Definition

Cauda equina syndrome (CES) is when the nerve roots at the base of the spinal cord are compressed. Known as the cauda equina, this bundle of nerves is responsible for the sensation and function of the bladder, bowel, sexual organs, and legs. CES is a medical emergency. If treatment is not started to relieve pressure on the nerves, function below the waist may be lost.

Causes

A common cause of CES is injury of a spinal disk on the nerve roots. A spinal disk is a semi-soft mass of tissue between the bones of the spine. These bones are known as the vertebrae. The disks act as the spine’s shock absorbers. When a disk spills out into the spinal canal, it can press against the bundle of nerves, causing CES. This syndrome may also be caused by:

• Accident that crushes the spine, such as a car accident or fall
• Penetrating injury, such as a knife or gunshot wound
• Arthritis, such as ankylosing spondylitis
• Complications from spinal anesthesia
• Mass lesion, such as a blood clot
• Complications from cancer
• Side effect of certain medications

Risk Factors

Factors that may increase your risk of developing CES include:

• History of back problems, such as lumbar spinal stenosis
• Degenerative disk disease
• Birth defects, such as a narrow spinal canal or spina bifida
• Hemorrhages affecting the spinal cord
• Arteriovenous malformation
• Spinal surgery or spinal anesthesia
• Lesion or tumor affecting the spinal bones, spinal nerve roots, or cerebrospinal fluid (CSF)
• Infection affecting the spine
• Manipulation of the lower back—rarely

Symptoms

Symptoms may include:

• Severe low back pain
• Numbness or tingling in the crotch area known as saddle anesthesia/paresthesia
• Inability to urinate, or to hold urine or feces
• Inability to walk or dragging of foot
• Weakness, loss of sensation, or pain in one or both legs
• Sexual dysfunction; in men, the inability to maintain an erection

Diagnosis

You will be asked about your symptoms and medical history. A physical exam will be done. A neurological exam, which includes testing reflexes, vision, mental status, and strength, may also be done. A rectal exam may be done to assess sphincter function.

Images may be taken of your bodily structures. This can be done with:

• MRI scan
• CT scan
• Myelogram

Your muscle activity may be measured. This can be done with electromyography.

Treatment

Talk with your doctor about the best treatment plan for you. Treatment options include the following:

• Surgery options:
  • Laminectomy —a surgical procedure to remove a portion of a vertebra, called the lamina
  • Diskectomy —a surgical procedure to remove part of an intervertebral disk that is putting pressure on the spinal cord or nerve root
• Radiation therapy —If CES is due to cancer, radiation therapy may be an option.

Your doctor may also treat the underlying cause of CES.

Prevention

There is no way to prevent CES.

Spinal Cord Resource Center—United Spinal Association http://www.spinalcord.org

Spinal Cord Injury Canada http://sci-can.ca

Cauda equina syndrome. EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed
Updated August 20, 2014. Accessed November 20, 2014.