Thoracolumbar osteology and arthrology - Exam 1 Flashcards
what is the purpose of the osteology of the vertebrae and ribs
provides vertical stability
protects spinal cord
protects ventral and dorsal verve roots and exiting spinal nerve
what are the 3 divisions of the vertebrae
vertebral body
posterior elements
pedicles
what is the purpose of the vertebral body
anterior
primary WB component
what are the posterior elements of the vertebrae
transverse spinous process, laminae, articular process
what are the pedicles of the vertebrae
what are their purposes
bridge that connects body-posterior elements
thick/strong
transfers muscles forces applied to posterior elements for dispersion across the body/disc
what type of shoes would alter the line of gravity throughout the body
how do they change the line of gravity
high heels
put the line of gravity behind the body
what is the overall purpose of the ligaments throughout the spine
limit motion
help maintain natural curves
protect the spinal cord/nerve roots by stabilizing the spine
different strengths and functions
what is the function of the the ligamentous flavum
where is it located
resists end ROM flexion
posterior to spinal cord
where is the interspinous ligament located
between adjacent spinous processes and blends with ligamentum flavum
where is the supraspinous ligament located
between tips of spinous processes
when is the intertransverse ligament taught
contralateral flexion
where does the anterior longitudinal ligament run
what is its function
occiput to scarum
fiber reinforce anterior disc
where does the posterior longitudinal ligament (PLL)
what is its function
C2-sacrum in the canal
blends with and reinforces posterior discs
what is the function of the capsular ligaments
connect facets and stabilize
reinforce by adjacent muscle (multifidus)
t/f
loss of intervertebral stiffness can lead to abnormal and increased intervertebral motion
true
what is the neutral zone
amount of intervertebral movement that occurs with the least passive resistance form the surrounding tissues
what can increase the neutral zone
injury or weakness of surrounding tissues
t/f
marked or chronic instability will not cause further injury
false
what is expected if the neutral zone grows larger as disc degeneration/ligamentous injury occurs
more laxity/instability in the spine
high stress placed on stabilizing systems
how can core stability be viewed
segmental level ad the whole spine level
the neutral zone ____ with injury and degeneration
increase
the neutral zone ____ with muscle force
decreases
how does DDD alter the spine
increases pain and hypermobility of the spine
influences motion of the whole spine
what is the effect of marked/chronic spinal instability
can cause further injury to local ligaments
injury to facets, discs, neural structures
loss of pain free ORM
can be surgical
what is the function of the passive system
what structures are included
sends feedback to the neural subsystem about joint position
challenges to stability at the passive level
bony structures, ligaments, joint capsules, discs, passive portion of musculotendinous units
what structures are included in the active system
muscles and tendons
subject of core exercises
what is the function of the neural subsystem
receives and transmits information from/to active/passive systems to manage spine stability
what patients could have compromised neural subsystem
patients with LBP
must be considered in core stabilization program
describe how T1 and T10-12 are atypical when compared to the other thoracic vertebra
T1: full costal attachment and demi
T10-T12: full costal attachmenti
what plane are the superior/inferior articular facets of the T spine oriented
frontal plane
what are the 3 types of ribs and where are the located
true ribs (1-7)
false ribs (8-10)
floating ribs (11-12)
what is the shape of the vertebral foramen in the thoracic spine
circular
what is the shape of the lumbar vertebrae vertebral foramen
flattened triangle
what section of the spine is the vertebral body the largest
lumbar
how do articular facets of the lumbar region orient
vertically
what joins the 5 segments of the sacrum in children
cartilaginous membrane
fuses by adulthood
what are the 3 functional components of typical intervertebral joints
transverse/spinous processes
apophyseal joints
interbody joint
what is the funciton of the transverse/spinous process
mechanical levers that increase mechanical leverage of muscles and ligaments
what is the function of the apophyseal joints
guiding intervertebral motion
what is the funciton of the interbody/intervertebral joint
absorb and distribute load
highest adhesion between vertebrae
houses axes of rotation
spacer
provides passage for nerves
describe apophyseal joints
lined with articular cartilage
enclosed by synovial capsule
mechanical barricades
what sections of the spine most frequently have small and inconsistently formed accessory structures
upper cervical and lumbar
what 2 structures make up the disc
nucleus pulposus and annulus fibrosis
describe the nucleus pulposus make up
pulplike gel mid to posterior aspect of disk
70-90% water in youth
what is the purpose of the NP of the disc
hydraulic shock absorbing system
dissipates and transfers loads across consecutive vertebrae
gel-like, GAGs
describe the annulus fibrosis
concentric rings of collagen fibers on the outer portion of the disc
prevents distraction/shear/torsion
outer layer contains disc contains sensory nerves only
outer portion binds to ALL and PLL
describe the vertebral end plates
cartilaginous caps over superior/inferior surface of vertebral bodies
binds to AF
limited healing at disc d/t limited blood supply
allows for diffusion of oxygen and glucose
what can cause reduced permeability through the intervertebral disc
degenerative changes
how are intervertebral and apophyseal joints protected from compressive forces
compressive forces produce hydrostatic pressure in disc and evenly distribute load
reduced permeability of the intervertebral disc can cause..
