Axial Skeleton- "Intro, Function, and Sacral- WK13 ( Ch9+10) Flashcards
What are the primary and secondary curves of the spine ?
Primary: sacral and thoracic kyphoses
Secondary: Lumbar and Cervical Lordoses
What happens to the spinal curves during sagittal plane movement: Cervical Flexion and Extension
Flexion: Decreased Lordosis
Extension: Increased Lordosis
What happens to the spinal curves during sagittal plane movement: Thoracic Flexion and Extension
Flexion: Increased Kyphosis
Extension: Decreased Kyphosis
What happens to the spinal curves during sagittal plane movement: Lumbar Flexion and Extension
Flexion: Decreased Lordosis
Extension: Increased Lordosis
What happens to the spinal curves during sagittal plane movement: Sacral
sacrococcygeal curvature is fixed
What is one negative of having spinal curves ( especially at transitions) ?
The spine becomes subject to shear forces
Where does the line of gravity fall for each spinal curve and is this a good thing or a bad thing ?
Just in front of the curves concavity; This is a good thing (1) it allows for natural maintenance of normal curves (2) alternating flexion and extension torques minimizes NET torque; which minimizes muscle use and ligament stretch.
For each ligament give its attachments, function, and special qualities: Ligamentum Flavum
attch.: superior laminae to inferior laminae
function: form posterior wall of the vertebrocanal, resist flexion
special qualities: highly elastic, “yellow ligament”
For each ligament give its attachments, function, and special qualities: Supraspinous and Interspinous
attch.: between spinous processes
function: resist flexion
special qualities: superiorly becomes ligamentum nuchae, inferiorly becomes more sparsse and partially replaced by TL fascia and small musculotendinous fibers.
For each ligament give its attachments, function, and special qualities:Intertransverse
attch.: extend between adjacent transverse processes
function: resists forward and lateral flexion
special qualities: thin and poorly defined
For each ligament give its attachments, function, and special qualities:ALL
attch.: from basilar part of occipital bone to anterior sacrum
function: resists extension
special qualities: long, strong, straplike, widens caudally
For each ligament give its attachments, function, and special qualities:PLL
attch.: posterior surface of C2 to the sacrum
function: resists flexion
special qualities: cranially broad, inferiorly narrow
For each ligament give its attachments, function, and special qualities: Apophyseal joint capsules
attch.: along the rim of the facet surfaces
function: maintains physical integrity of the joint while guiding spinal kinematics
special qualities: lax in anatomic position; increasingly taut at movement extremes.
What happens to the PLL as it descends through the lumbar spine and how does this affect the discs in the lumbar region ?
- It becomes more narrow as it ascends
- It does not inhibit posterior bulging of the discs.
Describe a motion segment and it’s components:
Transverse and Spinous processes
Facet Joints
Interbody joint, disc
Define the following terminology as it relates to movement at a spinal motion segment: Osteokinematics
movement or rotations within 3 cardinal planes
Define the following terminology as it relates to movement at a spinal motion segment: Arthrokinematics
relative movement between articular surfaces, facet joint movement
Define the following terminology as it relates to movement at a spinal motion segment: Axis of Rotation
using the anterior and superior surface of the vertebral segment
C6 rotation means that the vertebral body rotates to the ____________ but the spinous process rotates to the ____________
right, left
What are “ intra-articular inclusions” and how can they affect facet joints ?
Small and inconsistently formed accessory structures like subcapular fat pads or fibro-adipose meniscoids
- They may act as “ deformable spacers” ; provide protection at extremes of motion; may become impinged and lead to cervical pain; may “lock” or block joints by resisting arthrokinematics.
Which part of the IVD has nerve and blood supply ?
the outer layers of the annulus fibrosus
How does the annulus help dissipate loads ?
The annulus resists radial deformation adding rigidity to gel-like nucleus
How does the disc get its nutrition ?
From vertebral bodies and blood vessels in superficial annulus, nutrients must diffuse to get deeper.
Why are we taller in the morning than in the evening and why would a disc be more painful in the morning ?
- Due to increased disc volume as water re-enters the disc over night
