Whole-body vibration: is there a causal relationship to specific imaging findings of the spine?

Study Design: Systematic review.

Objective: To perform a systematic review of the available literature for those studies that evaluated the role of whole-body vibration (WBV) on the spine, using imaging modalities as well as an estimation of WBV exposure.

Summary Of Background Data: Numerous comparative studies have reported a possible association between the occurrence of spinal symptoms and exposure to WBV. These exposures have commonly been examined in the work environment largely through self-reported questionnaires only. From a scientific perspective, the majority of studies emphasize symptoms and lack objective medical evidence, such as spinal imaging, to help establish a specific spinal disorder. Because both neck and low back pain comprise symptoms that can arise from a host of factors including age, a casual link between spinal disorders and WBV cannot be affirmed.

Methods: MEDLINE and EMBASE were searched for studies related to WBV and spinal symptoms, diagnosis, and/or disorders. Our searches were limited to studies published prior to August 2011. The resulting 700 citations (after excluding 354 duplicates) were then screened by 3 independent reviewers on the basis of the following predetermined inclusion and exclusion criteria: inclusion-clinical studies with imaging evaluation (radiographs, computed tomographic scans, and/or magnetic resonance images) and documented WBV exposure (occupation, amount of WBV, and/or duration); exclusion-reliance solely on self-reporting of symptoms (neck pain, low back pain, and/or sciatica), those articles based on a clinical diagnosis without use of imaging, and in vitro/animal/biomechanical studies.

Results: Only 7 studies met the inclusion criteria for this systematic review. Included were 5 retrospective cohort and 2 cross-sectional studies. Although mixed results and conclusions were found, the majority of studies did not identify an association between WBV exposure and an abnormal spinal imaging finding indicating damage of the spine. We should also stress that each included study has limitations secondary to quantifying WBV exposure accurately, both as a single encounter and as a total exposure over years.

Conclusion: Based on our results from this systematic review, no causality can be shown between WBV and abnormal spinal imaging findings. With the conflicting data available in the literature, WBV has not been established as a cause for objective spinal pathological changes on a scientific basis.