Objective: This study aimed to determine if occupational exposure to whole-body vibration is associated with cervical intervertebral disc herniation among container truck drivers.
Methods: We conducted a walk-through survey among container truck drivers and unexposed workers. We also measured the vibration hazard of the container truck over the driver's back and seat when the driver was loading a container and driving the loaded truck.
Results and discussion: Among the 38 workers interviewed, 32 were container truck drivers. Four of them reported cervical herniated discs, and all of these individuals were container truck drivers with a job tenure of greater than 10 years. Self-reported cervical herniated disc, nuchal pain, nocturia, arm/forearm weakness, arm/forearm numbness, and finger numbness were significantly more prevalent as the driver's duration of exposure increased (all p values of test for trend <0.05). The vibration of the truck during and after loading a container was considered the main cause of herniated disc. When a container truck was driven with a loaded container, both the vertical and horizontal vibrating acceleration over the seat and back sites exceeded the 8-hr exposure level based on the ISO 2631-1 criteria. The transient vibration dose values (VDVs) measured during misaligned or unsmooth loading operations were usually greater than the upper bounds of the health guidance caution zone for the 8-hr VDV.
Conclusions: Our investigation disclosed a cluster of cervical intervertebral disc herniation that was associated with the vibration hazard during long-term container truck driving under full load and possibly aggravated by misaligned loading operations.