To review and critically evaluate the past literature for spinal mechanical load as risk factor for low back pain (LBP).
LBP is a costly health problem worldwide, and treatments are often unsuccessful. Therefore, prevention might be more beneficial in the management of LBP. With respect to prevention, the knowledge of risk factors is essential. From the literature, exposures involving spinal mechanical load is frequently discussed as a potential risk factor for LBP. For a better understanding of this risk factor, we performed a systematic review of the literature. Additionally, we evaluated exposures of spinal mechanical load for possible dose-response relations with LBP.
We systematically searched Medline, Embase, PsycINFO, and CINAHL databases (without language restriction) for full-report publications of prospective cohort studies, evaluating spinal mechanical load during work and/or leisure time activities as risk factors for nonspecific LBP in patients (>18 years of age) free of LBP at baseline. We assessed the methodology of each article and extracted information on population, response rates, characteristics of LBP, exposures, and estimated association(s), using standardized forms. We performed a best evidence synthesis of the obtained information.
In total, 18 studies were eligible (all rated as high methodologic quality) reporting on 24,315 subjects.
We found strong evidence that leisure time sport or exercises, sitting, and prolonged standing/walking are not associated with LBP. Evidence for associations in leisure time activities (e.g., do-it-yourself home repair, gardening), whole-body vibration, nursing tasks, heavy physical work, and working with ones trunk in a bent and/or twisted position and LBP was conflicting. We found no studies, thus no evidence, for an association between sleeping or sporting on a professional level and LBP.
Systematically reviewing 18 prospective cohort studies yielded strong evidence for no-associations low back pain—leisure time sport (exercises), sitting, and standing/walking, and conflicting evidence for associations low back pain—leisure time activities, whole-body-vibration, nursing tasks, working with the trunk in a bent and/or twisted position, and heavy physical work.
From the *Department of General Practice, Erasmus University, Rotterdam, The Netherlands; and †Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Academic Medical Centre, Amsterdam, The Netherlands.
Acknowledgment date: August 28, 2008. Revision date: October 6, 2008. Acceptance date: October 6, 2008.
The manuscript submitted does not contain information about medical device(s)/drug(s).
No funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.
Address correspondence and reprint requests to Eric W. P. Bakker, PhD, Department of General Practice, Erasmus University Rotterdam, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands; E-mail: email@example.com