• Compression of the cauda equina, containing 18 nerve roots (L2 – S5)
  • Clinical picture
    • Lower back pain radiating to legs
    • Wasting, usually no fasciculations
    • Arreflexia in the legs (ankles affected first)
    • Weakness
      • Ankle plantarflexion (S1/S2)
      • Knee flexion (L5/S1)
      • Hip extension (L5/S1)
      • May involve more muscle groups as compression worsens
    • Sensory loss in all modalities in dermatomes supplied by affected roots
    • May have urinary retention, lax anal tone (must do digital rectal examination)
  • Causes
    • Intervertebral disc herniation
    • Epidural abscess
    • Epidural tumor
    • Intradural extramedullary tumour
    • Carcinomatous meningitis
    • Bony metastases
  • Investigation
    • Magnetic resonance imaging of the lumbosacral spine
  • Management
    • Emergency radiotherapy
    • Steroids (dexamethasone 16mg daily in divided doses)
    • Neurosurgical referral for surgical decompression and stabilization