Okada Akira, Nakamura Hiroyuki
Kanazawa University, Japan.
Sangyo Eiseigaku Zasshi. 2013;55(2):62-8. doi: 10.1539/sangyoeisei.a12002. Epub 2013 Jan 11.
Whole-body vibration (WBV) with high level acceleration is found in the workplaces of construction and mining, and has been reported to be associated with low back pain (LBP) experienced by operators of heavy vehicles as an occupational health problem. Because the work conditions with exposure to WBV include bending and twisting of the low back and other factors, the causal relationship between WBV and LBP has not yet been affirmed. A review suggesting the dose-response relationship between WBV with low acceleration and LBP has been published, although there is little evidence supporting the causal relationship. Therefore, we reviewed the dose-response relationship between WBV with low acceleration and LBP.
We examined original articles which reported a dose-response relationship between WBV and LBP in addition to review articles with almost the same aims.
Studies which examined imaging findings such as CT and MRI, objective indicators of LBP, do not confirm the causal relationship. Although many studies demonstrated a positive relationship between working periods and incidence of LBP, there were very few reports which recognized a dose-response relationship for the vibration acceleration below 1.0 m/s(2) in which the 8-h energy-equivalent, combined frequency-weighted vibration of three diagonal, that is x, y and z, axes (root-sum-of-squares), Asum(8) was used as an index of vibration exposure.
This paper reject the hypothesis of a dose-response relationship between WBV with low acceleration and LBP, concluding there is no evidence linking low level exposure to WBV with LBP for the Japan Society for Occupational Health to recommend 0.35 m/s(2)/as of Asum(8) as a tentative occupational exposure limits for WBV.
在建筑和采矿工作场所发现存在高水平加速度的全身振动（WBV），并且据报道，重型车辆操作员所经历的腰痛（LBP）作为职业健康问题与WBV有关。由于接触WBV的工作条件包括腰部的弯曲和扭转以及其他因素，WBV与LBP之间的因果关系尚未得到证实。尽管几乎没有证据支持因果关系，但已有一篇综述表明低加速度WBV与LBP之间存在剂量反应关系。因此，我们对低加速度WBV与LBP之间的剂量反应关系进行了综述。
我们除了查阅具有几乎相同目的的综述文章外，还研究了报告WBV与LBP之间剂量反应关系的原始文章。
检查诸如CT和MRI等影像学结果（LBP的客观指标）的研究未证实因果关系。尽管许多研究表明工作时长与LBP发病率之间存在正相关关系，但很少有报告认可振动加速度低于1.0 m/s²时的剂量反应关系，其中使用三个对角线轴（即x、y和z轴）的8小时能量等效、组合频率加权振动（均方根）Asum(8)作为振动暴露指标。
本文拒绝低加速度WBV与LBP之间存在剂量反应关系的假设，得出结论，没有证据表明日本职业健康学会将0.35 m/s²（Asum(8)）作为WBV的暂定职业接触限值与低水平WBV暴露和LBP之间存在关联。
