POSSIBLE MECHANISMS OF LOW-BACK-PAIN DUE TO WHOLE-BODY VIBRATION

The investigators describe their multifaceted approach to the study of the relationship between whole-body vibration and low back pain. In v ivo experiments, using percutaneous pin-mounted accelerometers have sh own that the natural frequency is at 4.5 Hz. The frequency response wa s affected by posture, seating, and seat-back inclination. The respons e appears to be largely determined by the rocking of the pelvis. Elect romyographic studies have shown that muscle fatigue occurs under whole body vibration. After whole body vibration exposure the muscle respon se to a sudden load has greater latency. Vehicle driving may be a reas on for low back pain or herniated nucleus pulposus. Prolonged seating exposure, coupled with the whole body vibration should be reduced for those recovering from these problems. Vibration attenuating seats, and correct ergonomic layout of the cabs may reduce the risks of recurren ce. (C) 1998 Academic Press.