Vertebrae Flashcards
Pars intercularis
Oblique area between superior and inferior articular processes.
Different from lamina as lamina between spinal process and transverse
Spondylolysis
Fracture at vertebral arch
Excessive hyperextension in athletes may cause
Unilateral or bilateral
Hairline fracture or complete separation
Spondylolythesis
Complete fracture with forward slippage
Typically occurs at L5/S1 90% of the time
Movements and their respective planes?
Saggital: Flex and extend
Coronal: Lateral flex
Transverse: Rotation
What is joint coupling?
Lateral flexion and rotation linked together, cannot occur without the other
Body shape of vertebrae
Cervical: Oval
Thoracic: Heart shaped
Lumbar: Kidney bean
Foramen of canal of vertebrae
Smaller as you go down except plexus areas
Transverse process?
only cervical unique: transverse foramen (for vertebral artery, vein, and sympathetic nerves)
Spinous processes of vertebrae?
Cervical: Bifid except C7 (looks like thoracic)
Thoracic: Long, slender, downwards (limits extension, protects spinal cord)
Lumbar:
Short, broad, points horizontally (large surface area for muscle attachment)
Facets of articular processes of vertebrae?
Cervical: Oriented at 45° (allows flexion, extension, lateral flexion, and rotation)
Thoracic: Oriented in coronal plane (60°; good for rotation, limited flexion/extension)
Lumbar: Oriented in sagittal plane (good for flexion/extension, limited rotation)
What facets do thoracic have others do not?
Costal facets and demifacets for ribs on coronal plane
What happens to vertebrae after 4 decades?
Density + strength decrease
Vertebral body bows inward (concave)
Osteophytes (bony spurs) try to replace old bone but wrong shape
Resistance training can alter this
How many joints in a motion segment, where are the?
Intervertebral disc between vertebral bodies.
Zygapophyseal joints for superior and inferior articular processes.
What kind of cartilage is zygapophyseal joint?
synovial
What kind of cartilage is Intrevertebral disc?
Symphysis: Secondary cartilaginous
Structure of IV disc?
- Hyaline cartilage end plate:
- transmit weight to adjacent vertebral bodies
- Confines nucleus pulposus and annulus fibrosis to IV disc
- Provide nutrition - Annulus fibrosis:
- Thick outer fibrocartilaginous alternating rings (perpendicular)
- Holds vertebral bodies together - Nucleus pulposus:
- gelatinous
- high fluid
- pressure distribute
- Allow vertebral bodies roll over one another
- Shock absorb
Innervation of IV disc?
1/3 annulus fibrosis innervated
Blood distribution in IV disc?
- mostly avascular
- Blood vessels confined outside of annulus fibrosis
- Get nutrients and remove waste via diffusion through movements
- Limited capacity for healing
How much percentage of length of vertebral column is taken by IV disc?
25-33%
- increase in thickness as you go down
- thickest in cervical and lumbar, greater range of motion
Thicker anteriorly in cervical and lumbar
When you twist the IV disc…
Nucleus being pushed against is strong, but 50% lax on the other side (lost 50% layering)
Differences in AF between vertebrae?
Cervical:
- Distinct, strong, thick anterior, thin nonalternating posterior. Laterally absent (not a full ring)
Thoracic:
- 60% disc volume
- height same anterior rand posterior
- Height of disc smaller than other vertebrae
Lumbar: Highest and widest. Posterior concavity, Posterior lateral not well enforced.
Differences in NP in vertebrae?
Cervical:
- fibrocartilage core
- no gelatin
- uncovertebral clefts (horizontal fissures) penetrate core
Thoracic:
- Slightly posteriorly directed NP
Lumbar:
- Slightly posteriorly directed NP (bit more than thoracic)
What happens to IV disc as you age?
- More fibrous (AF and NP similar)
- NP less water
- AF cracked and hard
- IV also loses height
IV Disc pathologies
- Disc prolapse: Nucleus penetrating annulus
- mostly posterior or posterior lateral (spinal cord there, so may hit)
- Lower cervical and lumbar most affected
What does anterior longitudinal ligament do?
Resists vertical separation (limits extension)
Posterior longitudinal ligament function?
Resist posterior vertebral body separation (flexion)
Ligamentum flava (Paired) function?
Resist separation of laminae (blends with anterior part of zygapophyseal capsule, limits flexion.)
Interspinous function
Resist separation of posterior vertebral bodies like the posterior longitudinal ligament
Supaspinous ligament
Resists separation of the spinous processes , limitss forward flexion
Intertransverse function?
Resists separation of transverse processes, resist lateral flexion
Iliolumbar function?
Resists flexion, extension, rotation and lateral flexion
What is ankylosing spondylitis?
Ossification of AP or supra or interspinous
Characterisics of the craniovertebral joints?
No IV disc (between c1 and c2)
Composes of atlantooccipital joint (between C1 and head)
and Atlanto-axial joint (C1 and C2)
What kind of joint is atlantooccipital?
Synovial, biaxial (F, E, lateral flex)
Atlanto-axial movements and type of joint?
2x lateral: Synovial, glides
1x medial, synovial, uniaxial pivot (30 degree rotation)
What is other names for C1 and C2 vertebrae?
C1 atlas
C2 Axis
Uncovertebral joints are?
C3-C7
Synovial joints developed from uncovertebral clefts in IV discs
Between uncinate process below and above
Increase cervical range of motion
Allow creation of joint for vertebral body above
Ligaments unique to cervical vertebrae?
- Posterior longitudinal ligament (no IV disc, reinforced by it)
- Reaches C2 to become tectorial membrane
- cruciform
- Apical and alar (alar on both sides, apical medial)
What injuries occur because transverse ligament of atlas is stronger than dens of C2?
Dens fracture at the base (avascular necrosis)
What happens when transverse ligament ruptures or become lax?
Incomplete dislocation of the median atlantoaxial joint leading to spinal cord compression
Hyperextension injuries of neck (car crash)
Cervical spondyloysis, , transverse/alar/anterior longitudinal damage, C2/3 IV disc rupture, spinal cord damage
Rebound of head can also dislocation zygapophyseal joints
Forceful hyperflexion of cervical region?
IV disc rupture, body fracture (anterior displacement), z joint displace
