Disability Prevention After Episode of Low Back Pain in Workers
Most adults who experience an episode of low back pain recover and return to work in a short amount of time. But problems develop for those who have chronic pain and have not gotten back to work after three months of sick leave. Rehab and pain specialists are trying to put together a short screening tool to help identify patients early on who are at risk for work disability.

In this study, 346 adults from Belgium who applied for compensation benefits because of chronic low back pain were studied. Since Belgium has a compulsory health insurance system, the number of working days lost and the cost of disabled workers adds up.

In a compulsory insurance system, everyone is required to take out health insurance, just as all drivers have car insurance. There are government tax subsidies to help the poorest pay for their insurance. In Belgium, the program also includes sickness benefits for patients who have stopped all activities because of an inability to work. This adds to the overall costs to society of back pain.

The first goal of the study was to find risk factors that might point to future delays in return to work status. A secondary goal was to put together the screening tool mentioned. You might think that the severity of the injury or back pain would be prognostic. But it's not. In fact, other studies show that factors that delay recovery from back pain tend to be psychosocial rather than medical.

For the majority of back pain patients, staying active and focusing on improving function rather than decreasing pain works well as a rehab model. Workers are advised to stay at work or modify activities and get back to work as soon as possible. But for those who don't respond to this approach, what would work better? And why doesn't this method produce good results?

All patients in the study were examined by a physician. The physical exam was an in-depth assessment of the neurologic, muscular, and skeletal systems. Information was collected on the patients' age, gender, smoking status, and occupation/job (blue collar versus white collar worker). They also looked at pain pattern (frequency, intensity, duration, recurrence), sick leave used, and previous history of surgery.

The patients also filled out a dozen self-report questionnaires on function, pain, depression, stress, fear-avoidance beliefs, catastrophizing, and coping. The authors analyzed the data and found five modifiable risk factors and five screening questions that could be used to predict patients at risk. Finding ways to rehabilitate those individuals and prevent long-term disability is the next step.

Worker characteristics that stood out as potential risk factors included: 1) high score on the Oswestry Disability Index (ODI) test, 2) high score on the fear-avoidance test, 3) blue-collar worker, 4) going on sick leave within 90 days of pain starting, and 5) pain behavior. The ODI is a means of assessing pain and the ability (or inability) to work or play in people with lumbar spine disorders. Fear-avoidance refers to changes in motion or the development of altered movement patterns that occur as a result of fear of reinjury or the belief that certain movements will cause pain.

Having patients fill out 12 questionnaires in order to identify who might be at risk of not returning to work is too time consuming and costly. That's why the researchers set out to find a quick and easy way to screen for return-to-work status. The five questions (taken from the 12 questionnaires) proposed that statistically showed a link with return-to-work behavior included:
  • Do you expect to work within six months?
  • How much does the pain interfere with your daily activities?
  • It is not advisable to be physically active (agree/disagree) -- answering agree increases the risk of non-return to work
  • Do you feel generally nervous?
  • Do you feel generally scared?

    Using these five questions, the authors report they were able to accurately identify two-thirds of the claimants in this study who did not return to work within 90 days after going on sick leave. Using a self-report method of assessment results in the patients making their own predictions about return-to-work. The presence of fear-avoidance beliefs as a risk factor leading to disability and deconditioning has been confirmed in other studies as well.

    The study was unique because there was no control group. Everyone was involved in the same compulsory insurance program. Another unique feature was the fact that the workers on sick benefits are legally required to complete this paperwork and follow all guidelines set by the physician.

    Workers included came from a wide range of different blue collar and white collar work settings. That means the results can be applied to workers in general and not just a particular subset of workers. However, the authors do point out that these findings may not apply to other types of insurance or claims compensation programs.

    The authors conclude by saying that it is possible to identify patients with low back pain who are at risk for delayed or long-term work absence. They plan to test this theory out now in a pilot study. The screening tool will be refined and validated before recommending its use on a routine basis.
    M. Du Bois, MD, et al. Patients at Risk for Long-Term Sick Leave Because of Low Back Pain. The Spine Journal. May 2009. Vol. 9. No. 5. Pp. 350-359.