The most common cause of cauda equina syndrome is a herniated disk.
Cauda equina syndrome causes severe pain in the lower back, urinary problems (such as incontinence). and loss of sensation in the buttocks, genital area, bladder, and rectum.
Doctors immediately evaluate people with symptoms of cauda equina syndrome and do magnetic resonance imaging or computed tomography to confirm the diagnosis.
Surgery is often needed to relieve pressure on the cauda equina, and pain relievers and corticosteroids are used to relieve pain.
A bundle of nerves extends downward from the bottom of the spinal cord, through the lower back bones (vertebrae) and over the bone at the base of the spine (sacrum). This bundle is called the cauda equina, which means horse’s tail in Latin, because that is what the bundle looks like. The symptoms that result from compression of or damage to the cauda equina are called the cauda equina syndrome.
Cauda Equina Syndrome
A bundle of nerves extends downward from the bottom of the spinal cord, through the lower back bones (vertebrae) and over the bone at the base of the spine (sacrum). This bundle is called the cauda equina, which means horse’s tail in Latin, because that is what the bundle looks like. The cauda equina may be compressed by a ruptured or herniated disk, a tumor, or an abscess. It may be damaged by an injury or swell because it becomes inflamed (as occurs in ankylosing spondylitis). The symptoms that result are called the cauda equina syndrome.  |
Causes
The most common cause of cauda equina syndrome is
A ruptured or herniated disk Herniated Disk A herniated disk occurs when the tough covering of a disk in the spine tears or ruptures. The soft, jelly-like interior of the disk may then bulge out (herniate) through the covering. Aging... read more
in the lower spine, especially in people who are born with a narrow spinal canal
Other causes include the following:
Birth defects of the spinal cord Neural Tube Defects and Spina Bifida Neural tube defects are a certain type of birth defect of the brain, spine, and/or spinal cord. Neural tube defects can result in nerve damage, learning disabilities, paralysis, and death. The... read more (such as spina bifida Spina bifida Neural tube defects are a certain type of birth defect of the brain, spine, and/or spinal cord. Neural tube defects can result in nerve damage, learning disabilities, paralysis, and death. The... read more )
Infection of the tissues (meninges) that cover the cauda equina and spinal cord
An abscess (a collection of pus) pressing on the cauda equina
Spinal stenosis Lumbar Spinal Stenosis Lumbar spinal stenosis is narrowing of the spinal canal in the lower back. The narrowing squeezes (compresses) the nerves that travel through the lower back into the legs. Osteoarthritis, injuries... read more
(narrowing of the passageway that contains the spinal cord) in the lower backArteriovenous malformation (an abnormal connection between arteries and veins) in the lower back
Complications after surgery on the spine
Some of these conditions cause inflammation and/or swelling, putting pressure on the nerves. A tumor can put direct pressure on the cauda equina.
Symptoms
People with cauda equina syndrome may have severe pain in the lower back, usually due to the disorder causing cauda equina syndrome. People may lose sensation in the buttocks, genital area, bladder, and rectum—the area of the body that would touch a saddle (called saddle anesthesia). That is, these people may be less able to feel pain, touch, temperature, and vibration in these areas.
Sensation and muscle control may be impaired in the lower legs.
Other symptoms of cauda equina syndrome may include the following:
Loss of reflexes in the knee and ankle
Problems walking
Without treatment, cauda equina syndrome can cause complete paralysis of the legs.
Diagnosis
A doctor's evaluation
Imaging tests
Doctors suspect cauda equina syndrome based on symptoms and results of a physical examination. However, symptoms tend to vary.
Magnetic resonance imaging (MRI) is done immediately when cauda equina syndrome is suspected. If MRI is unavailable, myelography Myelography Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Electroencephalography (EEG) is a simple, painless procedure in which... read more 
with computed tomography (CT) is done. These tests can usually confirm the diagnosis.
Treatment
Surgery
Usually corticosteroids
People who have cauda equina syndrome require immediate medical attention.
Doctors focus on treating the disorder causing cauda equina syndrome. For example, surgery is done immediately to relieve pressure on the cauda equina caused by a herniated disk. Such treatment can prevent permanent damage.
Nonsteroidal anti-inflammatory drugs (NSAIDs) or other pain relievers are used. If these drugs do not relieve the pain, corticosteroids, given by mouth or injection, may help. Corticosteroids can also reduce swelling.
How well a person recovers often depends on the cause and how promptly it are treated. Symptoms are more likely to lessen or go away if the cause is identified and is treated immediately.
