Lumbar spine pathologies

Question 1

Name 5 lumbar pathologies

Answer 1

Mechanical back pain
Prolapsed intervertebral discs
Spinal stenosis
Spondylolisthesis
Spinal infection and tumours

Question 2

What is mechanical back pain? What are some risk factors?

Answer 2

It is characterised by pain when the spine is loaded, that worsens with exercise and is relieved by rest
Risk factors: obesity, poor posture, a sedentary lifestyle with deconditioning of the paraspinal (core) muscles, poorly-designed seating and incorrect manual handling (bending and lifting) techniques

Question 3

What are the 4 stages of disc herniation?

Answer 3

1. Disc degeneration: chemical changes associated with ageing cause discs to dehydrate and bulge
2. Prolapse: protrusion of the nucleus pulposus occurs with slight impingement into the spinal canal. The nucleus pulposus is contained within a rim of annulus fibrosus
3. Extrusion: the nucleus pulposus breaks through the annulus fibrosus but is still contained within the disc space
4. Sequestration: the nucleus pulposus separates from the main body of the disc and enters the spinal canal

Question 4

What are the three types of prolapse?

Answer 4

Paracentral prolapse (transversing root more at risk) 
Central herniation (risk of causing cauda equina syndrome) 
Far lateral herniation

Question 5

What is sciatica? What are the 5 nerve roots of the sciatic nerve?

Answer 5

Sciatica is pain caused by irritation or compression of one or more of the nerve roots which contribute to the sciatic nerve (L4, L5, S1, S2 + S3)
L4 = anterior thigh, anterior knee, medial leg
L5 = lateral thigh, lateral leg, dorsum of foot
S1 = posterior thigh, posterior leg, heel, lateral border and sole of foot

Question 6

What is cauda equina syndrome? What are the five red flag symptoms?

Answer 6

Cauda equina syndrome can develop in the context of prolapsed intervertebral disc when there is a ‘canal filling disc’ that compresses the lumbar and sacral nerve roots within the spinal canal
Bilateral sciatica
Perianal numbness (saddle anaesthesia)
Painless retention of urine
Urinary / faecal incontinence
Erectile dysfunction

Question 7

What is the treatment for cauda equina syndrome? What happens if left untreated?

Answer 7

Cauda equina syndrome needs to be treated by surgical decompression within 48 hours of the onset of sphincter symptoms
The consequences of missing this diagnosis are serious and life-changing e.g. chronic neuropathic pain, impotence, having to perform intermittent self catheterisation to pass urine, faecal incontinence

Question 8

What is neurogenic claudication?

Answer 8

Neurogenic claudication (or pseudoclaudication) is when the patient reports pain and/or pins and needles in the legs on prolonged standing and on walking, radiating in a sciatica distribution

Question 9

What is spondylolisthesis and what are the different categories?

Answer 9

Spondylolisthesis is anterior displacement of the vertebra above relative to the vertebra below. It is classified into various types according the underlying cause:

• Congenital or dysplastic: congenital instability of the facet joints
• Isthmic: a defect in the pars interarticularis
• Degenerative: results from facet joint arthritis and joint remodelling (age >50 years)
• Traumatic: acute fractures in the neural arch, other than the pars interarticularis
• Pathological: infection or malignancy
• Iatrogenic: caused by surgical intervention e.g. if too much lamina and facet joint is excised during a laminectomy operation

Question 10

What is a lumbar puncture? State the layers a lumbar puncture must go through

Answer 10

Lumbar puncture is the withdrawal of fluid from the subarachnoid space of the lumbar cistern (CSF)
Skin, subcutaneous fat, ligamentum flavum, epidural fat and veins, dura mater, arachnoid mater