Lecture 13 - Spine Flashcards
How many primary curves do newborns have in their spine?
1
What are the 2 spine curves?
lordosis and kyphosis
Lordosis involves what 2 spinal segments?
cervical and lumbar
Kyphosis involves what 2 spinal segments?
thoracic and sacral
What are the 2 parts of the structure of the vertebrae?
vertebral body
neural arch
Is the vertebral body the anterior or posterior portion of the vertebrae?
anterior
What kind of loads does the vertebral body sustain?
compressive loads
What kind of bone is the vertebral body made of?
cancellous bone
What kind of vertebral endpoints does the vertebral body have?
cartilaginous vertebral endpoints
What kind of bony ring is the neural arch?
protective
What does the neural arch have?
processes
What boundary do the laminae form of the neural arch?
posterior
What do the laminae shunt forces between? (2 processes)
the spinous processes and the articular processes
What do laminae resist?
rotation
What plane do laminae resist rotation?
transverse plane
What do the pedicles bind the neural arch to?
the vertebral body
What kind of bone are the pedicles composed of?
strong cortical bone
What 2 kinds of loads do pedicles sustain?
high compressive and tensile loads
What direction does the inferior articular process project?
downward
What side does the inferior articular process provide article surface on?
lateral side
What does the inferior articular process articulate with?
superior articular process
Does the inferior articular process articular with the superior articular process of the vertebrae below or above it?
below
Does the superior articular process project upward or downward?
upward
Is the superior articular process smaller or bigger than the inferior articular process?
bigger
What does the superior articular process articulate with?
the inferior articular process of the vertebrae above it
Is the spinous process thick or thin?
thick
What process is the point of attachment of ligaments and muscles?
the spinous process
What is the shape of the transverse process?
long and flat
What process is the point of attachment for structures providing frontal plane stability?
the transverse process
What foramina forms the spinal canal?
vertebral foramina
What disks form the spinal canal?
the intervertebral disk
What do the posterior and transverse processes differ in (2)?
length, orientation
What do facets differ in?
orientation
What do ligaments restrain?
movement
What do ligaments provide information about?
vertebrae position
What 2 structures provide integral support and selected flexibility to the collective vertebral column?
ligaments and fascia
What is the principle of “tensegrity”
system of isolated components under compression within a network of cords under constant tension
What 3 things does the principle of “tensegrity” help maintain?
- structural integrity
- mechanical stability
- optimize loading
What are the 2 facet joints?
superior and inferior articular process
What are the 2 intervertebral joints?
vertebral bodies and intervertebral discs
What kind of joints are facet joints?
synovial
How can you increase loading on facet?
extension
What are the 4 functions of facet joints?
- guide segmental motion
- resist anterior shear
- resist torsion
- resist compression
What are the 4 functions of intervertebral joints?
- maintain space between vertebrae
- allow movement
- resist compression
- resist rotation
What are the 2 parts of the intervertebral disc
annulus fibrosus and nucleus pulposus
What portion of the intervertebral disc does the annulus fibrosus form?
outer portion
What are the rings of the annulus fibrosus made of?
fibrocartilage
How are the rings of the annulus fibrosus oriented?
obliquely
What does the annulus fibrosus resist (2)?
tensile forces and compression
What is found in the annulus fibrosus?
mechanoreceptors and free nerve endings
What portion of the intervertebral disc does the nucleus pulposus form?
the inner portion
What makes up 70-90% of the nucleus pulposus?
water
What does the nucleus pulposus resist?
compression
Where does the nucleus pulposus play a role?
nutrition
What are the 3 translations?
- distraction/compression
- anterior/posterior shear
- left/right shear (glide)
What are the 3 rotations?
- flexion/extension
- left/right side bend (side flexion/lateral flexion)
- left/right rotation (transverse plane)
What 3 parts make up a functional spinal unit?
vertebrae + intervertebral disc + vertebrae
How many vertebrae are in the lumbar segment?
5
What is found anterior and posterior of the lumbar spine?
anterior: intervertebral disc
posterior: facet joint
Lumbar facet joints are more ___ to sagittal plane than thoracic facets.
parallel
What does lumbar movement allow and limit?
allow: flexion and extension
limits: rotations and sideflexion
What are instantaneous centres of rotation (ICR)?
point of rotation for the spine is not fixed in space
At any one time, the centre of rotation can ___.
change
What has implications for clinical treatment?
ICR
What levels of flexion and extension does the lumbar spine have?
high levels
What does the thorax have more of than the lumbar spine?
rotation
Where on the cervical spine is there lots of rotation?
C1-C2
What moves with lumbar movement?
nucleus pulposus
What kind of migration is lumbar flexion?
posterior migration
What kind of migration is lumbar extension?
anterior migration
When bending, some axial ___ will also naturally occur.
rotation
What creates coupled motions during bending?
tension with other elements
To maintain balance, what does the spinal column move in relation to?
the pelvis
What kind of tilt causes natural hyperextension of lumbar spine?
anterior tilt of pelvis
What kind of tilt causes forward flexion of lumbar spine?
posterior tilt of pelvis
Lumbar pelvic rhythm + hip flexion allows for more ___.
ROM
What part of the intervertebral disc resists rotation?
annulus fibrosus
What limits rotation but provides less protection while in flexion?
facet joints
What is compression converted to?
circumferential tension
What 2 structures resist tension?
annulus fibrosus and vertebral end plates
What do torso muscles do to motion rather than try to move a body part?
stop/control
What is the primary role of spine muscles?
create stability
A spine with no muscles ___ under light loads.
bucles
The spine musculature acts as “___” to stiffen the structure.
guy wires
What kind of spine can resist buckling?
stiff spine
What are the 3 extensors of the spine?
- longissimus
- iliocostalis
- multifidus
What are the 3 functions of the spine extensors?
- trunk extension
- spine stability
- leg speed enhancement
What are the 4 abdominal muscles?
- rectus abdominis
- external oblique
- internal oblique
- transversus abdominis
What is the primary function of the abdominal muscles?
trunk flexion
What are the 3 roles of the rectus abdominis?
- trunk flexion
- rib depression
- spine stability
What are the 5 functions of the external obliques?
- trunk flexion
- contralateral trunk rotation
- increases intra-abdominal pressure
- rib depression
- spinal stabilization
What are the 6 functions of the internal obliques?
- Trunk flexion
- Ipsilateral trunk rotation
- Increase intra- abdominal pressure
- Rib depression
- Spinal
stabilization - Defecation, childbirth
What are the 2 functions of the transverse abdominis?
- Increase intra- abdominal pressure
- Spinal stabilization
What are 4 spine musculature exercises?
- bird dog
- side plank
- curl-up
T or F?
Those who have never had a previous back injury appear to have no additional benefit from wearing a belt.
true
Are lifting belts recommended for routine exercise participation?
no
What are the 2 lumbar joint reaction forces?
shear and compression forces
What can go into the body to bridge between healthy bone structures?
prosthetic implants
What do prosthetic implants have to measure the force being applied?
sensors
What happens to COM during obesity?
projected anteriorly
What do static pressure vary with?
posture
What is placed into the vertebral discs to read pressure during different activities?
needled pressure sensors
As incline is increased, IVD pressure ___.
decreases
