2010 Volume 48 Issue 5 Pages 584-595
The aim of this study was to investigate the relation between low back pain (LBP) outcomes and measures of daily exposure to whole-body vibration (WBV) in professional drivers. In a study population of 202 male drivers, who were not affected with LBP at the initial survey, LBP in terms of duration, intensity, and disability was investigated over a two-year follow-up period. Vibration measurements were made on representative samples of machines and vehicles. The following measures of daily WBV exposure were obtained: (i) 8-h energy-equivalent frequency-weighted acceleration (highest axis), A(8)max in ms-2 r.m.s.; (ii) A(8)sum (root-sum-of-squares) in ms-2 r.m.s.; (iii) Vibration Dose Value (highest axis), VDVmax in ms-1.75; (iv) VDVsum (root-sum-of-quads) in ms-1.75. The cumulative incidence of LBP over the follow-up period was 38.6%. The incidence of high pain intensity and severe disability was 16.8 and 14.4%, respectively. After adjustment for several confounders, VDVmax or VDVsum gave better predictions of LBP outcomes over time than A(8)max or A(8)sum, respectively. Poor predictions were obtained with A(8)max, which is the currently preferred measure of daily WBV exposure in European countries. In multivariate data analysis, physical work load was a significant predictor of LBP outcomes over the follow-up period. Perceived psychosocial work environment was not associated with LBP.