Cauda equina syndrome is a serious medical condition caused by the compression of a bundle of nerves (called the cauda equina) at the bottom of the spinal cord. These nerves supply the bladder, bowel, skin around the anus, and the legs.
It is a rare condition that is often caused by a slipped disc (vertebral disc prolapse). It can also be caused by other changes to the spine, such as a narrowing of the space around the spinal cord (spinal stenosis), infection and cancer.
Cauda equina syndrome needs fast treatment because it can cause permanent nerve damage. This usually involves emergency surgery to relieve nerve compression.
If you think you have cauda equina syndrome, or you are unsure, you should see your doctor immediately or go to the nearest hospital.
In most cases, symptoms of cauda equina syndrome develop suddenly and tend to progress quickly. However, the symptoms can sometimes develop slowly. Lower back pain is common, but not everyone with the condition will experience back pain.
Other symptoms of cauda equina syndrome include:
- pain, numbness, or tingling in the lower back spreading down one or both legs (sciatica)
- bladder problems – you may find you are suddenly unable to pass urine or you lose control of your bladder
- bowel problems – such as constipation or inability to control your bowel movements
- sexual problems – this includes erectile dysfunction in men
- leg weakness – this may involve one or both legs, and you may notice you are unable to hold your foot up (foot drop)
- the area around your anus and/or genitals may feel numb (saddle numbness)
A slipped disc (prolapsed or herniated disc) is the most common cause of cauda equina syndrome.
There are many other causes, which include:
- narrowing of the nerve passages in the spine (lumbar spinal stenosis)
- inflammation or infections, such as meningitis and tuberculosis
- a collection of pus between the outer covering of the spinal cord and the vertebral column (epidural abscess)
- spinal birth defects, such as spina bifida
- spinal tumours, either originating within the spine or secondary deposits from another cancer (metastases)
- complications from medical procedures such as anaesthesia injections or spinal surgery
- inflammatory joint and muscle conditions, such as rheumatoid arthritis and ankylosing spondylitis
- serious back injuries, such as gunshot or stab wounds
- spinal (vertebral) fractures
- pooled blood within or around the spinal cord (spinal haematoma)
Your doctor may suspect cauda equina syndrome based on your symptoms and an examination.
As cauda equina syndrome needs immediate treatment, your doctor will usually refer you to a hospital as an emergency.
You will most likely have an MRI scan to confirm the diagnosis. Sometimes, a CT scan may be recommended, or you may have bladder control tests.
Cauda equina syndrome is a serious condition that needs urgent treatment to remove the cause and reduce the risk of permanent nerve damage.
In most cases, you will need emergency surgery to relieve the pressure on the nerves known as spinal decompression surgery (ideally within 48 hours).
If the underlying cause is an infection, you may need antibiotics. If a tumour is responsible, you may need radiotherapy or steroids to provide pain relief.
Living with cauda equina syndrome
If your treatment was successful, you may notice an improvement in your symptoms over time. However, in some cases, treatment for cauda equina syndrome may not restore your bladder, bowel and sexual function to how it used to be or the nerve damage may have left permanent changes.
It can be physically and emotionally challenging to adjust these changes. Your doctor may be able to offer advice and refer you to useful services and specialists, such as physiotherapists, occupational therapists or sex therapists.
You may be recommended strategies to help you manage your symptoms, such as:
- using a catheter to help you completely empty your bladder
- using glycerine suppositories or enemas to help empty your bowels to reduce the risk of unexpected leaks
- medicines for erectile dysfunction
Joining a cauda equina support group may help you gain support from others who have had similar experiences.
To find answers to any other health questions you might have, visit our Health A-Z.
The risk of developing cauda equina complications depends on the cause and how quickly you receive medical attention. Delayed diagnosis and/or treatment of the condition can increase your risk of permanent nerve damage, affecting the bladder, bowel, legs and genitals.
This may lead to various complications, including: