Evidence & Methods
The small minority of patients with persisting low back pain who do not return to work represent a considerable burden to health care systems. Identifying those people at greatest risk for chronic LBP illness may direct preventive measures against long-term disability.
Based upon data collected from 12 standardized questionnaires the authors have shown that “blue collar work,”" abnormal pain behavior and a long back pain episode before disability were strong predictors of continued disability claims after 3 months. Elevated ODI and fear of avoidance severity scores had an apparently smaller effect. Subsequently, the authors distilled five questions that might, in the first week or two of work absence, be predictive of failure to return to work.
If the five questions prove predictive in further prospective study, they might be useful to identify patients at risk who would benefit from more focused intervention aimed at addressing their expectations, beliefs and affect.
Caution on two fronts is indicated. First, Information derived from this Belgian work population (and the social system in which they work) may not be readily transferable to a North American population. And second, the data presented also appears to indicate radicular pain may be an independent predictor, apart from psychosocial factors affecting outcome, which perhaps warrants a different assessment strategy.
—The Editors
The prognosis for most patients on sick leave to resume work is good [5]. Most of the treatment costs apply to the minority of patients (10%) who were not able to resume work after 3 months of sick leave. These claims account for 90% of all medical and indemnity costs attributable to LBP [6].
Studies of the natural history of non-specific LBP are potentially compromised by the health care received and are also affected by data collection methods, with higher quality studies including independent follow-up for at least 12 months [7], [8]. Recent systematic reviews of the clinical course of LBP indicate that rapid improvements occur in the first 3 months post-onset, but that improvements are gradual thereafter [9]. Croft et al. recommend revising the view of recent-onset LBP as being self-limiting with only a small proportion that becomes persistent (>12 weeks), to a model of LBP as an essentially persistent condition, characterized by frequent episodes of symptoms interspersed with periods of relative freedom from pain and activity limitation [10].
The etiology of non-specific low back disorders is considered multifactorial with a minor role for biomedical factors [11]. Prognostic factors for back pain disability have been elucidated by different reviews [12], [13], [14], [15]. Prolonged disability is not predicted simply by the severity of the injury, which is but one of a number of poorly understood determinants of chronic disability. The Boeing study has looked at a variety of factors which appear to predict delayed recovery [16]. The predictive factors tended to be psychosocial, rather than medical. New Zealand has developed a set of evidence-based acute back pain guidelines for health professionals advocating a move away from the medicalization of back pain. Complementary patient guides promote self-responsibility for episodes of back pain. One section of the guidelines emphasizes the importance of psychosocial risk factors in the disability associated with back pain [17].
Numerous studies on factors of back disability studied the relations between the factors causing LBP and sick leave attributed to LBP [18]. Fragmentary research and use of a limited set of risk factors in many studies complicate a holistic scientific approach to disability management. Additionally, inconsistency on outcome measurement, selection techniques and the structure of the compensation system complicates comparisons of reported predictors in sick leave studies [19]. The applicability of results of clinical studies to medical decision making in a specific social security or income replacement context might be limited.
Early return to useful and productive activity has been shown to decrease both disability and self-reported pain [20]. According to several guidelines, resuming normal activities and not pain relief is the primary goal in the rehabilitation of patients with chronic LBP [21], [22]. To achieve this goal, an interdisciplinary evaluation and an intensive active treatment are recommended [23]. The intensity of any treatment is strongly depending on the patient's conscious motivation to perform optimally during the evaluation and rehabilitation process [24].
There is a general agreement that patients with LBP should be encouraged and supported to remain at work or to undergo an early gradual return to work with modified duties [25], [26]. Rehabilitation management should therefore identify, as early as possible, those patients at high risk of persistent disabling symptoms [27], [28].
The holistic impact of known biopsychosocial factors at baseline on return to work needs to be studied in a standardized way. An investigation in a compulsory national health insurance setting is able to minimize confounding by compensation.
The purpose of this study was to determine the extent to which worker characteristics including worker's demographics, and clinical manifestation of LBP, work and workplace factors, and psychological features are useful in identifying claimants at higher risk of long-term incapacity versus those likely to return to work in a compulsory national health insurance setting. The second aim was to identify a limited set of screening questions for long-term sick leave in patients with LBP.
