first cervical vertebrae
atlas
a ring shaped bone which consists of two lateral bony masses connected by an anterior and posterior arch
atlas
anterior arch has a facet for the ______
dens of C2
2nd cervical vertebra
axis
distinguishing feature of C2
dens = toothlike process that projects superiorly from the body
craniovertebral joints
- Atlanto-occipital
- Atlanto-axial
yes movements
primarily flexion and extension in the sagittal plane
Jefferson fracture
fracture of atlas (C1)
-burst fracture of C1 (compression of cervical region)
synovial joint between the superior articular facets of the atlas and the occipital condyles at the base of the skull
atlanto occipital joint
Atlanto-axial joints
one median atlantoaxial joint between the dens of C2 and the anterior arch of C1
two lateral antlantoaxial synovial joints between opposing articular facets
“no” movements
movement of Atlanto-axial joint in the transverse plane
hangman fracture
fracture of axis (c2)
may involve the dens which if displaced can injure the spinal cord
functions of the vertebral column
- supports the head and trunk
- transfers weight the body to the lower limbs
- provides postural support
- encloses and protects the spinal cord and nerves
the spinal cord has ___ pairs of spinal nerves
31
some branches of spinal nerves come together and form _____ that innervate structures in the limbs
plexuses
ventral root
contains axons of somatic motor (efferent) nerves that convey impulses away from the spinal cord
dorsal root
contains axons of somatic sensory (afferent) nerves that convey impulses toward the spinal cord
both roots unite to form a ______ which conveys both ___ and _____ axons
spinal nerve
sensory and motor
spinal nerves divide into ____ branches or ____ which also convey both sensory and motor axons
two
rami
convey nerve axons to and from the deep muscles of the back and the overlying skin of the back
dorsal ramus
conveys nerve axon to and from the body wall and/or upper and lower limbs
ventral ramus
ligaments of the vertebral column
- anterior longitudinal ligament
- posterior longitudinal ligament
- supraspinous ligament
- interspinous ligament
- ligamentum flava
unites anterior surfaces of the bodies of the vertebrae and prevents hyperextension
anterior longitudinal ligament
unites the posterior surface of the bodies of the vertebrae located inside the vertebral canal
posterior longitudinal ligament
supraspinous ligament
connects the spinous processes from the sacrum to c7
ligamentum nuchae
brand strong ligament of the neck that provides attachment for cervical muscles
interspinous ligament
in-between each adjacent spinous process
ligamentum flavum
a yellow ligament with elastic fibers that join adjacent lamina or vertebrae - help prevent hyper flexion of the vertebral column
things that can impinge upon the exiting spinal nerve
arthritis or disc degeneration
ligament affected in whiplash
anterior longitudinal ligament
