Low back pain is common, and in most cases, it improves without surgery. But severe back pain can be a symptom of a serious condition that is not well known and is often misdiagnosed. Cauda equina syndrome (CES) occurs when the bundle of nerve roots at the lower end of the spinal cord (cauda equina) are compressed and disrupt motor and sensory function to the lower extremities and bladder. Patients with this syndrome are often admitted to the hospital as a medical emergency. CES can lead to incontinence and even permanent paralysis.
The collection of nerves at the end of the spinal cord is known as the cauda equina, due to its resemblance to a horse’s tail. The spinal cord ends at the upper portion of the lumbar (lower back) spine. The individual nerve roots at the end of the spinal cord provide motor and sensory function to the legs and the bladder. The cauda equina is the continuation of these nerve roots. These nerves send and receive messages to and from the lower limbs and pelvic organs.
Symptoms
The symptoms of cauda equina syndrome can vary, but the key signs doctors look for are:
- Severe low back pain and sciatica
- Pain may be sudden and severe or gradually develop over weeks
- Motor weakness, sensory loss, or pain in one, or more commonly both legs
- Difficulty to pass urine or use the bowels
- Prolonged inability to pass urine can result in urine leaking uncontrollably
- Numbness or tingling in the groin (“saddle region”)
- Sexual dysfunction
Causes
Cauda equina most commonly occurs when a disc in the back pushes out of place and compresses the spinal cord (see Disc Herniation). Usually this needs to be a severe herniation to cause cauda equina.
Other causes of cauda equina include:
- Spinal canal stenosis with a smaller disc prolapse
- Trauma to the spine
- Rare causes include infection in and around the vertebral bones (see osteomyelitis), cancer in the spine, after injections into the spine or spine surgery.
Risk Factors
Risk factors for developing cauda equina syndrome include:
- A history of low back pain with sciatica, especially sciatica in both legs.
- Instability or deformity of the spine
- Trauma to the spine, often following a car accident
- Recent lumbar spine surgery
- A history of cancer
- Recent severe infection
- Cauda equina syndrome can develop suddenly even without these risk factors.
Investigations
Complications
Complications are increasingly likely if diagnosis and appropriate management is delayed, and include residual:
- Paralysis
- Sensory abnormalities
- Bladder, bowel, and sexual dysfunction
Treatment
Seeking Advice
Your Family Doctor (GP)
Your Family Doctor will be able to diagnose and help treat your problem. He or she will be able to
- tell you about your problem
- advise you of the best treatment methods
- prescribe you medications
- and if necessary, refer you to Specialists (Consultants) for further treatment
Prevention
Prevention of cauda equina syndrome is focused on early diagnosis by identifying the symptoms described. While low back pain with leg pain and/or weakness is a common complaint that affects many people, cauda equina syndrome is a rare complication. Your doctors should be vigilant in identifying these cases. You should familiarise yourself with the signs and symptoms that could suggest possible cauda equina syndrome, including change in bowel or bladder function and loss of sensation in the groin.