Cauda Equina Syndrome (CES) involves impairment of bladder, bowel or sexual function and perianal or saddle numbness due to dysfunction of the sacral and lumbar nerve roots within the vertebral canal. The most common causes are disc herniation, tumors, infection, and spinal stenosis. Early diagnosis through examination of symptoms and MRI imaging is important, as early surgical decompression within 24 hours of onset improves patient outcomes and reduces long-term disability. Treatment involves relieving pressure on the nerves through wide laminectomy and decompression surgery. Rehabilitation focuses on mobilization while limiting exertion to allow scar tissue to form.

1. Cauda Equina Syndrome
Dr. Bhanubhakta Chalise
Moderator: Assoc. Prof. Dr. Pramod Devkota
Jun 30, 2021

2. Spinal cord Anatomy
–Conus medullaris
▪ tapered, terminal end of the spinal cord
▪ terminates atT12 or L1 vertebral body
–Filum terminale
▪ non-neural, fibrous extension of the conus
medullaris that attaches to the coccyx
–Cauda equina (horse's tail)
▪ collection of L1-S5 peripheral nerves
within the lumbar canal

3. Spinal cord cross-section

4. DERMATOMES

5. Dermatomes
important
for CES

7. Bladder control

8. Bowel
control

9. Definition
▪ CES is a syndrome of symptoms and signs with a prevalence is one case per 33,000 to
one case per 100,000
▪ Although there is no agreed definition of CES, the five characteristic features, not all of
which need to be present to make the diagnosis are
– Bilateral neurogenic sciatica,
– Reduced perineal sensation,
– Altered bladder function ultimately to painless urinary retention,
– Loss of anal tone and
– sexual dysfunction.
▪ There is no symptom or sign or combination that reliably diagnoses (or excludes) CES

10. Etiologies

11. The most common causes of CES in
decreasing order
▪ Disc Herniation(45%)
– One to 3% of lumbar disc herniations result in cauda equine syndromeTumour
▪ Infection
▪ Stenosis
▪ Haematoma
▪ Inflammatory
▪ Vascular

12. HISTORY
Five characteristic features of CES are consistently described in the
literature and should form the basis of questions related to diagnosis:
▪ Bilateral neurogenic sciatica -
– Pain associated with the back and/ or unilateral/bilateral leg symptoms may be
present.
▪ Reduced perineal sensation -
– Sensation loss in the perineum and saddle region is the most commonly
reported symptom.
▪ Altered bladder function leading to painless retention -
– Bladder dysfunction is the most commonly reported symptom and can range
from increased frequency , difficulty in micturition, change in stream,
incontinence and retention

13. ▪ Loss of anal tone -
– loss or reduced anal tone may be evident if a patient reports bowel dysfuntion.
Bowel dysfunction may include incontinence, inability to control motions,
inability to feel when the bowel is full and consequently overflow.
▪ Loss of sexual function -
– Sexual dysfunction is not widely mentioned in the literature but is an important
aspect that should be discussed with patients

15. Physical exam
▪ Inspection
–lower extremity muscle atrophy with insidious
presentations (e.g. spinal stenosis)
–fasciculations are rare
▪ Palpation
–lower back pain/tenderness is not a distinguishing
feature
–palpation of the bladder for urinary retention

16. ▪ Neurovascular examination
– bilateral lower extremity weakness and sensory disturbances
– decreased or absent lower extremity reflexes
▪ Rectal/genital examination
– reduced or absent sensation to pinprick in the perianal region
(S2-S4 dermatomes), perineum, and posterior thigh
– decreased rectal tone or voluntary contracture
– diminished or absent anal wink test and a bulbocavernosus
reflex

17. Three common PATTERNS of presentations (Tandon
and Sankaran)
1. Rapid onset in the absence of prior back problems,
2. Acute bladder dysfunction with a history of low back pain with
or without sciatica, and
3. Chronic back pain and sciatica with gradually worsening pain
combined with bladder and bowel dysfunction
Approximately 70% of patients have a history of chronic back pain
However, CES may present acutely or gradually over weeks to months

22. Classification of symptoms and likely outcome

23. Imaging
▪ MRI
– Study of choice to evaluate neurological compression due to its ability to
accurately depict soft tissue pathology.
▪ CT myelography
– Study of choice if patient unable to undergo MRI
▪ Plain films
– Generally unhelpful for disc herniation
–Can provide valuable information in the setting of acute
trauma.

