Lumbar spine clinical conditions Flashcards
What is the centre of gravity?
Weight of body projected into lower limbs
about a line that passes centrally through natural curvatures of spine
What is the centre of gravity in the vertebral column?
C1, C2
C7, T1
T12, L1
L5, S1
What is senile kyphosis?
Refers to secondary curvatures disappearing
primary curvature re-appearing
with old age
What is an example of an abnormal curvature that is physiological?
Exaggeration of lordosis
of lumber spine
during pregnancy
What is a suitable vertebral level for a lumbar puncture? Why?
L2/L3
L3/L4
L4/L5
After conus medullaris
only have spinal roots, not cord, least chance of neurological damage
What structures does the needle pass through in a lumbar puncture in order to reach the CSF?
Skin Subcutaneous tissue Supraspinous ligament Interpsinous ligament Ligamentum flavum Epideral fat and veins Dura matter Arachnoid matter Subarachnoid space
Not having lower back pain - is it normal or abnormal?
Abnormal
What are the exacerbating factors of mechanical back pain?
When spine is bearing weight e.g. standing, sitting
Exercising
What are the relieving factors of mechanical back pain?
Lying down
Rest
How long does mechanical back pain last?
Intermittent - comes and goes
What triggers mechanical back pain?
Normal activity
e.g. bending down to pick something up
What predisposes to mechanical back pain?
Obesity
Deconditioned core muscles - muscles have to work harder to maintian posture
What is disc degeneration?
Nucleus polposus dehydrates with age
How does disc degeneration affect height?
Height of disc decreases
What are the results of a decrease in disc height?
Reactive marginal osteophytosis
Increased stress placed on facet joints
Leads to osteoarthritis
Pain via meningeal nerve
Decreased size of intervertebral foramen
Compression of spinal nerves
What does spondylosis deformans mean?
Spondylosis = degeneration of vertebral column Deformans = deform
What does senile ankylosis mean?
Senile = old age Ankylosis = abnormal fusion of bones of a joint, giving stiffness
What do young discs look like on an MRI scan?
Appear white
What do degerated discs look like on an MRI scan?
Appear grey/black
What are the four stages of a slipped disc?
Disc degeneration
Prolapse
Extrusion
Sequestration
What happens in disc degeneration?
Dehydration of discs with age
Causes them to bulge
What happens in disc prolapse?
Protrusion of nucleus polposus
Slight impingement into vertebral canal
What happens in disc extrusion?
Nucleus polposus breaks through annulus fibrosus
But still within disc space
What happens in sequestration?
Nucleus polposus breaks through annulus fibrosus
Separates from main body of disc
Enters vertebral canal
Which disc does slippage most commonly occur in?
L4/L5 disc
L5/S1 disc
What are the different types of disc herniation? What is the relative prevalence of each?
Paracentral - most common
Far lateral - rare
Canal filling - rare
What is a paracentral disc herniation?
Disc herniates into spinal canal
next to the spinal cord
What is a far lateral disc herniation?
Disc herniates laterally where nerve root is exiting
not in spinal canal
What is a canal filling disc herniation?
Large disc herniation
Fills spinal canal
What does a canal filling disc herniation result in?
Cauda equina syndrome
What is sciatica?
Compression of nerve roots which contribute to the sciatic nerve L4-S3
NOT compression of the sciatic nerve!
What is the most common cause of sciatica?
Disc prolapse
Which nerve roots are most commonly compressed in sciatica?
L4, L5, S1
Why is sciatica of S2, S3 rare?
Because they exit from the sacrum
which doesn’t have any discs in it
What are the symptoms of sciatica?
Pain - along whole course of nerve
Paraesthesia - only end point that nerve supplies
Where does pain occur with L4 sciatica?
Anterior thigh
Anterior knee
Medial shin
Where does paraesthesia occur with L4 sciatica?
Medial shin
Where does pain occur with L5 sciatica?
Lateral thigh
Lateral calf
Dorsum of foot
Where does paraesthesia occur with L5 sciatica?
Lateral calf
Dorsum of foot
Where does pain occur with S1 sciatica?
Posterior thigh
Posterior calf
Heel
Sole of foot
Where does paraesthesia occur with S1 sciatica?
Heel
Sole of foot
Which nerve root is compressed by a paracentral disc prolapse?
The lower nerve root
Because upper nerve root has already left
Lower nerve root is starting to leave spinal cord
gets compressed
What nerve root would be compressed by an L5/S1 disc prolapse?
S1
Which nerve root is affected by a far lateral disc prolapse?
The upper nerve root
Because the upper nerve root is leaving laterally
gets compressed
What age group do slipped discs mostly occur in?
30-50 year olds
Are slipped discs usually resolved?
Yes
What is cauda equina syndrome caused by?
Canal filling disc prolapse
What is compressed in cauda equina syndrome?
Cauda equina - lumbar and sacral nerve roots
What age group does cauda equina mostly occur in?
30-50 year olds
same as slipped discs, since it’s the cause
What are the symptoms and signs of cauda equina syndrome?
Bilateral sciatica - both nerve roots compressed
Perianal numbness - loss of S3, S4 supply
Painless retention of urine
Urinary and faecal incontinence - loss of sphincter control
What does CSF normally look like on an MRI?
Appears white
What does cauda equina syndrome look like on an MRI?
Disc prolapse appears dark - grey/black
where CSF should be
How quikcly should cauda equina syndrome be treated?
Within 48 hours of sphincter symptoms
What are the consequences of cauda equina syndrome that’s untreated or treated too late?
Intermittent self catheterisation
Digital rectal examinations
Sexual dysfunction
What is lumbar canal stenosis?
Narrowing of spinal canal in lumbar region
What are the causes of lumbar canal stenosis?
Disc bulge
Facet joint osteoarthritis
Ligamentum flavum hypertrophy
What age group does lumbar canal stenosis mostly occur in?
Elderly
What does lumbar canal stenosis look like on an MRI scan?
Little CSF, white
Appears darker - grey black
What is claudication?
Pain in legs when walking
What are the causes of claudication?
Neurogenic - lumbar canal stenosis
Vascular - problems with perfusion of legs
Does lumbar canal stenosis improve?
No
most people stay the same
Which group of people should be treated for lumbar canal stenosis?
Restricted walking distance affects their quality of life
What is spondylolisthesis?
Slip forwards of vertebra above
on vertebra below
What are the types of spondylolisthesis?
Dysplasic Isthmic Degenerative Iatrogenic Pathological
What is dysplastic spondylolisthesis?
Abnormality in shape of facet joints is the cause
What is isthmic spondylolisthesis?
Defect in pars interarticularis is the cause
What is pars interarticularis?
Bone that joins facet joints to vertebral body
What is degenerative spondylolisthesis?
Arthritis is the cause
What is iatrogenic spondylolisthesis?
Caused by medical process e.g. surgery
What is pathological spondylolisthesis?
Caused by disease e.g. tumour
What are the causes of a defective pars interarticularis?
Abnormality in development
Fractures
What happens with a fractured pars interarticularis?
Vertebral body detached from vertebral arch
Vertebral body moves forwards
no compression of spinal cord
How does isthmic spondylolisthesis present?
Back pain
L5 sciatica
arch not intact so no spinal canal stenosis
What does disc prolapse look like on an MRI?
Dark grey area in white CSF
What happens to the prolapsed disc material?
Triggers inflammatory reactions
broken down by it
Where does isthmic spondylolisthesis commonly occur?
L5 vertebrae
In what age groups does isthmic spondylolisthesis present? Why?
Adolescence
Adulthood
Disc has started to age
How does degenerative spondylolisthesis present?
Presents with claudication
Why does degenerative spondylolisthesis present with claudication?
Posterior arch intact
as vertebrae moves forward it compresses the spinal cord within the canal
Facet joint osteoarthritis gives stenosis of canal
How is spondylolisthesis treated?
Put vertebrae back into place
Screws and rods hold it in place
