Chronic low back pain continues to perplex and confound patients and health care providers alike. The field of health care is now calling for treatment based on scientific evidence of its effectiveness. Groups of experts are getting together to search the literature for enough evidence to support one treatment over another.
Recently, a large multidisciplinary panel of back pain experts was gathered together by the American Pain Society. Their task? Review all published randomized trials looking for evidence to help them draft some guidelines for the treatment of chronic low back pain. Efforts of this type are appreciated by those who work with chronic low back pain patients. Instead of everyone spending hours sorting through all the studies trying to make sense of them, experts in the field get together and perform the task, making summary recommendations for all to use.
This group focused on three areas: interventional diagnostic tests and therapies, surgery, and rehabilitation. Interventional refers to more invasive efforts to find out if specific musculoskeletal structures (e.g., joints, disc, muscles, ligaments) are causing the patient’s pain. The theory is that if areas can be targeted as the main cause of the problem, then more effective treatment can be directed at that area.
Since back pain can be caused by a wide range of anatomic and psychologic problems, this study limited the patient populations studied to those who had nonradicular low back pain, radiculopathy with herniated disc, and spinal stenosis. Nonradicular low back pain refers to back pain caused by something other than pressure on (or irritation of) the spinal nerve roots.
Radiculopathy is the leg pain and/or numbness and tingling that comes from chemical irritation or mechanical compression of the spinal nerve root. In this particular diagnosis, the source of that pain is a herniated disc affecting the nerve root. Spinal stenosis is a narrowing of the spinal canal, the long, narrow tube formed by the vertebrae through which the spinal cord travels from the brain down to the lumbar spine.
The guideline panel got together knowing two things: 1) a small number of people who develop chronic low back pain (probably five per cent) account for 75 per cent of all the money spent on low back pain and 2) management of this chronic problem is complex and requires a shared decision-making process by many people (including the patient, family, and the various members of the multidisciplinary team).
They came out of the review process with eight strong recommendations. The evidence reviewed showed a clear benefit of some treatment approaches that was greater than any potential harm or burden. Types of interventional treatments reviewed included prolotherapy, steroid injection (into the disc or joint), BOTOX injection, radiofrequency denervation, and spinal cord stimulation. Surgery to remove problematic structures such as the disc or lamina (bone over the disc) was also included in the evaluation. The procedures investigated were specific to each of the three diagnostic categories.
The 23 panel members worked together for two full years. When they voted on each recommendation, two-thirds had to agree or the guideline would not be adopted. There was complete agreement on all but recommendations number 1,2, and 3, and there was only one dissenting vote on those. Here is a brief summary of each recommendation.
Recommendation 1. Discography may show signs of degenerative disc disease, but that doesn’t mean the patient’s pain is coming from the disc. Therefore, provocative discography is not recommended. During discography, contrast medium is injected into the disc and the patient’s response to the injection is observed. In theory, pain that is similar to the patient’s current back pain suggests that the disc might be the source of the pain. But there are too many false positives to trust the test. And patients with a positive test who had surgery didn’t have better results than those who didn’t have surgery.
Recommendation 2. Anyone with chronic low back pain who has not gotten better with conservative (nonoperative) care should be managed by a team of clinicians especially including a psychologist or behavioral specialist. This is called interdisciplinary rehabilitation. Best results occur when cognitive/behavioral therapy is combined with a prescriptive and supervised exercise program.
Recommendation 3. The evidence does not support injections with BOTOX, steroids, and prolotherapy. Nerve blocks, intradiscal electrothermal therapy (IDET), and intrathecal therapy with narcotics or other opioid medications can’t be recommended either based on the data available so far. There just isn’t enough evidence to support the use of injections or other interventional therapies. Either the evidence was insufficient or the results were no better than when sham treatments were given.
Recommendation 4. Nonradicular back pain responds as well to conservative (nonoperative) care as it does to surgery, so surgery should be considered a low-priority option. Patients considering surgery should be told about the risks and possibility that the results will be less than satisfactory. Intensive interdisciplinary rehabilitation is always recommended first before surgery.
Recommendation 5. Artificial disc replacements still aren’t proven better than spinal fusion. Yes, they preserve motion at the involved vertebral level. But they can loosen and migrate or sink down into the bone causing problems. Patients may end up getting a fusion when the device fails. And just like with a fusion, patients with disc replacements still develop facet (spinal) joint arthritis and degenerative changes at the adjacent (next) vertebral level.
Recommendation 6. Steroid injections for radiculopathy due to disc herniation give short-term relief only. There are no long-term benefits of this treatment. There isn’t enough evidence to recommend or reject this treatment for spinal stenosis. If one injection doesn’t do the trick, should another be given? What’s the best timing for injection(s)? These questions still haven’t been answered fully yet (insufficient evidence).
Recommendation 7. Anyone thinking about spinal surgery for herniated disc or spinal stenosis should know that pain relief is possible in the short-term. But the final results (one to two years later) aren’t any different with or without the surgery. So, the cost of the procedure and possible risks should be factored against the possible short-term benefits before going ahead with the operation. There is still much to be studied when comparing one type of surgery over another. Timing of surgery and patient selection are two other factors that might make a difference but for which there isn’t enough data to make recommendations.
Recommendation 8. What can be done for patients who have had unsuccessful back surgery? This is called failed back surgery syndrome. Spinal cord stimulation may be an option. The risks associated with this treatment (e.g., infection, device-related problems, wound breakdown) must be weighed against the benefits for each candidate. Studies are needed to compare spinal cord stimulation with intensive interdisciplinary rehabilitation.
The authors conclude that these guidelines may not apply to each and every patient. There are always reasons why one patient might be different and need additional consideration. Clinicians can use the guidelines to explain the treatment approach they recommend. The American Pain Society plans to review and update the guidelines on a regular basis. Health care providers working with chronic low back patients can look for the next updates by 2012.
In many areas, there is still insufficient evidence to even form guidelines. More study is needed. Having a summary like this of what has been discovered so far and what’s left to explore will be very helpful for researchers planning future studies.