inhibition of proteoglycan syntheses
less proteoglycans = less water
less ability to absorb and transfer loads
what can cause reduced permeability to the disc
excessive/abnormal loads
aging
how does the load sharing system of the IVD work
end plates are pushed toward NP
collagen/elastin rings resist/balance force
viscoelastic
how are IVDs viscoelastic
resist a fast/strongly applied load
less resitance to slow.light compression
flexible with low loads, rigid at high loads
sustained and full lumbar (flexion/extension) reduces pressure in discs and can allow water to be resorbed into the disc
extension
what is spinal coupling
any movement of the spine in a plane is combined with an automatic and imperceptible movement in another plane
what is the normal ROM of throacic flexion/extension
flexion: 30-40
extension: 15-20
total: 45-60
what is the normal ROM of axial rotation
25-35
what is the normal ROM of lateral flexion
25-30
how do ribs move during inspiration
shaft of rib elevates upward and outward
t/f
elevation of the rib increases AP and ML diameters of the throax
true
describe how the rib moves during elevation
head and neck of rib rotate
L1-L4 facets are oriented in what plane
facets are vertical
sagittal plane bias
L5-S1 junction facets are oriented in what plane
frontal plane
___ degrees of lordosis of the lumbar spine
40-50 degrees
what is BWs
shear force of body weight directed parallel to the superior surface of the sacrum
what is BWc
force of body weight directed perpendicular to the superior surface of sacrum
what muscles contract for an anterior tilt of the pelvis
contraction of hip flexors and back extensors
what muscles contract for an posterior tilt of pelvis
contraction of hip extensors and abs
what position would the pelvis rotate when kicking a soccer ball on the kicking leg
posterior tilt
what position would the pelvis rotate when extending a leg back
anterior tilt
what structures resist shear at L5/S1
disc
capsule of facets
ALL
wide and sturdy facets
how many degrees of flexion is normal in the lumbar spine
45-55
how many degrees of exension is normal in the lumbar spine
15-25
how many degrees of axial rotation is normal in the lumbar spine
5-7
how many degrees of lateral flexion is normal in the lumbar spine
20
what plane has dominance in the lumbar spine and why
sagittal plane
sagittal plane orientation of facets
describe the osteokinematics of L3-L4 flexion
inferior facts of L3 slide superior/anterior
superior facet of L4 slides inferior/posterior
flexion of the lumbar spine causes compression on the ___ aspects of the disc and vertebral bodies
anterior
flexion of the lumbar spine causes the NP to move (anterior/posterior)
posterior
describe the arthrokinematics of L3-L4 extension
inferior facet of L3 slides inferior/posterior
superior facet of L4 slides superior/anterior
full lumbar extension causes inferior articular facets to slide ___ beyond he joint surface
inferior
t/f
full lumbar flexion reduces pressure within the disc and reduces contact pressure between disc materials and neural tissue
false
full lumbar extension reduces pressure within the disc and reduces contact pressure between disc materials and neural tissue
in the early phases, trunk extension occurs to a greater extent through extension of the ____
hips
what are some hip extensor muscles
gluteus maximus and hamstrings
in the middle phase, trunk extension occurs through the activation of what 2 muscle groups
hip extensors
lumbar extensors
explain the arthrokinematics of axial rotation of the lumbar spine
ipsilateral facet gaps and capsular stretch
contralateral facet impacts
> __ degrees at any lumbar segment would damage facet surface and tear AF
3 degrees
how many degrees of motion is normal for lateral felxion of the lumbar spine
20 degrees
