Building an understanding of back pain, a common but poorly understood condition

The Cochrane Back Review Group, hosted at IWH, celebrates 15 years of synthesizing and assessing research on neck and back pain

It’s difficult for people to understand how debilitating back pain can be until they experience it. Andrea Furlan had a first-hand encounter with it last spring, and despite her many years of researching and treating the condition, the episode was eye-opening.

The pain was constant. It was hard to sit, but it was also hard to move, says Dr. Furlan, an associate scientist at the Institute for Work & Health (IWH) and the new coordinating editor at the Cochrane Back Review Group. She had to keep a sense of panic in check. Once she ruled out more serious problems by completing a diagnostic tool, she tried not to think of the pain in catastrophic terms.

I had to remind myself that the acute pain will eventually go away, says Furlan. I knew this, but it didn’t make it feel better.

The episode was a powerful reminder of the potentially life-altering impact of the pain. Back pain is one of the most common health problems in industrialized countries, but it’s also very misunderstood. About eight in 10 people in industrialized countries are expected to experience low-back pain—the most common kind—at some point in their lives.

Pain in the lower back is sometimes caused by an ordinary activity—in Furlan’s case, coughing too hard. In most cases, it goes away after a couple of weeks. But about 10 to 15 per cent of the time, the pain lingers for months, potentially developing into chronic pain. And in some people, the pain comes back again and again over the years, for no clear reason.

Clinicians still know very little about why or how acute pain becomes chronic pain. And once the pain becomes chronic, they know very little about how to treat it. In addition to that knowledge gap—or perhaps because of it—there’s a real tendency on some patients’ parts to perceive the pain as a lifelong disabling condition.

Overtaken by discomfort, people with low-back pain will often consider an array of treatments—including some with questionable evidence. As one retired nurse from Hamilton, Ont. puts it, I’ve tried physiotherapy, exercise, acupuncture, a TENS unit, a body cast. If it was available, I’ve tried it. I will admit I even had a laying on of hands.

To Furlan and her fellow researchers at the Cochrane Back Review Group (informally referred to as the Back Group), that desperate need among patients and clinicians for guidance about how to treat or cope with back pain is what drives their research agenda. Celebrating its 15th anniversary this year, the Back Group was set up to bring forward evidence-based health interventions for neck and back pain and other types of spinal disorders (though fractures and inflammatory diseases are outside its scope).

Hosted by IWH in Toronto, the Back Group is one of 53 groups that make up the Cochrane Collaboration. The Collaboration is an international effort to improve health care by shining a light on the best evidence available. It, too, is celebrating an anniversary this year—its 20th.

In the early years, our work was very much about sorting through the weaknesses in the literature on this condition, says IWH Senior Scientist Dr. Claire Bombardier, who co-founded the Back Group along with the world-renowned Swedish orthopedic surgeon, Dr. Alf Nachemson. The literature at the time was very compartmentalized. It had a very surgical approach, and many of the randomized controlled trials that were done at the time didn’t have high quality methodology.

The bread and butter of Cochrane groups are systematic reviews. These research studies are conducted according to a format designed to be as scientifically rigorous as other forms of research such as experiments and trials.

In a systematic review, researchers set out with a clear question—“What’s the effectiveness of intervention X on those with condition Y?”—and thoroughly search the scientific literature for the best available evidence on that question. They then review the studies carefully to grade each for the quality of the study design (were there control groups?), the strength of its findings (might there be other explanations for the results?) and so on.

The goal is to synthesize the available research for a wide audience—patients, clinicians, policy-makers and other scientists—and give them a sense of what works and what doesn’t. The reality tends to be less black and white, says Furlan, who took over from Bombardier this fall as coordinating editor for the group. It’s not often that systematic reviews can say in a sweeping manner whether a given intervention works. It might work for a subset of patients but not another. Or it might work in the short term but not the long run.

Most of the interventions we’ve reviewed don’t fall into black and white boxes. They fall into a grey box in the middle. But even that is helpful, says Furlan. It’s helpful to patients and clinicians to know which treatments are in the grey zone, because it means that they could still try them. An intervention that doesn’t work for one person may still work for someone else.

That’s not to say there’s nothing in the black and white boxes. Several strong recommendations have emerged out of the group’s work (see sidebar). The group has also looked at several treatments that are sometimes viewed with skepticism and not found evidence against them.

If you look at the systematic reviews of spinal manipulation and acupuncture, the findings don’t show that these interventions are any worse than others. They also don’t show that they are any better, says Dr. Maurits Van Tulder, a health technology assessment professor at the VU University Medical Centre and the VU University in Amsterdam who shares the coordinating editor role with Furlan. Many patients will seek these interventions out anyway, especially if their symptoms don’t improve, he adds.

The public needs to understand that inconclusive systematic review findings often stem from the fact that too few randomized controlled trials have been done to answer the question being asked by the systematic review. But that’s changing, says Van Tulder. In just the 15 years he’s been involved with the Back Group, Van Tulder has seen a rise in the number of randomized controlled trials. It’s a sign that appreciation for evidence-based health care is growing.

The scope of the group’s work is also expanding. In the early years, Back Group reviewers focused mainly on intervention treatments, and relatively little work was done on ways to diagnose and predict the outcome of the condition.

The reason for that, says Furlan, is that the way to measure the effectiveness of interventions—namely, through randomized controlled trials—tends to be more straightforward and easier to assess for quality. By contrast, studies of causes and prognoses are more varied in design. Plus, they require more time and resources to do, particularly if they involve longitudinal or follow-up studies. As a result, fewer of these studies are out there for reviewers to synthesize.

Nevertheless, the Back Group is starting to tackle different types of reviews. Furlan is now reviewing studies on opioid treatments to look for adverse outcomes. The group is also starting to assess the effectiveness of interventions in relation to cost—a real-world concern that hasn’t always been reflected in the scientific literature.

The thinking about back pain has evolved tremendously, says Bombardier. Increasingly, researchers and clinicians are starting to view back pain not as a one-time occurrence but as a recurring condition. From that perspective, researchers will need to do more long-term follow-up work to understand the different patterns of recurrence experienced by patients. Most of the trials currently aren’t taking this into account.

Furlan knows that, to the non-scientific world, progress on back pain may seem slow. She is optimistic, however, that the work of building evidence will matter over time.

Even now, she continues to hear radio ads publicizing the use of traction to treat back pain, which she knows doesn’t work for most people. Knowing how people with back pain can be vulnerable to any kind of pitch, Furlan hopes that the work of the Cochrane Back Review Group will one day filter through to the public at large.

For more information on the Back Group, go to: www.back.cochrane.org. See also the editorial marking the group’s 15th anniversary in the November 2013 issue of the medical journal, Spine.

Source: At Work, Issue 74, Fall 2013: Institute for Work & Health, Toronto

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