Cauda equina syndrome overview

Lower back pain is very common. It affects millions of people. In most cases, you don't need surgery for lower back pain. However, in rare cases, severe back pain can be a sign of cauda equina syndrome (CES), a condition that usually requires urgent surgical treatment. People with cauda equina syndrome are admitted to a hospital as a medical emergency. Here's what you need to know about cauda equina syndrome.

What is cauda equina syndrome?

Cauda equine syndrome is a rare disorder that is a medical emergency. In patients with cauda equina syndrome, something compresses the spinal nerve roots. You may need fast treatment to prevent lasting damage, leading to incontinence and possibly permanent paralysis of the legs.

CES affects a bundle of nerve roots called cauda equina (Latin for horse's tail). These nerves are located at the lower end of the spinal cord in the lumbar spine. They send and receive messages to and from your legs, feet and pelvic organs.

Causes of cauda equina syndrome

CES occurs more often in adults than in children, but it can occur in children who have a spinal birth defect or have had a spinal injury.

These are the most common causes of cauda equina syndrome:

• A herniation (bulging) of a spinal disk in the lumbar area that presses on the nerves (the most common cause).
• Narrowing of the spinal canal (stenosis).
• A spinal lesion or tumour.
• A spinal infection, inflammation, haemorrhage or fracture.
• A complication from a severe lumbar spine injury such as a car crash, fall or other traumatic injury such as a stabbing.
• A birth defect such as an abnormal connection between blood vessels (arteriovenous malformation).

Symptoms of cauda equina syndrome

It may be hard to diagnose cauda equina syndrome. Symptoms vary and may come on slowly. They also mimic other conditions. If you have any of these symptoms, seek medical advice right away:

• Severe lower back pain.
• Pain, numbness or weakness in one or both legs that causes you to stumble or have trouble getting up from a chair.
• Loss of or altered sensations in your legs, buttocks, inner thighs, backs of your leg, or feet that is severe or gets worse and worse. You may experience this as trouble feeling anything in the areas of your body that would sit in a saddle (called saddle anaesthesia).
• Recent problems with bladder or bowel function, such as trouble eliminating urine or waste (retention) or trouble holding it (incontinence).
• Sexual dysfunction that has come on suddenly.

Diagnosing cauda equina syndrome

If you develop any of the above symptoms, seek medical advice immediately  or visit the accident and emergency department of your nearest hospital.  Here's what you may need to confirm a diagnosis:

• A medical history, in which you answer questions about your health, symptoms and activity.
• A physical examination to assess your strength, reflexes, sensation, stability, alignment, and motion. You may also need blood tests.
• Magnetic resonance imaging (MRI) scan, which uses magnetic fields and computers to produce three-dimensional images of your spine.
• A myelogram - an X-ray of the spinal canal after injection of contrast material - which can pinpoint pressure on the spinal cord or nerves.
• A computed tomography (CT) scan.