What type of disc protrusion causes cauda equina syndrome?
Central disc protrusion
What type of joints are intervertebral discs?
Secondary cartilagenous
What are the components of the intervertebral discs?
Annulus fibrosus iis the though outer layer
Nucleus pulposus is the gelatinous core
•Annulus may tear and nucleus prolapse
–Can cause cord / nerve root compression
What connects the discs with the vertebral bodies?
The ALL and the PLL
- The fibres of the annulus fibrosis (collagen) run obliquely and alternately between layers
- They resist rotational movements
- Discs fail with twisting movements
What is the nucleus pulposus made up of?
Mainly of water
and collagen and proteoglycans (very hydrophilic)
The disc is kidney bean shaped - what dircetion are disc prolapses usually?
Usually posterolateral
What is the normal ageing process of the intervertebral discs?
Water content decreases, disc space is narrowed. This process is usually increased by smoking
What are the possible courses of pathology after the annulus fibrosis has been torn and the nucleus pulposus starts to protrude outwards?
Nerve root compression by osteophytes
Central spinal stenosis
Abnormal movement: spondylolysis - (this is a stress fracture of the pars interarticularis of the vertebral arch)
Spondylolisthesis - The displacement of one vertebra in relation to another
What are the key features of radiculopathy?
Limb pain is worse than back pain
Pain in a nerve root distribution
What is the therapy for nerve root pain?
- Most will settle, about 90% in 3 months
- Physiotherapy
- Strong analgesia
- Referral after 12 weeks
- Imaging
–MRI
What are the different classification of slipped disc?
Bulge
Protrusion - annulus is weakened but still intact
Extrusion Through annulus but in continuity
Sequestration - dessicated disc material free in canal
What is the most ocmmonly affected disc prolapse in the cervical spine?
Most commonly the C5/C6 disc
What percentage of slipped discs are thoracic slippled discs?
Less than 1%
They are mid to lower levels (most are at the T11 - T 12 part)
Herniations are central, posterolateral and lateral
Where are the common places for lumbar herniations?
•Usually L4/5 (45%), followed by L5/S1 (40%), then L3/4 (10%)
Most prolapses are posterolateral (posterior longitudinal ligament is the weakest)
Central dis may give pain in both legs, or may be back pain only
Which nerve root and disc are associated with the following clinical picture?
Sensory loss: Little toe and sole of foot
Motor weakness: Plantar flexion of foot
Reflex change: Ankle jerk
Disc - L5/S1
Nerve root - S1
Which nerve root and disc are associated with the following clinical picture?
Sensory loss - great toe and first dorsal web space
Motor weakness - EHL
Reflex change - none
Disc - L4/L5
Nerve root - L5
Which nerve root and disc are associated with the following clinical picture?
Sensory loss - medial aspect of lower leg
Motor weakness - quads
Reflex change - knee jerk
Disc - L3/L4
Nerve root - L4
What is the management of suspected cauda equina?
Urgent MRI
Emergency surgery within 48 hours - delay results in permanent dysfunction
•sacral nerve roots compressed – can result in permanent bladder and anal sphincter dysfunction and incontinence
What are the common causes of cauda equina syndrome?
–central lumbar disc prolapse (commonest)
–tumours
–trauma (burst or Chance #, disc) or spinal stenosis
–infection (epidural abscess)
–iatrogenic (spinal surgery or manipulation, spinal epidural injection)
Chance fracture results from excessive flexion of the spine and is frequently unstable
What are the clinical features of cauda equina syndrome?
–Injury or precipitating event
–Location of symptoms (bilat buttock & leg pain + varying dysaethesiae + weakness – beware)
–Bowel or bladder dysfunction (urinary retention +/- incontinence overflow)
–PR exam - saddle anaesthesia (perianal loss of sensation), loss of anal tone & anal reflex
–High index of suspicion in spinal post-op patients with increasing leg pain in presence of urinary retention
What is the investigation for cauda equina if MRI is contraindicated?
Lumbar CT myelogram
What are the potential outcomes for cauda equina syndrome?
After discoectomy still cases of:
Abnormal urinary function
Motor deficits
Sensory deficits
Perianal parasthesiae
Persistent sexual dysfunction
Where does the degeneration of cervical and lumbar spondylosis occur?
Facet joints
Discs
Ligaments
Spondylosis is referred to as arthritis of the spine
What are the outcomes of spondylosis?
Compression of nerve roots as well as the entire spinal cord (myelopathy)
Signs of myelopethy are UMN (increased tone, brisk reflexes)
Where do you find the posterior longitudinal ligament?
Inside the vertebral canal along the backs of the vertebral bodies
What ligament links the lamina?
Ligamentum flavum
What is the name of the ligmant that links the transverse processes?
Intertransverse ligament
When is neurogenic claudication common?
Lumbar spinal stenosis
Causes impingement or inflammation of the nerves leaving the spinal cord
What are features of spinal claudication?
–Usually bilateral
–Sensory dysaesthesiae
–Poss weakness (drop foot – tripping)
–Takes several minutes to ease after stopping walking
–Worse walking down hills because the spinal canal becomes smaller in extension, better walking uphill or riding bicycle
Neurogenic claudication may present in one or both legs and usually presents as some combination of discomfort, pain, numbness and weakness in the calves, buttocks, and/or thighs. In some patients, it is precipitated by walking and prolonged standing. The pain is classically relieved by a change in position or flexion of the waist
What are the types of spinal stenosis?
Lateral recess stenosis - where the disc prolapse most commonly affects the nerve
Central stenosis
Foraminal stenosis
What is the treatment of lateral recess stenosis?
–Non-operative
–Nerve root injection
–Epidural injection
–Surgery
What are the causes of lateral recess stenosis?
A bulging or herniated disc
Degenerative disc disease
An enlarged facet joint
Facet syndrome
A thickened spinal ligament
A misaligned vertebra (spondylolisthesis)
A bone spur
Spinal inflammation (osteoarthritis)
What are the clinical features of central stenosis?
Lower back pain, tingling or numbness may radiate to the hips, buttocks, legs and sometimes the toes
Dull and aching pain concentrated in the lower back may come and go; this pain may become more persistent over time or with movement such as running, walking, standing or bending
In severe cases, leg pain and weakness can cause difficulty balancing and walking
What is the treatment for central stenosis?
–Non-operative
–Epidural steroid injection
–Surgery (80% improve)
What is treatment for foraminal stenosis?
–Non-operative
–Nerve root injection
–Epidural injection
–Surgery
What is the treatment of spondylolisthesis?
•Symptoms
–Often vary with type of spondylolisthesis
–Treatment depends on symptoms
- Conservative with lifestyle changes
- Surgery for persistent pain +/- nerve root entrapment
