Exam 1 Flashcards
(131 cards)
Vertebral body function
resist compressive load
Vertebral pedicle function
Transmit the bending forces from the posterior elements to the vertebral body
Vertebral lamina function
Transmit forces from the articular, transverse and spinous processes to the pedicles
Vertebral transverse procress function
Serve as muscle attachment and provide mechanical lever
Vertebral spinous process function
Serve as muscle attachment and provide mechanical lever; may also serve as bony block to motion
Vertebral foramen function
Combined with all segments, forms a passage and protection for the spinal cord
what does an intervertebral disc consist of?
- nucleus pulposus
- anulus fibrous
- vertebral end plate
what is the nucleus pulpous?
- “Pulp-like gel”
- 70-90% water
- jelly part of intervertebral disc
what is the annulus fibrosis?
- Fibrous outer ring
- 60-70% water
- Collagen and elastin arranged in 15 to 25 concentric layers
- Fibers oriented 65° from vertical
- band portion of intervertebral disc
what is the vertebral end plate
- Cartilaginous layer covering superior and inferior surfaces of the disc
- 0.6 to 1 mm of cartilage in adults, larger in children
- Strongly attached to annulus fibrosis but not the vertebral body
- can be apart of the bone
how much of force is transmitted through intervertebral disc?
80%
what in the intervertebral disc is capable of resisting distraction, shear, and torsion
anulus fibrosis
anterior longitudinal ligament
limits extension
- reinforces anterolateral portion of annulus fibrosis and anterior aspect of intervertebral joints
posterior longitudinal ligament
limits forward flexion
- reinforces posterior portion of anulus fibrosis
ligamentum flavum function
limits forward flexion
- particularly in lumbar area
interspinous ligaments
limits forward flexion
supraspinous ligaments
limits forward flexion
intertransverse ligaments
limits contralateral lateral flexion
what is coupling
consistent association of one motion about an axis with another motion around a different axis
coupling patterns vary based on…
- spinal structure
- spinal curvature
- orientation of articulating facets
- fluidity/elasticity/thickness of the disc
- extensibility of the muscles, ligaments, joint capsules
what do the inter body joints do
- determine magnitude of movement
- distribute load
- create space for movement and passage of spinal nerve roots
what do facet joints do
- determine direction of movement
2. influenced by geometry, height, and spatial disorientation
vertebral flexion is…
anterior tilt and anterior glide of superior vertebra
vertebral flexion results in ..
- widening of intervertebral foramen
- separation of spinous processes