Intro to Vert. Column Flashcards
Where are the two primary kyphotic curves located?
Thoracic
Sacral
Where are the two secondary lordotic curves located?
Cervical
Lumbar
What is the benefit of these curves over a stacked column? What is the drawback?
Benefit - increased ability to resist compressive loads
Drawback - shear forces to act in regions of transitions between curves
Describe the composition of vertebrae that allow for them to be light yet weight bearing
Shell - cortical bone
Interior - cancellous bone
What is the role of the vertebral body?
Weight-bearing
What is the role of the pedicles?
Transmits tension and bending forces from posterior elements to vertebral body (increase in size as you go down in the column to handle more forces)
What is the role of the laminae?
Transmit forces from articular, transverse ands spinous processes to pedicles
What is the role of the articular facet processes?
- 2 superior facets and 2 inferior facets
- Form the articular pillar (all facet joints together)
If someone has a pars interarticularis fracture where is that fracture?
-Between superior and inferior processes
If they have a bilateral pars interarticularis fracture what concerns do you have?
Where will you most commonly see it and in what athlete?
- Stress fracture occurs bilaterally resulting in forward slipping of the vertebra know as spondylolosthesis
- Most commonly L5/S1 segement
- Will often see in gymnasts
What is the role of the spinous process?
- Serve as muscle attachment and provide mechanical lever
- Also serve as bony block to motion
What is the purpose of the intervertebral discs?
- Separate 2 vertebral bodies and increase available ROM (Cervical motion due to ratio of disk>than body)
- Transmit load (Lumbar has thicker disk because carrying more load)
- Stabilizes spine (anulus fibrosus capable of resisting distraction, shear and torsion)
- Provide space between vertebrae for exiting spinal nerves
What are the components of the intervertebral discs?
- Anulus fibrosus - keeps nucleus pulposus in center
- Nucleus pulposus
- Vertebral end plate - cartilaginous layer covering superior and inferior surfaces of disc (strongly attached to annulus fibrosus but not vertebral body)
What position increases the pressure on the disc the most? The least?
- Disc pressure large when holding load in front of you with forward bending
- Lifting load with knees flexed places less pressure on discs than with knees straight
- Slouching > disc pressure than sitting erect
What makes up the intervertebral joints?
Superior vert
Inf vert
Vert disc
What makes up the zygapophyseal (facet) joints?
Superior articulating facets
Inferior articulating facet
What structures limit what motions at the spine? (6 lig)
- Anterior longitudinal lig
- Post LL
- Ligamentum flavum (limit forward flex)
- Interspinous lig (limit forward flex)
- Surpraspinous lig (limit forward flex)
- Intertransverse lig (limit lateral flexion)
What is coupling?
Consisten association of one motion about an axis with another motion around a different axis
What is the purpose of coupled motions at the spine? Give an example of a coupled motion?
- To increase ROM
- Lateral flex and rotation
What influences the coupling patterns?
- Spinal posture
- Spinal curvature
- Orientation of articulating facets
- Fluidity/elasticity/thickness of discs
- Extensibility of muscles, lig and joint capsule
What occurs osteokinematically at the spine?
Flex/ext
Lateral flex
Rotation
What is role of zygopohphyseal joints?
- Determine direction of movement
- Thoracic - coronal, favor lateral flex
- Lumbar - sagittal, favor flex/ext
What are the arthrokinematics motions that occur at the intervertebral joints with each of the osteokinematic motions?
- Approximation/distraction
- Gliding/Sliding
- Tipping
What arthrokinematically occurs at the facet joints with the osteokineamtic movements?
- Approximate/gapping (flex/ext)
- Gliding/sliding (lateral flex)
