Cauda Equina Syndrome

• The Cauda Equina is a collection of nerve roots that travel through the spinal canal after the spinal cord terminates at L1

  The spinal cord ends and tapers down in a section called the conus medullaris
• Causes of cauda equina syndrome:

  • Lumbar disc herniation - can be secondary to degenerative disc disease, trauma or infection
  • Spinal fractures of subluxation
  • Malignancy
  • Spinal infection
  • Iatrogenic - spinal anaesthesia
• Typical symptoms of cauda equina syndrome:

  • Severe back pain
  • Bilateral sciatica
  • Perianal (saddle) anaesthesia
  • bladder dysfunction - most commonly urinary retention
  • Bowel incontinence
  • Sexual dysfunction
• Typical clinical findings on lower limb examination include lower motor neuron signs such as:

  • Hypotonia
  • Bilateral or unilateral weakness
  • Areflexia
  • Abnormal sensory changes
• Typical findings of cauda equina syndrome on a rectal exam:

  • Saddle anaesthesia - loss of perianal sharp/crude touch discrimination
  • Reduced perineal sensation
  • Reduced anal sphincter tone/loss of anal squeeze
• A brief abdominal examination should be performed to assess for a palpable bladder - indicative of urinary retention
• Patients with suspected cauda equina syndrome require an urgent MRI
• If a reversible cause of CES can be seen on the MRI - then urgent surgical decompression should be performed
• Complications of cauda equina syndrome:

  • Paraplegia
  • Lower limb numbness
  • Chronic urinary retention or incontinence
  • Chronic sexual dysfunction
• Cauda equina syndrome is a type of radiculopathy
• Patients with incomplete CES will complain about urinary difficulties, altered urinary sensation, loss of desire to void, hesitancy and urgency.
• Patients with complete CES demonstrate definitive urinary retention with associated overflow incontinence. Both classifications require urgent further investigation.