Although low back pain is common and usually goes away without surgery, cauda equine syndrome, a rare disorder affecting the bundle of nerve roots (cauda equina) at the lower (lumbar) end of the spinal cord, is a surgical emergency.

An extension of the brain, the nerve roots send and receive messages to and from the pelvic organs and lower limbs. Cauda equina syndrome occurs when the nerve roots are compressed and paralyzed, cutting off sensation and movement. Nerve roots that control the function of the bladder and bowel are especially vulnerable to damage.

If patients with cauda equina syndrome do not get fast treatment to relieve the pressure, it can result in permanent paralysis, impaired bladder and/or bowel control, loss of sexual sensation, and other problems. Even with immediate treatment, some patient may not recover complete function.

Cauda equina syndrome may be caused by a ruptured disk, tumor, infection, fracture, or narrowing of the spinal canal. It may also happen because of a violent impact, such as a car crash, a fall from significant height, or a penetrating injury, such as a gunshot or stabbing injury. Children may be born with abnormalities that cause cauda equina syndrome.

Although early treatment is required to prevent permanent problems, cauda equina syndrome may be difficult to diagnose. Symptoms vary in intensity and may evolve slowly over time.

See your doctor immediately if you have:

• Bladder and/or bowel dysfunction, causing you to retain waste or be unable to hold it.
• Severe or progressive problems in the lower extremities, including loss of or altered sensation between the legs, over the buttocks, the inner thighs and back of the legs (saddle area), and feet/heels.
• Pain, numbness, or weakness spreading to one or both legs that may cause you to stumble or have difficulty getting up from a chair.

To diagnose cauda equina syndrome, the doctor will probably evaluate your medical history, give you a physical examination, and order multiple diagnostic imaging studies.

If you have cauda equina syndrome, you may need urgent surgery to remove the material that is pressing on the nerves. The surgery may prevent pressure on the nerves from reaching the point at which damage is irreversible.