Abstract
Pathophysiology of Vibration-Induced White Finger and Safety Levels for HandTransmitted Vibration: Ryoichi INABA, et al. Department of Hygiene, Gifu University School of Medicine-This review addresses the pathogenic mechanism and vibration safety values of vibrationinduced white finger (VWF). Sympathetic hyperactivity alone has long been postulated to account for VWF, but damage to vasoregulatory structures and functions in the finger skin now also seems to be involved. The physiological complexity of the response to cold is so great and the interaction between various vasoregulatory mechanisms so intricate that only a multifactorial etiology and pathogenesis is likely for VWF. These factors will be discussed in detail. Regarding vibration safety values, the prevalence of VWF and vibration magnitude (hand-transmitted vibration levels (HTVLs)) in various groups of workers which reported in our previous studies were reviewed. The prevalence rates of VWF were compared to the prevalence rates of Raynaud''s phenomenon (RP) in a large group of males and females without vibration exposure. It was observed that in subjects exposed to HTVLs of between 1.1 and 2.5 m/s2, the prevalence of VWF was 0.0-4.8%. The prevalence of VWF in workers exposed to HTVLs of up to 5.1 m/s2 was 9.6% and significantly higher than the prevalence of RP in males in the general population (2.7%). A significant positive correlation between VWF and HTVLs values was obtained. By employing the results obtained on vibration magnitude and the prevalence of VWF, estimated vibration safety levels are discussed. (J Occup Health 1996; 38: 1-5)
