Virokannas H, Virokannas A
Department of Public Health Science and General Practice, University of Oulu, Finland.
Cent Eur J Public Health. 1995;3 Suppl:66-9.
Exposure to hand-arm vibration causes damage in the peripheral nerves of the upper extremities, and a method for early detection of neuropathy induced by vibration is needed. The thin nerve fibres seem to be the most sensitive to vibration and may be damaged first. In the present study, vibration and thermal thresholds in workers exposed to hand-arm vibration were compared in a case-control study. Previously, both vibration perception and temperature sense have been impaired in workers exposed to hand-arm vibration. The study population consisted of 15 workers exposed to hand-arm vibration (mean age 37.1 yrs) and 15 controls matched for age (mean age 36.1 yrs). The vibration perception thresholds (VPT) were measured with modified Bruel & Kjaer's equipment with the limits technique method. Thermal sense was measured by the Marstock method with a thermostimulator, in which the Peltier element controls the temperature of a thin metal plate (surface 35 x 40 mm) in contact with the skin. The lumberjacks had lower cold thresholds and wider neutral zones of temperature sensation in the hands and slightly higher VPTs at the high frequencies (125-500 Hz) than the controls. The results for the matched pairs showed 80-87% of the lumberjacks to have wider neutral zones, but only 53-66% of them had higher VPTs than the controls. In an intraindividual comparison of the lumberjacks (the newly scaled results with the mean and standard deviation of the controls), the temperature sense was often (66-73%) deteriorated more than the VPTs at 125-500 Hz. In addition, the newly scaled results showed the width of the neutral zone to be significantly more deteriorated than the VPTs at 125 and 250 Hz in the fingers. This indicates that measurement of the temperature sense is useful in the prevention of nerve damage caused by vibration and might be more sensitive to vibration than vibration perception.
接触手臂振动会导致上肢周围神经损伤，因此需要一种早期检测振动诱发神经病变的方法。细神经纤维似乎对振动最为敏感，可能最先受损。在本病例对照研究中，对接触手臂振动的工人的振动和热阈值进行了比较。此前，接触手臂振动的工人的振动觉和温度觉均已受损。研究人群包括15名接触手臂振动的工人（平均年龄37.1岁）和15名年龄匹配的对照组（平均年龄36.1岁）。采用改良的Bruel & Kjaer设备，运用极限技术方法测量振动觉阈值（VPT）。采用Marstock方法，使用热刺激器测量温度觉，其中珀耳帖元件控制与皮肤接触的薄金属板（表面35×40毫米）的温度。与对照组相比，伐木工的手部冷阈值较低，温度感觉的中性区较宽，在高频（125 - 500赫兹）时VPT略高。配对结果显示，80 - 87%的伐木工中性区较宽，但只有53 - 66%的伐木工VPT高于对照组。在伐木工的个体内比较（新标度结果与对照组的均值和标准差）中，温度觉经常（66 - 73%）比125 - 500赫兹时的VPT恶化更严重。此外，新标度结果显示，手指处125和250赫兹时中性区的宽度比VPT恶化更显著。这表明温度觉测量在预防振动引起的神经损伤方面有用，并且可能比振动觉对振动更敏感。
