Lumbar, SI, Cervical and TMJ Flashcards
What do spinal curves do and what are they
give spinal column 10x more strength
provide shock absorption and balance of COG
Lumbar and cervical-lordosis
Thoracic and sacrum-kyphotic
vertebral weight
major weight bearing structure
handles compressive loading
vertebral arch
**Posterior** pedicles transverse process articular process articular facet lamina spinous process
- attachment site for muscles and ligaments
- forms ossseous ring that is vertebral canal
facet joints
synovial joints
different orientation in the cervical, thoracic and lumbar spine
FUNCTIONS:
guides movement
limits movement
handles 20-30% of compressive loads
pedicle
connects vertebral body to lamina
laminae
connect pedicle to the spinous process
transverse process and spinous process
serve as ligament and muscle insertion sites
anterior longitudinal ligament
attaches to anterior vertebral bodies and discs
helps limit extension
posterior longitudinal ligament
attaches to posterior vertebral bodiesand discs
helps to limit flexion
ligamentum flavum
helps to limit flexion
forms anterior portion of facet
interspinous ligament
between the spinous processes
helps to limit flexion
intertransverse ligament
between transverse processes
helps to limit sidebending
supraspinous ligament
between tips of the spinous processes
helps to limit flexion
annulus fibrosis
made up of dense layers of collagen fibers and fibrocartilage
fiber orientation changes obliquely from layer to layer giving it tensile strength to resist compression, twisting and bending
fibers of the innermost layer blend with nucleus pulposus
nucleus pulposus
gelatinous mass located centrally in disc
nerve roots
exits below the corresponding vertebral body
spinal cord ends between vertebrae L1 and 2 and extends as Cauda Equina
disc pathology usually affects nerve root below
dermatomes
sensory nerve root distribution
L1-groin
L2-lateral and upper thigh
L3-lateral mid, anterior lower thigh and medial knee
L4-lateral knee, medial lower leg, 1st toe
L5-lateral lower and posterior leg, dorsal foot, 2-4 toes and plantar of 1st toe
S1- lateral foot, plantar foot 2-5 and mid posterior leg
Myotomes
motor nerve root distribution
L1-2: hip flexion L3- knee extension L4- ankle dorsiflexion L5- 1st toe extension S1- ankle plantar flexion
Flexion disc movement
anterior portion of the disc is compressed and nucleus pulposus moves POSTERIORLY
Extension disc movement
posterior portion of disc is compressed and nucleus pulposus moves ANTERIORLY
Lateral Flexion disc movement
nucleus proplsus moves away from the compression= opposite the direction of the bend
disc lesion causes
wear and tear of annular fibers
- repeated flexion or rotational movements
- poor circulation to the disc prevents healing of microtears
- any microtears that do heal are weaker once healed
degenerative changes of nucleus propulsus
- nucleus becomes more fibrotic over time
- less water content as disc ages
traumatic rupture of annular fiber
protrusion
annulus bulges but nucleus is contained within the annulus and supporting structures
only level that can be fixed
extruded
nucleus extends through the annulus, beyond confines of posterior longitudinal ligament or above/below disc space, still in contact with the disc