cauda equina

Question 1

what is the most common motor deficit?

Answer 1

foot drop - tib ant solely innervated by L4

Question 2

types and management of cauda equina syndrome?

Answer 2

• CESS - suspected - bilateral radiculopathy - admit - operate or watch & wait
• CESI - incomplete - urinary difficulties - emergency surgery
• CESR - retention - painless retention of urine and painless overflow incontinence - early (<12hrs) emergency surgery, late (>12hrs) next available list
• CESC - complete - paralysed insensate bladder/ bower, patulous anus and absent perianal sensation - next available list

Bladder/ bowel function better preserved if operate within 24hrs

BASS guidance - surgery at earliest convenient opportunity, taking into consideration potential for increased morbidity
- no safe time limit to wait

Question 3

common symptoms of cauda equina

Answer 3

• bilateral radiculopathy
• bladder/ bowel/ sexual dysfunction
• saddle anaesthesia
• sensorimotor dysfunction

post void bladder scan > 200ml

Question 4

causes of cauda equina

Answer 4

• lumbar disc prolapse
• haematoma
• infection
• tumour
• lumbar spinal stenosis
• haematoma

Question 5

surgical management of cauda equina

Answer 5

Perioperative prep
* prone, spinal table and IV antibiotics
* spinal monitoring
* consented, marked and who checklist

Skin incision and superficial dissection
* II - level check prior to incision
* longitudinal midline incision
* subperiosteal elevation of the paraspinal muscles (erector spinae) off the spinous process and lamina using a cobb
* avoid stripping facet joint capsule - risk of later degeneration
* mcculloch retractor

deep dissection
* level recheck - nibble small area of spinous process to denote the level
* inferior half of spinous process removed with osteotome
* laminotomy performed - burr 5mm
* ligamentum flava debrided
* medial undercutting facetectomies to remove the medial border of the facet joints
* retract dura and nerve roots
* disc occluding the canal removed with pituitary rongeurs - entirety of disc not needed to be removed

laminotomy - part of lamina removed
laminectomy - most of lamina removed

Question 6

Complications of operative care

Answer 6

Complications of operative care
* Dural tears
* Iatrogenic segmental instability – overly aggressive medial fasciectomy
* Epidural fibrosis
* Wound infection – 1%
* Vascular injury