Cauda Equina Syndrome


Cauda Equina Syndrome, Epidural Compression Syndrome

  • See Also
  • Pathophysiology
  1. Massive Central DIsc protrusion
  2. Compression of lumbar spinal nerve roots
  • Precautions
  1. Maintain a high index of suspicion
  2. Delayed diagnosis or misdiagnosis is not uncommon (even by neurosurgical senior residents)
    1. Bell (2007) Br J Neurosurg 21(2): 201-3 [PubMed]
  • Causes
  • Symptoms
  1. Bilateral Sciatica
    1. See also Lumbar Stenosis for extensive description
    2. Dull aching pain in perineum, Bladder or Sacrum
    3. Radiation to Buttock and leg
    4. Provoked by Exercise or prolonged standing
    5. Relieved with rest or forward bending
  2. Neurologic Changes
    1. Saddle Anesthesia
      1. Change in Sensation when wiping with toilet paper
    2. Bowel Incontinence or Constipation
    3. Urinary BladderIncontinence or acute Urinary Retention
    4. Acute Erectile Dysfunction
  • Signs
  1. Loss of perineal Sensation or perineal reflex (or Anal Wink)
    1. May best correlate with cauda equina findings on MRI
  2. Loss of Rectal Tone
    1. Resting tone applies pressure to inserted finger without patient bearing down
    2. Patient tries to resist Defecation
      1. Puborectalis Muscle contracts and applies pressure to the anterior inserted finger
      2. External anal sphincter contracts and applies pressure circumferentially around the inserted finger
    3. Patient bears down
      1. Pressure on inserted finger increases
    4. Overall poor efficacy of Rectal Tone to diagnose S2-S4 neurologic deficit
      1. Tabrah (2022) Musculoskelet Sci Pract 58:102523 +PMID: 35180641 [PubMed]
  3. Loss of Bulbocavernosus Reflex
  4. Increased post-void residual Urine Volume
  5. Foot Drop
    1. Ankle dorsiflexion bilateral weakness
    2. Absent Ankle Jerk
  • Imaging (See Lumbar Stenosis)
  1. L-Spine MRI (preferred)
  2. CT Myelography
    1. Indicated if MRI contraindicated
  • Lab (Indicated if Epidural Abscess or other infection suspected)
  • Diagnosis
  • High yield exam findings
  1. Altered perineal Sensation
  2. Increased post-void residual
  3. Abnormal Rectal Tone
    1. More recent evidence (see above) suggests Rectal Tone is an unreliable test for cauda equina
  • Differential Diagnosis
  • Back Pain with Acute Neurologic Symptoms (e.g. Cord Syndrome, Peripheral Neuropathy)
  1. Central Spinal Stenosis (including cauda equina)
  2. Spinal Infection (e.g. Spinal Epidural Abscess, Discitis)
  3. Aortic emergencies (Aortic Dissection, Abdominal Aortic Aneurysm, Claudication)
  4. Neurologic Syndromes (Multiple Sclerosis, Guillain-Barre, Transverse Myelitis)
  • Management
  1. Neurologic Deficits suggest Cauda Equina Syndrome
  2. Immediate Neurosurgery Consultation
  • Prognosis
  1. Delay >72 hours risks permanent neurologic deficit
  • References
  1. Cali and Bond (2022) Crit Dec Emerg Med 36(7): 4-11
  2. Swaminathan, Shoenberger and Long in Swadron (2023) EM:Rap 23(3): 19-21
  3. Balasubramanian (2010) Br J Neurosurg 24(4): 383-6 [PubMed]