lecture 12: lumbar Flashcards
how many lumbar vert are there
5
what are the spinal curves
cervical lordosis
thoracic kyphosis
lumbar lordosis
does the cervical curve go anterior or posterior
is it kyphotic or lordotic
goes anterior
lordosis
does the thoracic curve go anterior or posterior
is it kyphotic or lordotic
posterior
kyphotic
does the lumbar curve go anterior or posterior
is it kyphotic or lordotic
anterior
lordotic
anterior means lordotic or kyphotic
lordotic
what are the articular processes
the facet joints is where the vert articulate with each other
why is the lumbar vert body larger
more weight bearing
what are the 2 main functions of the lumbar ligaments
restrain movement
sensory- provide information about vert postition
anterior spine ligaments prevent what movment
extension
posterior spine ligmanets prevent what movement
flexion
what bony articulations make up the facet joints
superior and inferior articular process
where does the majority of the movement of the spine occur
at the facet joints
what makes up the intervertebral joint
vert bodies
intervertebral disc
true or false: the facet joints are synovial joints
truw
is there increase loading on the facets with extension ro flexion
extension
during extension, is there increase or decrease loading on the facet joints
increase (getting compression)
during flexion, is there increase or decrease loading on the facet joints
decrease (opening up)
what is the 4 functions of the facet joints
guide segmental motion
resist anterior shear
resist torsion
resist compression
what are the 4 functions of the intervertebral joints
maintain space between vert
allow movement
resist compression
resist rotation
how do the intervertebral joints resist compression
because of shock absorption
what helps the spinal n and structures not get compressed
intervertebral joints
true or false: there is not a lot of rotation at the lumbar joint
true
what makes up the outer portion of the intervertebral joint
annulus fibrosis
what material makes up the annulus fibrosis
fibrocartilage
what is the orientation of the annulus fibrosis
obliquely oriented (fibres go in opposite direction)
what does the annulus fibrosis resist
tensile force and compression
what is the inner portion of the intervertebral disc
nucleus polpusos
what is the nucleus polposus made of
70-90% water (fluctuates)
what is the function of the nucleus poplusus
resist compression
role in nutrition
what are the 3 translation of the lumbar movement
distraction/compression
anterior/posterior shear
left/right shear
what movements would cause compression of lumbar
squation
what movements would cause distraction of lumbar
hanging from arms
what movement would cause anterior/psoteruor shea=r
trauma ex: car accident
what are the 3 rotations of the lumbar movement
flexion/extension
left/right sideband (lateral flex)
left/right rotation
true or false: lumbar facet joints are more parallel to saigtal plane than thoracic facets
true
lumbar facet joints are more parallel to BLANK plane than thoracic facets
sagitall plane
the lumbar orientation of the facet joints allows what movements and limits which
allows flexion/extension
limits rotations and lateral flexion
the thoracic vert is more parallel to what plaen
frontal plane (allows more rotation)
the lumbar vert is more parallel to what plane
lumbar (allows more flexion)
what is the lumbar flexion ROM
35-52
what is the lumbar extension ROM
15-29
what is the lumbar sidebend/lateral flex ROM
16-25
what is the lumbar rotation ROM
5-16
where is the most rotation located
at the neck cervical (c1-c2)
as you get closer to lumbar, what happens to rotation
decrases
as you get closer to lumbar what happens to flexion/extension
icnreases
true or false: the nucleus polposus moves with lumbar movement
true
during lumbar flexion, the nucleus polposus migrates posterior or anterior
posterior
during lumbar extension, the nucleus polposus migrates posterior or anterior
anterior
as you flex your lumbar spine, it comprises your disk anterior, where does the nucleus move
posterior
what is the lumbopelvic rhythm
interplay between lumbar spine and pelvis when movement
to touch your toes, what is the movement of the spine and pelvis
lumbar spine flexes and pelvis anterior rotates
how do tight hamstrings impact the lumbopelvic rhythem
hamstrings attach to ischial tub (on pelvis) so tight hamstrings will pull the pelvis posterior
rotation at the lumbar spine are limited by what 2 things
1) annulus fibrosis (since the different fibre direction)
2) facet joints limit that rotation
when do the facet joints offer less protection to rotation
while in flexion
what is the most vulnerable spine position
flexed and rotated
explain compression of the lumbar spine
hoop stres
vertical load (compression) is converted to circumferential tensile
compression tension in the lumbar spine is resisted by what
annulus fibrosis and vertebral end plates
what are the lumbar joint reaction forces
shear and compression forces
forces on the vert is due to what
gravity on trunk, loading in arms, and muscles/ligaments
there is increase loading on facets with flexion or extnsion
extension
what is another name for spondylolysis
