Table 1.
Relationship of driving and whole body vibration to magnetic resonance imaging (MRI)-diagnosed disc herniation and/or nerve root compression or displacement. Separate models were constructed for each vibration variable. [OR=odds ratio; 95% CI=95% confidence interval; rms=root mean square.]
| Vibration exposure |
Controls (N=820) |
Cases with disc herniation and/or nerve root compression/displacement on MRI (N=176) |
Cases without disc herniation and/or nerve root compression/displacement on MRI (N=61) |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| N | % | N | % | OR | 95% CI a | OR | 95% CI b | N | % | OR | 95% CI a | OR | 95% CI b | |
| Professional driving (≥1 hours/day) |
||||||||||||||
| No | 677 | 82.6 | 147 | 83.5 | 1 | · · | 1 | · · | 50 | 82.0 | 1 | · · | 1 | · · |
| Yes | 143 | 17.4 | 29 | 16.5 | 0.8 | 0.5–1.3 | 0.8 | 0.5–1.3 | 11 | 18.0 | 1.1 | 0.5–2.2 | 1.1 | 0.5–2.2 |
| Professional driving (≥3 hours/time) |
||||||||||||||
| No | 765 | 93.3 | 163 | 92.6 | 1 | · · | 1 | · · | 56 | 91.8 | 1 | · · | 1 | · · |
| Yes | 55 | 6.7 | 13 | 7.4 | 1.0 | 0.5–1.8 | 0.9 | 0.5–1.8 | 5 | 8.2 | 1.3 | 0.5–3.5 | 1.4 | 0.5–4.1 |
| Average hours driven/week for commonest source |
||||||||||||||
| None | 677 | 82.6 | 147 | 83.5 | 1 | · · | 1 | · · | 50 | 82.0 | 1 | · · | 1 | · · |
| <16 | 67 | 8.2 | 19 | 10.8 | 1.2 | 0.7–2.0 | 1.2 | 0.7–2.2 | 5 | 8.2 | 1.0 | 0.4–2.7 | 1.1 | 0.4–3.1 |
| ≥16 | 76 | 9.3 | 10 | 5.7 | 0.5 | 0.2–1.0 | 0.5 | 0.2–1.0 | 6 | 9.8 | 1.1 | 0.4–2.9 | 1.0 | 0.4–2.7 |
| Total hours driven/week, all sources |
||||||||||||||
| Not a regular driver |
677 | 82.6 | 147 | 83.5 | 1 | · · | 1 | · · | 50 | 82.0 | 1 | · · | 1 | · · |
| <15 | 54 | 6.6 | 17 | 9.7 | 1.3 | 0.7–2.3 | 1.4 | 0.7–2.5 | 5 | 8.2 | 1.3 | 0.5–3.3 | 1.4 | 0.5–3.9 |
| ≥15 | 89 | 10.9 | 12 | 6.8 | 0.5 | 0.3–1.0 | 0.5 | 0.2–1.0 | 6 | 9.8 | 1.0 | 0.4–2.4 | 0.8 | 0.3–2.2 |
| Max rms of any machine (ms−2) |
||||||||||||||
| Not a regular driver |
677 | 82.6 | 147 | 83.5 | 1 | · · | 1 | · · | 50 | 82.0 | 1 | · · | 1 | · · |
| 0.5 | 87 | 10.6 | 21 | 11.9 | 1.0 | 0.6–1.7 | 1.0 | 0.6–1.7 | 6 | 9.8 | 1.0 | 0.4–2.4 | 1.0 | 0.4–2.5 |
| ≥0.6 | 56 | 6.8 | 8 | 4.6 | 0.5 | 0.2–1.2 | 0.5 | 0.2–1.2 | 5 | 8.2 | 1.3 | 0.5–3.5 | 1.1 | 0.4–3.3 |
| Current rms A(8) (ms−2) |
||||||||||||||
| <0.5 | 697 | 85.0 | 149 | 84.7 | 1 | · · | 1 | · · | 52 | 85.3 | 1 | · · | 1 | · · |
| ≥0.5 | 123 | 15.0 | 27 | 15.3 | 0.9 | 0.5–1.4 | 0.9 | 0.5–1.5 | 9 | 14.8 | 1.0 | 0.5–2.2 | 0.9 | 0.4–2.2 |
Adjusted for age (in 3 bands) and sex.
Adjusted for age (in 3 bands), sex, BMI (in 3 bands), somatising tendency (in 3 bands), SF-36 mental health score (in 3 bands), smoking status (current, ex, never smoker), propensity to consult over back pain (in three bands), fear avoidance beliefs (in three bands), belief in work as a cause of back pain (in three bands), occupational digging and/or lifting (in two bands) and occupational bending and/or twisting (in two bands).