Sciatica

• What is sciatica?
• What are causes of sciatica?
• How is sciatica diagnosed?
• How is sciatica treated?
• Sciatica At A Glance
• Related sciatica articles:
  Sciatica - on WebMD

What is sciatica?

Sciatica is pain resulting from irritation of the sciatic nerve. Sciatica pain is typically felt from the low back to behind the thigh and radiating down below the knee. The sciatic nerve is the largest nerve in the body and begins from nerve roots in the lumbar spinal cord in the low back and extends through the buttock area to send nerve endings down the lower limb.

What are causes of sciatica?

While sciatica is most commonly a result of a disc herniation directly pressing on the nerve, any cause of irritation or inflammation of this nerve can reproduce the symptoms of sciatica. These causes include irritation of the nerve from adjacent bone, tumors, muscle, internal bleeding, infections, injury, and other causes.

How is sciatica diagnosed?

Sciatica is diagnosed with a physical exam and medical history. The typical symptoms and certain examination maneuvers help the healthcare practitioner to diagnose sciatica. Sometimes, x-rays, films, and other tests, such as CAT scan or MRI scan and electromyogram, are used to further define causes of sciatica.

How is sciatica treated?

Bed rest has been traditionally advocated for the treatment of sciatica. But how useful is it?

To study the effectiveness of bed rest in patients with sciatica of sufficient severity to justify treatment with bed rest for 2 weeks, a research team in the Netherlands led by Dr. Patrick Vroomen randomly assigned 183 such patients to bed rest or, alternatively, to watchful waiting for this period.

To gauge the outcome, both primary and secondary measures were examined. The primary outcome measures were the global assessments of improvement after 2 and 12 weeks by the doctor and the patient. The secondary outcome measures were changes in functional status and in pain scores, absenteeism from work, and the need for surgical intervention. Neither the doctors who assessed the outcomes nor those involved in data entry and analysis were aware of the patients' treatment assignments.

The results, reported in the New England Journal of Medicine , showed that after 2 weeks, 64 of the 92 (70 percent) of the patients in the bed-rest group reported improvement, as compared with 59 of the 91 (65 percent) of the patients in the control (watchful-waiting) group. After 12 weeks, 87 percent of the patients in both groups reported improvement. The results of assessments of the intensity of pain, the bothersomeness of symptoms, and functional status revealed no significant differences between the two groups. The extent of absenteeism from work and rates of surgical intervention were similar in the two groups.

The researchers concluded that: "Among patients with symptoms and signs of a lumbosacral radicular syndrome, bed rest is not a more effective therapy than watchful waiting." Sometimes conventional wisdom is not as wise as research!

Other treatments for sciatica include addressing the underlying cause, medications to relieve pain and inflammation and relax muscles, and physical therapy. Surgical procedures can sometimes be required for persisting sciatica that is caused by nerve compression at the lower spine.

Sciatica At A Glance

• Sciatica is a nerve pain from irritation of the sciatic nerve.
• The sciatic nerve is the largest nerve in the body.
• Sciatica pain is typically felt from the low back to behind the thigh and radiating down below the knee.
• Treatments for sciatica depend on the underlying cause and the severity.

Reference: Patrick C.A.J. Vroomen, Marc C.T.F.M. de Krom, Jan T. Wilmink, Arnold D.M. Kester, J. Andre Knottnerus. Lack of Effectiveness of Bed Rest for Sciatica. N Engl J Med 1999; 340:418- 23.