scotty dog fracture
what is spondylolysis
pars interarticularis (b/w sup and inf facet)
what is spondylolysis due to
large magnitude anterior shear (>2000N)
due to repetitive lumbar extension and rotation
what are some sports that cause spondylolysis
sports that are more upright vertically loaded
throwing in track
gymnastics
weightlifting
rowing
understand spondylolysis as Scottie dog fracutre
spondylolysis can result in what
spondylolisthesis
what is spondylolisthesis
anterior displacement of a vertebrae
where does disc herniation usually occur
posterior-lateral
why does disc herniation occur more posterior and lateral
1) annulus fibrosis is thinner in that spot
2) posterior ligs dont run posterior lat (do not protect that spot)
what can disc herniation cause
can impinge on nerve root
-weakness
radiating pain
sensory changes
disc herniation is when what protrudes out
nucleus polposus
when is disc herniation usually occur
injured near the end range of motion (does not have to be high load)
why is disc herniation more common in middle aged adults
they have higher water content (more ability for it to herniate out)
lower water content in older adults
disc herniation is associated with what
repetitive bending
which movement would you want to discourage with posterior lateral lumbar disc herniation
limit flexion since it pushes the n.p posteriorly
what is the intradiscal pressure during lying supine
250 N
what is the intradiscal pressure during standing
500N
what is the intradiscal pressure during coughing
700N
what is the intradiscal pressure during forward bending
1000N
what is the intradiscal pressure during lifting 23 lbs
1700 N
what position caused the highest intradiscal pressure
sitting slouched
what is osteoporosis
lose of bone mass (bone mineral density)
true or false: osteoporosis affects 100 million people worldwide
true
when is osteoporosis more common
frequently after menopause in women
due to osteoporosis, what is the prevalence of vertebral body compression fractures in women
less than 60: 3-17%
greater than 70: 19-46
due to osteoporosis, what is the prevalence of vertebral body compression fractures in men
less than 65: 2-8
greater than 75: 15-21
is osteoporosis more common in men or women
women
what are common areas of vert body compression fractures
thoracolumbar junction and mid thoracic spine
looking at a stress;/strain curve of the femur, what is the relationship of ultimate failure
failure point occurs later in normal ppl than osteroporotic
true or false: when you sit, you are subject to creep
yes because there is a constant load and increase in tissue deformation when sittign
prolonged flexion (slouched sitting) results i nwhat
slow lengthening of lumbar ligaments (increased range of motion) = impaired ligament sensory function
=altered muscle activation
what were the results of sit/stand desks in the graves 2015 group
sit stand desk reduces sitting time by 80 mins/workday in health people
no change in body discomfrot
what were the results of sit/stand desks in the agarwal 2018 group
sit stand desk reduced body discomfort (less than 1 out of 10) in healthy people
what were the results of sit/stand desks in the barony gibbers 2018
sit stand desk reduced disability but not pain in patients with low back pain
what is the risk of stoop lifting with flexed spine
greater anterior shear forces
greater load on ligaments
what is the benefit of squat lifting with neutral spine
muscles provide a posterior shear force to limit the anterior shear
true or false: there is less shearing force when using stoop lifting
false, less when squatting
true or false: educating on lifting is useful
false
no evidence that lifting education can decrease injuries from lifting
during compression, what tissues are loaded
vertebra body and disc muscles
during compression, what is the common injury
vert body or end plate fracture
during roation/side bend, what is the tissue loaded
facet, pedicles, muscles
during roation/sidebend, what is the common injury
pars interarticularis or pedicle fracture
during flexion, what is the tissues loaded
posterior ligaments, posterior annulus fibrosis, fascia, muscles
during flexion, what is the common back injury
annular tear, disk herniation, muscle injury
during spine extension, what is the tissues loaded
anterior ligaments, posterior body elements, muscles
during spine extension, what is the common injury
pars interarticularis fracture,
spondylolisthesis
how do you prevent back injuries
avoid repeated or prolonged end range lumbar flexion
vary positions and loads
allow time for tissues to restore normal length after prolonged loads
do not sit too long
keep loads close
what is cumulative loading
additive effect of shear and impressive forces
considers the magnitude of loading (eg: peak forces or moment) and the frequency of loading)
explain the study of peak force/moments and cumulative loading on predicting injuries in autowrokers
peak shear and compression higher in workers that had a previous lumbar injury
cummularitve shear and compressive higher in workers that had a previous lumbar injury
cumulative load predicted development of low back pain in workers