Preventing Back Pain in Working Adults
If we could find a way to prevent back pain, it would save many people the pain of the condition as well as the expense of treatment. Many studies have been done trying to find a successful answer to back pain prevention. In this study, researchers from the Department of Orthopedic Surgery at the University of Washington in Seattle took the time to review high-quality studies to see what might be working.

They looked for controlled trials, which means one group of patients receives the treatment. Then the results are compared with a second (control) group who do not receive the treatment. They found 185 possible studies. But when they looked a little closer, only 20 were acceptable. And even within those 20 studies, the patient populations were so heterogenous they couldn't do a systematic review.

What do all these research terms mean? Heterogenous refers to the fact that the patients from study to study were different enough that it was like comparing apples to oranges. Various factors in the studies were also too different to make comparisons. Experts say for better (more high-quality) research, the patients in each group should be more homogenous (alike) than different.

The bottom-line was that this group of authors could not use the combined results of all the studies together to perform a systematic review. Systematic reviews can be helpful when studies are too small to really give significant results. Adding them all together creates a bigger pot from which to draw conclusions. But again, if the pot is too full of different ways to approach the problem, then this type of review can't be done.

Having said all that, what kind of studies were included and what did they find? First, only adult patients (ages 18 to 65) with similar types of back pain were included. Anyone with a medical cause of back pain such as a tumor, infection, or fracture was not included. That helped create a group of homogenous patients. The follow-up period was at least six months. And statistical analysis was done properly.

Types of prevention techniques included patient education, exercise, braces, and orthotics (shoe inserts). Changes in work policies and activity modification (work and recreation) were also included. A final category included ergonomic equipment. This would include anything that helped people reduce the workload or reduce stress on the back.

In order to compare results of studies, the outcome measures have to be reported in similar ways from group to group. Types of outcome measures allowed in this study were objective (e.g., number of sick days due to back pain, medical costs, work injury claims) and subjective. The subjective measures were geared around what the patients could remember about their back pain (e.g., how often symptoms occurred, how intense was the pain, type of limitations or disability experienced).

The authors carefully explain how they conducted their literature search, how they evaluated the studies they found, and how they rated the strength of the evidence they reviewed. They provided the reader with extensive and detailed tables summarizing the results of each treatment approach. In the end, what they found was that exercise was the most effective in preventing low back pain.

Things like back supports, shoe inserts, stress management, and back education had no effect on reducing or preventing the incidence of back pain in working adults. Reduced lifting programs had no effect either. So, what kind of exercise is best?

Most of the studies focused on abdominal and back extensor muscle strength, power, and flexibility. The most successful exercise programs were supervised, consisted of 45 to 60 minute sessions, and took place twice a week. The length of time patients met ranged from three months to a full year. The patients in the exercise groups had stronger abdominal and back muscle strength. They also had much lower work absence (28 days) compared with control groups (155 days) over the same period of time (13 months).

Over the past few decades, employers, individuals, and communities have spent large amounts of time and money in an effort to prevent back pain in working adults. And they have continued to do so without any real proof that what they were doing was working. This is the first study to step back and take a look at high-quality research studies and report on their findings.

It appears that exercise programs of all kinds work best. There seems to be a general benefit to exercise that results in reduced episodes of low back pain and fewer days lost at work when back pain does occur. What's the explanation for this? It's not clear yet if there is a simple answer.

There may be ways in which exercise affects the body that go beyond the biology. Maybe people feel more confident after exercising. The results are reflected in their general health including reducing incidents of back pain. Maybe they are less fearful of injury and somehow this lends to lower episodes of such injuries.

What the authors know for sure from this systematic literature review is that well-designed, quality trials are needed to continue testing out new ways to prevent low back pain. Using work absence and function seems to be a good way to sort out what works and what doesn't.

It's possible that combining two or more prevention techniques would have even better results than exercise alone. There's no proof for this at the present time. Further studies are needed to sort out where our resources should go to prevent low back pain in different homogenous groups of people.
Stanley J. Bigos, MD, et al. High-Quality Controlled Trials on Preventing Episodes of Back Problems: Systematic Literature Review in Working-Age Adults. In The Spine Journal. February 2009. Vol. 9. No. 2. Pp. 147-168.