Lumbar Spine (Part 1) Flashcards
__% of persons in industrialized countries will have LBP at some point in their lives
70
What is the peak prevalence of LBP?
35-55 years old
90% of patients with acute LBP self-resolve within _ weeks
6
What percentage of LBP patients develop chronic pain?
2-7%
About _% of people seen with LBP in primary care have compression fractures
4
About _% of people seen with LBP in primary care have a neoplasm
1
What is the prevalence of a prolapsed IVD?
1-3%
The lumbar spine can flex __-__ degrees
50-70
The lumbar spine can extend __-__ degrees
10-30
The lumbar spine can rotate __-__ degrees
20-40
The lumbar spine can side-bend __ degrees
25-35
During 85 degrees of TL flexion, __ degrees are due to thoracic flexion and __ degrees are due to lumbar flexion
35
50
During 35-40 degrees of TL extension, __-__ degrees are due to thoracic extension and __ degrees are due to lumbar extension
20-25
15
During 40 degrees of TL rotation, __ degrees are due to thoracic rotation and __ degrees are due to lumbar rotation
35
5
During 450 degrees of TL side-bending, __ degrees are due to thoracic side-bending and __ degrees are due to lumbar side-bending
25
20
How do end plate fractures occur?
During extreme compressive loading the end plates bulge into the vertebral bodies causing radial stresses and fracture occur
What occurs in the end plate fractures are large enough?
the liquid nucleus pulposus squirts through the end plate into the vertebral body
When local areas of bone collapses under the end plate creating a pit or crater what is gradually formed?
a Schmorl’s node
Schmorl’s nodes are associated with spinal compression with the spine in what position?
neutral
Does the annulus fibrosis remain intact with end plate fractures?
Yes
Why are end plate fractures often misdiagnosed as true herniations?
Following the loss of the nucleus from the disc into the vertebral body there is an immediate loss of disc height and a compromise of the nerve root results mimicking the symptoms of true herniation
What does failure of the posterior elements of the spine lead to?
spondylolisthesis
True or False
The neural arch (pedicles and laminae) are somewhat flexible during flexion and extension movements
True
In athletes such as gymnasts, the damage to posterior elements may be associated with what type of ROM?
full
In patients with a pars fracture (spondylolisthesis) what is the focus of therapy?
stability
The fibers of the annulus fibrosis are oriented in an alternating fashion __ degrees from the vertical
60
What are the 3 major components of the IVD?
- nucleus pulposus
- annulus fibrosis
- end plates
Even though there is no distinct border between the NP and AF, how can you tell the differences between the 2 structures?
The lamellae of the annulus become more distinct moving radially outward
Describe why only half of the fibers of the AF are able to support twisting motions while the other half are disabled
Due to the orientation of the fibers
What direction does the annulus bulge when there is little hydrostatic pressure (end plate fracture or herniation) during compression?
outer annulus bulges outward
inner annulus bulges inward
What does the double convex bulging associated with end plate fractures cause?
The laminae of the AF to separate or delaminate
What does this delamination lead to?
Leaking of nuclear material through the lamellae layers and finally extrude, creating a frank herniated disc
IVDs must be bent to ___ ROM in order to herniate
full
In what types of occupations is herniation linked to?
Those that are sedentary, require sitting posture, and vibratory