Intro to Vertebral Column Flashcards
What is the function of the vertebral column?
It is required to meet the demands of mobility and stability of the trunk and extremities and protect the spinal cord.
What are the 2 primary/kyphotic curves?
Thoracic and sacral
What are the 2 secondary/lordotic curves?
Cervical and lumbar
What is the advantage of a curved vertebral column?
Increased ability to resist compressive loads.
What is a motion segment and what does it consist of?
The functional unit of the spine.
Consist of:
- any 2 adjacent vertebrae
- intervertebral disc
- soft tissue that secures them
What does the typical vertebrae consist of?
Consist of 2 parts:
- Anteriorly = vertebral body
- Posteriorly = vertebral arch
What is the composition of a typical vertebrae?
Shell = cortical bone Interior = cancellous bone/trabecular bone
What is considered the weight bearing structure of the spinal column?
The vertebral body.
What is the function of the pedicles for the vertebral arch?
To transmit tension and bending forces from posterior elements to vertebral body.
What is included in the posterior elements of the vertebral arch?
- Articular processes = 2 superior and 2 inferior facets. Form the articular pillar
- Laminae = pars interarticularis, which is a portion of laminae between superior and inferior articular processes. They are subject to bending forces.
- Spinous process
- Transverse process
Describe the general function of each segment that makes up a vertebrae.
- Body = resist compressive loads
- Pedicle = transmit the bending forces from the posterior elements to the vertebral body
- Lamina = transmit forces from the articular, transverse and spinous processes to the pedicles
- Transverse processes = serve as muscle attachment and provide mechanical lever.
- Spinous processes = serve as muscle attachment and provide mechanical lever; may also serve as bony block to motion.
- Vertebral foramen = combined with all segments. forms a passage and protection for the spinal cord.
Describe the intervertebral disc and what it consist of
Composes 20-33% of vertebral height and progresses in size as go down the spinal column.
Consist of:
- nucleus pulposus
- Anulus fibrosus
- Vertebral end plate
What is the nucleus pulposus?
Pulp-like gel in the center of the disc.
70-90% water
What is the annulus fibrosus?
The fibrous outer ring of the disc.
60-70% water and is composed of collagen and elastin.
Arranged in 15 to 25 concentric layers/rings and the fibers are oriented 65 degrees from vertical.
What is the vertebral end plate?
The cartilaginous layer.
Covers the superior and inferior surfaces.
Strongly attached to annulus fibrosis but no the vertebral body.
What is the function of the intervertebral disc?
- Separate two vertebral bodies and therefore increase available motion.
- Transmit load from one vertebral body to the next.
- Stabilization of the spine.
- Provide space between vertebrae for exiting spinal nerves.
Describe what an intervertebral joint is and the type of motion they provide.
A joint between the vertebral bodies.
Motion:
- gliding
- distraction and compression
- rotation/tilt