Table 5
Low back and neck–shoulder pain (VAS) in urban bus drivers before and after driving (low back support vs. no support)
Baseline After driving Low back pain (0–100 mm)
Healthy (n = 15)
No support 4.5 ± 4.0 8.3 ± 8.8
Support 2.4 ± 1.4 5.1 ± 4.3*
Low back trouble (n = 25)
No support 19.6 ± 26.6 23.8 ± 25.2
Support 21.5 ± 23.9 22.0 ± 22.2
Pooled (n = 40)
No support 14.0 ± 22.3 18.0 ± 21.8*
Support 14.4 ± 21.0 15.7 ± 19.5
Neck–shoulder pain (0–100 mm) Healthy (n = 15)
No support 10.5 ± 14.8 12.3 ± 11.9
Support 8.3 ± 12.8 7.9 ± 7.2
Low back trouble (n = 25)
No support 18.5 ± 21.8 20.8 ± 24.7
Table 6
Low back and neck–shoulder fatigue (VAS) in urban bus drivers before and after driving (low back support vs. no support)
Baseline After driving Low back fatigue (0–100 mm)
Healthy (n = 15)
No support 5.4 ± 3.9 13.3 ± 13.2*
Support 3.9 ± 2.8 10.3 ± 12.3
Low back trouble (n = 25)
No support 16.2 ± 19.5 29.2 ± 24.5‡
Support 15.5 ± 16.5 32.1 ± 24.4‡
Pooled (n = 40)
No support 12.2 ± 16.3 23.2 ± 22.2‡
Support 11.2 ± 14.2 23.9 ± 23.1‡
Neck–shoulder fatigue (0–100 mm) Healthy (n = 15)
No support 5.5 ± 4.4 16.4 ± 13.6†
Support 8.6 ± 11.9 11.7 ± 13.4*
Low back trouble (n = 25)
No support 18.2 ± 23.6 25.5 ± 20.5*
Support 15.4 ± 15.9 28.4 ± 20.7‡
Pooled (n = 40)
No support 13.4 ± 19.7 22.1 ± 18.6‡
Support 12.9 ± 14.7 22.1 ± 19.9‡
Values are expressed as mean ± S.D.
* P < 0.05.
† P < 0.01.
‡ P < 0.001.
Table 7
Vibration pain provocation test, pain increased when vibrated in urban bus drivers
Healthy (n = 14) Back disorder (n = 24)
Painfull 0 12
Painless 14 12
Vibration pain provocation was positive in 12 and negative in 12 drivers with recurrent LBP and also negative in all back healthy drivers (Table 7). Vibration pain provocation test reproduced exact or similar pain as their back pain for seven subjects and dissimilar pain for 17 subjects (Table 8).
The positive pain provocation indicated significantly increase of LBP (P = 0.029), neck–shoulder pain (P = 0.007), low back (P = 0.001) and neck–shoulder (P < 0.001) fatigue by driving (Table 9).
The earliest signs of lumbar disc degeneration was found in all 15 subjects (pain provocation positive in nine cases) examined by MRI. The signs of annular rupture were seen in nine subjects, protrusion in eight, small disc herniation in two subjects and one spinal stenosis. The annular rupture was
Table 8
Pain sensation in urban bus drivers when compressing and/or vibrating by vibrator
Support 16.4 ± 25.2 21.2 ± 20.9
Pooled (n = 40)
No support 15.5 ± 19.7 17.6 ± 21.1
Support 13.4 ± 21.6 16.2 ± 18.2
Values are expressed as mean ± S.D.
* P < 0.05.