Cauda Equina Compression¶

Pathophysiology¶

• Compression of lumbosacral nerve roots within the spinal canal
• Common causes:
  • Herniated lumbar disc (most frequent)
  • Spinal stenosis
  • Tumour (primary or metastatic)
  • Trauma
  • Epidural abscess or haematoma
• Leads to ischaemia and potential permanent nerve damage if not treated promptly

Demographics¶

• Incidence: 1-3 cases per 100,000 population per year
• Most common in adults aged 30-50 years
• Slightly more prevalent in males
• Risk factors:
  • Degenerative disc disease
  • History of spinal surgery
  • Spinal trauma
  • Coagulopathies (for epidural haematoma)

Diagnosis¶

• Clinical presentation:
  • Low back pain
  • Bilateral sciatica
  • Saddle anesthesia
  • Bladder and/or bowel dysfunction
  • Lower extremity weakness
• Physical examination:
  • Reduced perianal sensation
  • Decreased anal sphincter tone
  • Lower extremity motor and sensory deficits
• Diagnostic criteria:
  • One or more of: bladder/bowel dysfunction, reduced sensation in saddle area, sexual dysfunction
  • Plus one or more of: low back pain, bilateral sciatica, lower extremity sensorimotor deficits

Imaging¶

• MRI:
  • Gold standard for diagnosis
  • T1-weighted: assess vertebral body alignment and marrow changes
  • T2-weighted: evaluate disc herniations, spinal cord, and nerve root compression
  • Gadolinium-enhanced: useful for detecting tumours or infections
• CT myelography:
  • Alternative when MRI is contraindicated
  • Shows compression of nerve roots and thecal sac
• Plain radiographs:
  • Limited utility, may show vertebral body misalignment or fractures
• CT:
  • Useful for assessing bony abnormalities and fractures

Treatment¶

• Urgent surgical decompression, ideally early, for progressive deficit
• Directed at the cause (discectomy, tumour resection, abscess/haematoma evacuation)

Differential diagnosis (compressive/enhancing cauda equina)¶