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?
What is the natural prognosis of back pain?
Natural history of LBP is positive with most patients (60%) with acute pain improves by itself within ~6 weeks. But those with persistent LBP tend to have symptoms for over a year (pain will flare up and settle in between this time)
Disorders are easier to help when….
- There is a strong relationship between symptoms and movement
- Helpful thoughts and behaviours
- Minimal barriers to recovery
- Previously favourable experience with physiotherapy
- Good self-efficacy and locus of control
- Realistic expectations for recovery correspond with the natural history
What are the risk factors for LBP?
- Heavy and frequent lifting (> 25kg)
- Obesity
- Smoking
- Depressive symptoms
(increase risk just moderately - there is no consistent risk factor for first time LBP)
- …..% of patients with acute LBP had atleast one red flag present, yet fewer than ….% had a medically serious condition
80%
1%
Main red flags to look for?
Fracture 4%
Malignancy 0.7%
Cauda equina syndrome 0.08%
Infection 0.01%
What is non-specific low back pain?
- The patho-anatomical cause of the pain cannot be determined
How is non-specific pain stratified?
By symptom duration (acute/subacute = < 12 weeks & chronic = > 12 weeks)
What are two common tools used in predicting outcomes for LBP
STarT back & Orebro musculoskeletal pain screening questionnaire
Article: can screening instruments accurately determine poor outcome risk in adults with recent onset LBP?
Conclusion: LBP screening instruments administered in primary care perform poorly at assigning higher risk scores to individuals who develop chronic pain than to those who do not.
What are the three main outcome measures we should focus on in LBP?
Pain intensity
Function
Health-related quality of life
Others include: work interference, psychosocial function & pain impact
Saddle anaesthsia is generally associated with dysfunction of what vertebrae?
Below S1 (S1, S2, S3?)
What are the muscle groups associated with each nerve root?
L2
L3
L4
L5
S1
S2
- L2: hip flexion – lift your shoe
- L3: knee ext – extend the knee
- L4: dorsiflexion – stop the door
- L5: big toe ext – toes divide
- S1: PF – can lift a tonne
- S2: knee flex – your foot comes back to you
What is involved in neuro screening for LBP?
Babinski response
Ankle clonus
Dermatomes
Reflexes
In LBP what do we observe for?
- Attitude
- Gait
- Overall posture
- Skin markings
- Deformity
In the biering sorrenson test what is considered normal?
2-4 mins = normal
> 2 mins lack of endurance
> 1 min deficit
What is lumbar stenosis?
Narrowing of the lumbar spinal canal which compresses the nerves travelling through the lower back into the legs
Symptoms of lumbar stenosis (Cook clinical decision rule)?
- Age more than 48 years,
- Bilateral symptoms
- Leg pain more than back pain
- Pain during walking/standing,
- Pain relief upon sitting At least 3/5 positive
What aggravates vs relieves lumbar stenosis?
Aggravated by longer walking and released by sitting or flexing
Facet/disc/sacroiliac joint pain - Revel’s criteria?
- Age over 65 years
- Forward flexion
- Extension
- Pain well relieved by recumbency (lying down ie sleeping)
- No exacerbation of pain with coughing and sneezing
- Rising from flexion and the extension rotation test –> 5-7 positive
**study found the criteria is unsuitable as a clinical screening test to select chronic LBP patients for initial ZJ blocks. However the criteria may have use in identiffying a small subset of patients (11%) likely to respond to the initial treatment
Revels criteria for facet joint pain - Specificity and sensitivty?
Sensitivity 0.11 and 1.00
Specificity 0.66 and 0.91
What are the stages of disc herniation?
- Disc degeneration (or desiccation)
- Disc prolapse (or bulge)
- Disc extrusion (or herniation)
- Disc sequestration
What is disc degeneration & what are the symptoms?
This is the earliest stage where the intervertebral discs start to degenerate or dry out due to aging or repetitive stress. The disc may lose its flexibility and become more susceptible to injury.
Symptoms: Often, there may be no symptoms at this stage, or there may be mild back pain.
What is disc prolapse and what are the symptoms?
In this stage, the outer fibers of the intervertebral disc, called the annulus fibrosus, weaken, but the inner gel-like nucleus pulposus remains contained within the annulus. The disc bulges out but does not rupture.
Symptoms: Patients may experience mild to moderate back pain and stiffness. There can be occasional nerve symptoms if the bulge presses on nearby nerves
What is disc extrusion and what are the symptoms?
The nucleus pulposus breaks through the annulus fibrosus but remains within the disc’s outer layers. This is often referred to as a herniated disc. The herniated material can press on spinal nerves or the spinal cord.
Symptoms: More pronounced pain, possibly radiating along the nerve affected (e.g., sciatica in the case of lumbar herniation), numbness, tingling, and weakness in the limbs.
What is sequestration and what are the symptoms?
In this most severe stage, the nucleus pulposus breaks through the annulus fibrosus completely and fragments off into the spinal canal. These fragments can cause severe nerve compression.
Symptoms: Intense pain, significant neurological deficits (e.g., severe sciatica, loss of bladder/bowel control in cauda equina syndrome), and possible muscle atrophy due to prolonged nerve compression
What is the general consensus of LBP versus imaging?
Imaging findings don’t generally correlated with the level of pain
eg 52% of 30 year olds have some level of disgeneration & 96% of 80 year olds
Diagnostic accuracy of imaging for lumbar disc herniation in adults with LBP or sciatic is unknown - what were the findings from this study?
- MRI: Low certainty evidence
- CT: moderate certainty evidence
MRI in sciatica?
No difference between people with and without complaints.
