Whole-body vibration and low back pain: a systematic, critical review of the epidemiological literature 1992-1999

Objectives: A previous extensive review of the literature including that from the middle of 1992 concluded that whole-body vibrations may contribute to low back pain, but that the exposure-response relationship had not been clarified. We reviewed the literature of the past 7 years to find out: (i) whether there is evidence in the recent epidemiological literature for a causal association between whole-body vibrations and low back pain, and (ii) if there is evidence in the recent literature for a dose-response relationship between whole-body vibrations and low back pain. Methods: All relevant epidemiological articles which were obtained through a search in the databases MEDLINE, OSH-ROM and TOXLINE, and through personal communication, were reviewed independently by the two authors, using a checklist. Results: Twenty-four original articles concerning the association between whole-body vibrations and the lower back were retained for use. The quality of the papers was mostly low, but improved with time. Only seven articles passed our predetermined quality criteria. Of the seven reports, one showed increased frequency of lumbar prolapse in occupational drivers, and six showed low back pain to be more frequent in whole-body vibration-exposed groups. Only two out of the four articles reporting on dose, showed a dose-response association. Conclusions: Despite the lack of definite evidence, we found sufficient reasons for the reduction of whole-body vibration-exposure to the lowest possible level. If new knowledge is to be produced, good prospective studies with repeated measurements of exposure, analyses of work postures, and clear definitions and subgroupings of low back pain are needed. Other research in this field should be given up, and the resources used for more important issues, as the size of the problem of whole body vibration is probably on the decrease because of the technical prophylactic developments that are already in progress.