24. ▪ Inflammatory markers and CSF studies
– Inflammatory or infectious aetiology is being considered.
▪ A point-of-care ultrasound
– Performed to assess for the bladder volume immediately after a patient voids.
– One study found that a post-void volume N500 mL had an odds ratio of 4.0 for
diagnosing CES .
– However, the odds ratio increased to 48.0 when this was combined with two of
the following three symptoms: bilateral sciatica, subjective complaints of
urinary retention, or rectal incontinence symptoms

25. Levels of
herniations

27. TREATMENT
▪ What constitutes cauda equina syndrome (CES), how it should be
subclassified and how urgently to image and operate on patients
with CES are all matters of debate

28. ▪ The role of surgery is to relieve pressure from the nerves in the cauda
equina and to remove the offending elements.
▪ Treatment depends on the underlying cause with wide laminectomy
and extensive decompression being the accepted surgical technique
for a large lumbar disc herniation.

29. Surgical Techniques: Surgical
decompression of neural elements
–approach
▪ posterior midline approach to lumbar spine
–dissectomy vs. wide laminectomy and
dissectomy
▪ no comparison studies between microdiskectomy
alone and wide decompression combined with
microdiskectomy.

30. Surgical timing and outcome
▪ CESS
▪ Elective surgery is preferred rather than emergency surgery.
▪ The diagnosis could be wrong . EMG could be helpful in such cases.
▪ CESI
▪ If the MRI findings are positive & clinical symptoms indicate CESI, surgery as soon as possible.
▪ Most with CESI have normal bladder and bowel after surgery. Sexual function may decrease.
▪ CESR
▪ There should be no delay for surgical decompression.
▪ Direct surgery is the only option in this situation.
▪ The patients are often paralysed, have insensate bladder/bowel, and usually no sexual function
are remained.

31. BRITISH JOURNAL OF NEUROSURGERY, 2016VOL. 30, NO. 5, 518–522
http://dx.doi.org/10.1080/02688697.2016.1187254
Standards of care in cauda equina syndrome
N.V.Todda and R. A. Dicksonb University of Leeds, Leeds, UK

32. REHABILITATION
▪ After recovery from an acute disc rupture, or disc removal, the
patient is mobilized and needs to limit physical exertion until 6−8
weeks to allow the annular defect to scar up and minimize re-
prolapse.
▪ Nonimpact exercises are usually safe.

33. NON-INTERVENTIONAL TREATMENTS
▪ Bedrest, heat, ice, short course of analgesics,
▪ Non-steroidal anti-inflammatory drugs (NSAIDs),
▪ Antidepressants and muscle relaxants
▪ Massage, spinal manipulation, spinal traction, acupuncture, exercise
therapy

34. STEROIDS ?
▪ Steroids have not been shown to benefit patients with head or spinal
cord injury.
▪ They are of value in inflammatory polyneuropathies.
▪ The utility of steroids in CES is unknown.

35. Complications
Major determinant : Delayed presentation or decompression
– sexual dysfunction
– urinary dysfunction requiring catheterization
– chronic pain
– persistent leg weakness

36. Summary
▪ CES results from dysfunction of the sacral and lumbar nerve roots
within the vertebral canal producing impairment of bladder, bowel or
sexual function and perianal or saddle numbness. Evaluation of these
findings in the clinical examination is crucial.
▪ The number of potential aetiologies is vast but the most common
causes are disc herniation, tumours, infection, spinal stenosis,
inflammatory causes and vascular occlusion.
▪ Early surgical decompression is advocated by most authors to best
aid patient recovery and reduce long term disability.
▪ There is evidence to suggest intervention within 24 hours
significantly improves outcomes.

37. References:
▪ Apley & Solomon's System of Orthopaedics andTrauma 10th Edition
▪ Miller’s Review of Orthopaedics 7th Edition
▪ BRITISH JOURNALOF NEUROSURGERY, 2016VOL. 30, NO. 5, 518–522, Standards of care in
cauda equina syndrome
▪ Long B, KoyfmanA, Gottlieb M. Evaluation and management of cauda equina syndrome in the
emergency department.Am J Emerg Med. 2020 Jan;38(1):143-148. doi:
10.1016/j.ajem.2019.158402. Epub 2019Aug 20. PMID: 31471075.
▪ Todd NV. Guidelines for cauda equina syndrome. Red flags and white flags. Systematic review and
implications for triage. Br J Neurosurg. 2017 Jun;31(3):336-339. doi:
10.1080/02688697.2017.1297364. Epub 2017 Mar 2. PMID: 28637110.
▪ Dionne N, Adefolarin A, Kunzelman D,Trehan N, Finucane L, Levesque L,Walton DM, Sadi J.
What is the diagnostic accuracy of red flags related to cauda equina syndrome (CES), when
compared to Magnetic Resonance Imaging (MRI)?A systematic review. Musculoskelet Sci Pract.
2019 Jul;42:125-133. doi: 10.1016/j.msksp.2019.05.004. Epub 2019 May 17. Erratum in:
Musculoskelet Sci Pract. 2019Oct;43:128. Erratum in: Musculoskelet Sci Pract. 2021
Jun;53:102355. PMID: 31132655.