Spotlight on Research for 2006

December 2006 (historical)

Study Shows Patients With Herniated Disks Improve Over Time - Even Without Surgery

A new study supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), a part of the National Institutes of Health, gives doctors and patients reason to reconsider surgery when planning treatment for herniated disks. In the 13-center study of candidates for lumbar diskectomy, researchers found that those who forwent surgery for nonoperative care fared similarly to those who had the surgery. In general, surgery patients experienced slightly more improvement over the study period, and particularly in the first 3 months, than those who opted for other treatments.

Lumbar diskectomy - the surgical removal of all or part of an intervertebral disk - is the most commonly performed surgical procedure for patients having back or leg pain. Intervebral disks are cartilage-like structures situated between the individual bones, or vertebrae, of the spine. Each disk consists of a tough outer coating and jelly-like filling that helps absorb shock from the body's movement. However, when a disk protrudes from its normal position, it can place pressure on surrounding nerves, causing pain in the back as well as down one or both legs. While removing the disk is often effective in alleviating the associated pain, there has been little research to support the surgery's effectiveness over other therapies. Thus, the optimal treatment for herniated (slipped) disks has not been clear.

To better understand the role of surgery in this situation, NIAMS-supported researcher James N. Weinstein, D.O., of Dartmouth Medical School and his colleagues compared the outcomes of surgical and nonoperative treatments for herniated disks of the lumbar (lower) spine. Their study, the Spine Patient Outcomes Research Trial (SPORT), uniquely included both a randomized trial study group (i.e., the participants were chosen at random to have surgery or nonsurgical treatment) and an observational study group who chose their own treatment.

In the randomized portion of the study, 472 patients with confirmed herniated lumbar disks along with pain radiating from the spine lasting for at least 6 weeks were divided into two groups. The first group, 232 patients, was assigned to undergo diskectomy. The second group, 240 patients, was selected for nonoperative treatment. This included at least active physical therapy, education/counseling with home exercise instruction, and nonsteroidal anti-inflammatory drugs such as ibuprofen and naproxen, if the patient could tolerate them. Other treatments some patients received included medications such as narcotic analgesics, epidural steroid injections and muscle relaxants and treatment with devices such as braces, orthopaedic pillows and shoe inserts. The doctors then followed up on the patients at 6 weeks, 3 months, 6 months and 1 and 2 years.

Unfortunately, a comparison of the two groups wasn't as easy as hoped. The researchers found that only half of the patients who had been selected for surgery actually had surgery within 3 months, while almost one-third of those selected for nooperative treatments also had surgery.

While patients in both groups improved substantially over the first 2 years, their deviation in many cases from their assigned treatment made it challenging for the researchers to determine the reason for their improvement. Also, while the surgery group tended to experience slightly more improvement than the nonsurgery group, the fact that many in the surgery group did not have surgery and many in the nonsurgery group did have surgery made it impossible to establish the superiority of surgery as a treatment for herniated disks.

The observational portion of the study, however, showed some significant benefit of surgery over nonoperative treatments, at least in the short term. Of the 743 patients enrolled in this arm of the study, 528 received surgery and 191 received the usual nonoperative care. The benefits of surgery were seen as early as 6 weeks and were maintained for at least 2 years.

"While lumbar diskectomy is a common surgical procedure, its necessity in treating herniated disks has not been established," says Dr. Weinstein. Magnetic resonance imaging often reveals herniated disks in patients without symptoms, and some herniations regress in time without surgery, he says. Furthermore, a 15-fold variation in regional diskectomy rates in the United States and lower rates internationally in patients raise questions about the surgery's appropriateness in some cases. "This study is important in that it offers assurance that indeed, lumbar diskectomy is generally effective in relieving pain from herniated disks. It also offers assurance to patients who are able to wait out the pain that in time their symptoms will likely subside even without surgery."

NIAMS Director Stephen I. Katz. M.D., Ph.D., agrees. "Herniated disks are a common problem that cause significant pain and often disability," he says. "This study suggests that surgery may be an effective route to relief for many people, but that longer term, nonoperative therapies may offer benefits that are similar to if not equal for patients who cannot or elect not to have surgery."

Additional support for this research was provided by the NIH Office of Research on Women's Health and the National Institute of Occupational Safety and Health (NIOSH).

The mission of the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), a part of the Department of Health and Human Services' National Institutes of Health, is to support research into the causes, treatment and prevention of arthritis and musculoskeletal and skin diseases; the training of basic and clinical scientists to carry out this research; and the dissemination of information on research progress in these diseases. For more information about NIAMS, call the information clearinghouse at (301) 495-4484 or (877) 22-NIAMS (free call) or visit the NIAMS Web site at http://www.niams.nih.gov

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Weinstein JN et al. Surgical vs nonoperative treatment for lumbar disk herniation. JAMA:The Spine Patient Outcomes Research Trial (SPORT): A Randomized Trial. JAMA 2006;296:2441-2450.

Weinstein JN et al. Surgical vs nonoperative treatment for lumbar disk herniation: The Spine Patient Outcomes Research Trial (SPORT) Observational Cohort. JAMA 2006;296:2451-2459.