Cauda Equina syndrome

Question 1

What is cauda equina?

Answer 1

• Defined by a consellation of symptoms that result from terminal spinal nerve root compression in the lumbosacral region
• one true few medical emergencies

Question 2

What are the key features of cauda equina?

Answer 2

• Bilateral leg pain
• Bladder and bowel dysfunction
• Saddle anaesthesia
• lower extremity sensorimotor changes

Question 3

What is the epidemiology of cauda equina?

Answer 3

• 1-6% lumbar disc herniations

Question 4

What is the pathophysiology of cauda equina?

Answer 4

• Space occupying lesions within lumbosacral canal including
  
  • disc herniation- most common
  • spinal stenosis
  • tumours
  • trauma- retropulsion of fracture fragment
  • spinal epidural haematoma
  • epidural abscess

Question 5

Name any associated conditions of cauda equina?

Answer 5

• DVT
  
  • complx from spinal trauma/surgery

Question 6

Can you describe the anatomy of the terminal spinal cord and nerve supply to the bladder?

Answer 6

• Conus Medullaris
  
  • tapered, terminal end of spinal cord
  • T12/ L1 vertebral body
• Filum Terminale
  
  • non neural, fibrous extension of conus medullaris that attaches to cocyx
  • compression-> LMN

Bladder

• innervation from
• parasympathetic- pelvic splanchnic/inf hypogastric
• sympathetic- hypogastric n’s
• external sphincter controlled by Pudendal nerve
• LMN lesions of cauda equina will interupt nerve forming bladder arcs

Question 7

What is the symptoms and signs of cauda equina?

Answer 7

Hx

• acute ( dissc herniation) vs insidious ( tumour/spinal stenosis)

Symptoms

• bilateral leg pain
• sadddle anaethesia
• Impotence
• sensorimotor loss in lower extremity
• neurogenic bladder dysfunction
  
  • disruption of bladder contraction & sensation-> urinary retention & then overflow

Signs

• Inspection
  
  • lower leg muscle atrophy with insidious presentation- spinal stenosis
  • fascilations rare
• Palpation
  
  • bladder - urinary retention
  • lower back- tenderness?
• NV examination
  
  • bilat lower extremity weakness/sensory disturbance
  • decrease or absent reflexes
• Rectal exam
  
  • reduced /absent sensation to pinprick in perianal region (s2-4 dermatones)
  • Decreased rectal tone/voluntary contracture
  • diminished or asbent anal wink test /bulbocavernosus relfex

Question 8

What investigations are useful in dx of cauda equina?

Answer 8

• MRI
  
  • to evaluate neurological compression
• Ct Myelogram for those with pacemakers

Question 9

What is the tx of cauda equina?

Answer 9

Surgery

• Urgent Surgical Decompression within 48hrs
  
  • sig suspicion of CES
  • severity of symptoms increase urgency of surgical decompression
• Discectomy or Laminectomy
• outcomes
  
  • improved outcomes in bladder/bowel fucntion and resolution of motor and sensory deficits when decompression preformed within 48 hrs of onset of symptoms

Question 10

Describe the surgical approach to urgent decompression?

Answer 10

• Posterior midline approach to spine
• discectomy vs wide laminectomy and discectomy

Question 11

What are the complications of delayed presenatation of CES or surgery on CES?

Answer 11

• Sexual dysfunction
• Urinary dysfunction requiring catherisation
• chronic pain
• Persistent leg weakness