Define a functional spinal unit (FSU).
Three joints: 2 vertebral bodies connected by an intervertebral disc
What vertebrae are not considered a FSU?
C1-2 as there is no vertebral disc present
Describe the allowable movement of the cervical spine.
Flex, ext, side bend, rotation
Describe the allowable movement of the thoracic spine.
Flex, ext, side bend, rotation
Describe the allowable movement of the lumbar spine.
flexion/ext is greatest; rotation is limited
What is the least mobile segment of the spine?
Thoracic spine
What is the most mobile segment of the spine?
Cervical spine
What 3 things make up the stabilizing system of the spine?
- Active subsystem (spinal muscles and tendons; thoracolumbar fascia)
- Passive subsystem (intervertebral disc, ligaments, facet joints and capsules, vertebrae and passive muscle support
- Neural control system (nerves and central nervous system)
Functional instability versus structural or mechanical instability
Func instability: May cause pain despite the absence of any radio logical anomaly
Structural: May be defined as the disruption of passive stabilizers
What is included in the anterior column of the spine?
Anterior longitudinal ligament (ALL),
anterior annulus,
anterior 2/3 vertebral body
What is included in the middle column of the spine?
Posterior longitudinal ligament (PLL),
posterior annulus,
posterior 1/3 vertebral body
What is included in the posterior column of the spine?
Posterior elements: pedicles, facets, lamina, spinous process
Ligamentum flavum,
Supraspinous lig
What are the three questions orthotists need to ask to determine the best spinal orthosis?
- Which level needs to be stabilized?
- Which plane of motion needs to be restricted?
- How much stabilization is needed?
