What is Cauda Equina Syndrome (CES)?

Cauda Equina Syndrome is a spinal surgical emergency that can lead to lower limb paralysis and loss of bowel, bladder and sexual function if not assessed and treated urgently. Without early interventions, the possible consequences can be devastating.

The cauda equina is a bundle of spinal nerve roots that extend from the lower end of the spinal cord in the lumbar region of the spine.

It is situated within the vertebral canal and consists of spinal nerve roots that emerge from the spinal cord and travel down through the spinal canal before branching out to various parts of the lower body, including the lower back, pelvis, buttocks and lower extremities.

Whilst the cauda equina is protected by the vertebrae, it is still vulnerable to damage or compression, which can lead to a condition called Cauda Equina Syndrome.

CES Made Simple

Causes of Cauda Equina Syndrome

Cauda Equina Syndrome is a set of specific symptoms that occur when the nerve roots that emerge from the end of the spinal cord at L2/L3 are compressed to such a degree that function and sensation to the parts of the body they serve become compromised.

There are different ways the cauda equina can become compressed. The most frequent cause is a herniated, slipped or prolapsed disc, but it can also occur due to other reasons such as:

  • Spinal lesions or tumours
  • Spinal infections or inflammation
  • Spinal stenosis
  • Major injuries to the lower back
  • Spinal arteriovenous deformities
  • Spinal haemorrhages
  • Spinal surgery complications
  • Spinal anaesthesia

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  • Cauda Equina Syndrome affects 1-3 people per 100,000 population in England and there are around 8,000 suspected cases every year. Up to two people in every 100 with herniated lumbar discs may develop the condition. (source)
  • 20% of litigated claims for spinal surgery in England between 2013/15 -15/16, related to Cauda Equina Syndrome. (source)
  • Current guidelines indicate that the outcome of surgical decompression is better if it occurs within the first 48 hours after the onset of symptoms. (source)

Symptoms and Diagnosis

Symptoms, or red flags, of Cauda Equina Syndrome may include:

  • Severe lower back pain
  • Weakness burning, prickling, tingling or numbness in the lower limbs
  • Sciatica-like pain in one or both legs
  • Difficulty walking
  • Alteration in urinary function, such as difficulty urinating or reduced flow
  • Loss of bladder or bowel control
  • Saddle anaesthesia (buttocks, anus and genitals)
  • Sexual dysfunction
  • Other neurological deficits

If suspected, immediate medical attention is crucial to prevent permanent damage and improve the chances of recovery.

Doctors will gather the patient’s history and perform a physical examination. Imaging tests such as a CT, MRI or a myelogram should be arranged as soon as possible within the first 24 hours.

Bladder scanning for residual urine after emptying and lack of catheter sensation can also help doctors confirm compression of the cauda equina nerves. Following diagnosis, urgent surgery should be carried out to remove the structures that are compressing the cauda equina.

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