W2: MC Flashcards
What two features make up the intervertebral disc?
- Nucleus pulposus
- Annulus fibrosus
What is the nucleus pulpous?
What does it consist of?
What is its role?
- The central part of the disc
- Gel-like consistency, rich in water and proteoglycans
- Provides elasticity and compressibility, allowing the disc to absorb and redistribute loads
What is the annulus pulposus?
What does it consist of?
How do the outer layers compare to the inner layers?
- Surrounds the nucleus pulposus
- Composed of concentric layers of collagen fibres (arranged in a criss-cross pattern to give the disc strength so it can withstand tensile force).
- Outer layers are denser and more fibrous, while inner layers are more elastic and cartilaginous
Three main roles of the intervertebral discs?
Shock absorption
Mobility and flexibility
Spinal support
What happens to the intervertebral discs during flexion?
- How does the spine bend?
- Front part of the disc is….
- While the back part of the disc is….
- How does this affect the pressure on the anterior vs posterior part of the disc
- Nucleus pulposus tends to move in which direction?
Flexion of the back: spine bends forward, and the front part of the discs is compressed while the back part is stretched.
This movement leads to an increase in pressure on the anterior (front) part of the disc and a decrease in pressure on the posterior (back) part.
The nucleus pulposus, the gel-like center of the disc, tends to move posteriorly.
What happens to the intervertebral discs during extension?
- Spine arches …… and the opposite happens to the….
- anterior part of the disc is ….. while the posterior part is …..
- Nucleus pulposus moves …..
Spine arches backward and the opposite happens to the intervertebral discs
The anterior part of the discs is stretched and the posterior part is compressed
The nucleus pulpous tends to move anteriorly during extension
What happens to the intervertebral discs during rotation?
Puts more pressure/stress on the annulus fibrosus (especially rotation and flexion combined)
What is the most dangerous position for the intervertebral discs?
Rotation with high load (especially flexion and rotation combined)
How does the lumbar vertebrae move during extension?
The posterior elements of the vertebrae (spinous processes, laminae, and facet joints) …… each other. The anterior longitudinal ligament becomes ….., while the posterior ligaments (such as the ligamentum flavum) and intervertebral discs ……
Approximate each other (come closer)
Stretched
Compress
How does the lumbar vertebrae move during flexion?
The facet joints ….. up during flexion, allowing the vertebrae to move apart ……. This opening helps increase the space within the intervertebral …… (the gaps through which spinal nerves exit the spine), reducing potential ….. ……
Open
Posteriorly
Foramina
Nerve compression
How do the lumbar vertebrae move during rotation?
During rotation, the facet joints on the side …… the direction of rotation approximate (come …… together), while those on the same side separate …… The intervertebral discs undergo …… stress during rotation.
Opposite
Closer
Slightly
Torsional
What ligaments of the facet joints are particularly important in resisting excessive rotational movement?
The Capsular ligaments
During lateral flexion, the facet joints on the side of the bending (ipsilateral side) move ….. …… (approximate), while the facet joints on the opposite side (contralateral side) move ….. (gap). The intervertebral discs experience …… forces on the side of the bend and …….. (stretching) forces on the opposite side.
Closer together
Further apart
Compressive
Tensile
Back pain is a symptom or a disease?
Symptom
Back pain is the most common MSK health issue worldwide - true or false?
True
Life time prevalence of back pain is?
Global prevalence of LBP is?
Likelihood of fracture?
Malignancy
70-80%
18.1%
4%
0.7%
The incidence of back pain is higher in males or females?
Females
What age group has the highest incidence of back pain
60-69?