Cauda Equina Syndrome
Doctor Instruction:
You are currently a senior surgical doctor on call. Your next patient is a 45-year-old gentleman, Adam, who presents back pain after being hit by a slow-moving car yesterday. Please take a history and perform an appropriate examination.
Patient History:
Adam, a 45-year-old gentleman, banker
You came in today following a small car collision towards your back while walking across the road last night. You brushed this off – thinking it was no big idea. However, you started noticing lower back pain with weakness in your lower limbs.
Back pain is located centrally in the lower back – can sometimes radiate down both legs. You describe the pain as sharp, rating it 10/10. You tried many things to ease the pain without success e.g. paracetamol and ibuprofen. Back pain can be triggered by simple back movement but not worsened by coughing or straining. You have numbness and tingling sensation running down both of your legs.
Also, while wiping yourself afterwards in the toilet, you couldn’t feel the sensation around your bottom as well as your genitals– it was very strange, and at that point, you knew you needed to go and seek medical attention. You developed incontinence for passing urine and faeces. You no longer have the urge to go the toilet, and they can come out involuntarily, which is very concerning for you—no other previous back injuries.
Idea, Concern, Expectation:
You have no idea what is going on, but you think it is related to yesterday's injury. You are very concerned and don’t want to be paralysed – you are still very young! You would like to find out what is going on. You are very scared if you need any surgery for this.
Past Medical History:
Hypertension, obesity
Drug History:
Ramipril, Atorvastatin
NKDA
Family History:
Ankylosing Spondylitis
Social History:
Smoke 10 cigarettes/day for over 20 years
Drink around 2-3 pints of beer every weekend
Work as a banker
Live with a wife and two kids in a semi-detached house
Examination Findings:
Both lower limbs power 4/5 with reduced sensations, tone, and reflexes.
Lower back spinal tenderness at L3/4 region.
PR Examination: Reduced anal tone and sensation.
No upper motor neurone signs
Differentials:
Caudal Equina Syndrome caused by trauma
Prolapsed lumbar disc
Conus medullaris syndrome
Mechanical back pain
Peripheral neuropathy
Spinal tumour
Investigations:
Basic observations
Routine bloods for baseline and pre-assessment e.g. FBC, U&Es, LFT, Bone Profile, CRP
Consider blood culture if suspected infection.
Emergency MRI to confirm and exclude cauda equina syndrome
Consider CT myelography/spine
Consider XR spine
Consider Urodynamic studies -to monitor bladder function
Management (Cauda Equina Syndrome):
Hospital Admission
VTE prophylaxis
Prevention of further damage e.g. Immobilise spine if CES is due to trauma
Neurosurgical input for consideration of lumbar decompression surgery – the earlier this is performed, the higher the chance of regaining functions.
Surgery may involve removing bone fragments, tumour, herniated disc, blood, debulking for SOL e.g. tumour abscess…etc.
Anti-inflammatories such as steroids, if due to inflammatory cause
For infectious causes, patients should be treated with antibiotics
Postoperative care includes physiotherapy, occupational therapy, and addressing lifestyle issues e.g. obesity.
Treatment for metastatic spinal cord compression includes analgesia, high-dose dexamethasone, surgery, radiotherapy, and chemotherapy. Investigations include biopsy, staging CT, PET scan…etc.
Viva Questions:
Explain the pathophysiology of cauda equina syndrome.
Cauda equina syndrome is caused by compression of nerve roots at the base of the spine. This pressure leads to severe back pain, leg pain, numbness, weakness, and bladder/bowel dysfunction.
Why is cauda equina syndrome a surgical emergency?
Cauda equina syndrome is a surgical emergency because the compression of nerve roots can cause permanent and severe neurological damage. Prompt surgery is essential to prevent irreversible loss of sensation, muscle function, and bladder/bowel control. The urgency is to minimize lasting deficits and improve patient outcomes.
Where does the spinal cord terminate (at what level)?
The spinal cord typically terminates around the level of the first or second lumbar vertebra (L1-L2) in most adults. Below this point, the spinal cord transitions into a bundle of nerve roots known as the cauda equina, which continues down the vertebral canal and provides innervation to the lower extremities and pelvic organs
What is conus medullaris?
The conus medullaris is the tapering, lower end of the spinal cord. It is located at the termination of the spinal cord, usually around the level of the first or second lumbar vertebra (L1-L2). Below the conus medullaris, the spinal cord transitions into the cauda equina, a bundle of nerve roots that extend further down the spinal canal. The conus medullaris is an important anatomical landmark and holds significance in medical imaging, surgical procedures, and discussions related to spinal cord and neurological health.
What are the causes of cauda equina syndrome?
Cauda equina syndrome is caused by conditions that compress or damage the nerve roots at the base of the spinal cord. Common causes include herniated discs, spinal tumors, spinal stenosis, trauma, infections, inflammatory conditions, and postoperative complications. Immediate medical attention is crucial to prevent permanent nerve damage.
Does cauda equina syndrome show lower or upper motor neurone signs or both?
Cauda equina syndrome leads to signs and symptoms characteristic of lower motor neuron involvement. These include bilateral reduction in sensation of the lower limbs, impaired bladder and bowel function, weakness in the lower limb muscles, intense back pain, and potential issues with sexual function.
