Occurrence Of Vibration-induced White Finger Research Articles

Clinical effect and mechanism of acupuncture and moxibustion on occupational hand-arm vibration disease: A retrospective study

IntroductionThis is a retrospective study exploring clinical effect of acupuncture and moxibustion on upper limb disorder induced by occupational hand-arm vibration disease (OHAVD), and preliminarily exploring mechanism of the effect. Methods43 patients diagnosed with occupational HAVD were divided into experimental group (n = 21) and control group (n = 22). Before and after 4 weeks treatment, the occurrence of vibration-induced white finger(VWF) was observed, upper limb function was assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, based on which the DASH scores were determined, and the serum concentration of TNFα was detected using ELISA. ResultsPre-treatment DASH score was not significantly different between two groups, but post-treatment score was significantly lower in experimental group than in control group (21.94 ± 5.79vs.35.87 ± 3.80, p < 0.05).Post-treatment the occurrence of VWF in experimental group was significantly lower than that of pre-treatment (χ2 = 5.081, p = 0.024).88.37% of the pretreatment serum TNFα concentration was above reference range 8.1 pg/ml, and it was not significantly different between two groups. However, post-treatment TNFα concentration in experimental group was significantly lower than that in control group (10.51 ± 3.68 pg/ml vs.14.72 ± 8.66 pg/ml, p = 0.045). Further, the difference in DASH score and TNFα concentration before and after treatment was statistically significant between groups (p < 0.05). ConclusionsCombination of acupuncture and moxibustion may be an effective treatment for occupational HAVD, the mechanism is possibly related to reduction of the serum TNFα levels.

Risk assessment of vascular disorders by a supplementary hand-arm vascular weighting of hand-transmitted vibration.

To provide an updated epidemiological validation for a supplementary method for assessing the risk of vascular disorders from hand-transmitted vibration. The occurrence of vibration-induced white finger (VWF) in the vibration-exposed workers of the Italian cohort of the EU VIBRISKS study was related to measures of daily vibration exposure expressed in terms of r.m.s. acceleration magnitude normalised to an 8-h day, frequency weighted according to either the frequency weighting Wh defined in international standard ISO 5349-1:2001 [Ah(8) in ms- 2] or the hand-arm vascular frequency weighting Wp proposed in the ISO technical report (TR) 18570:2017 [Ap(8) in ms- 2]. To estimate a threshold value for vascular hand-arm vibration risk, the Wp-weighted vibration exposure value Ep,d (in ms- 1.5) was calculated according to the ISO/TR document. The difference in the predictions of VWF between the exposure measures calculated with the frequency weightings Wh or Wp was investigated by means of logistic modelling. Measures of daily vibration exposure constructed with the frequency weighting Wp [Ap(8) and Ep,d], which gives more importance to intermediate- and high-frequency vibration, were better predictors of the occurrence of VWF in the vibration-exposed workers than the metric derived from the conventional ISO frequency weighting Wh [Ah(8)]. There was some epidemiological evidence for a threshold value of Ep,d for the onset of VWF in the vibration-exposed workers. Measures of daily vibration exposure evaluated with the vascular weighting Wp performed better for the predictions of VWF than those obtained with the frequency weighting Wh recommended in ISO 5349-1.

A follow up study of vascular disorders in vibration-exposed forestry workers

To investigate the occurrence of vibration-induced white finger (VWF) and the cold response of digital arteries in a group of forestry workers, most of whom had used anti-vibration (AV) chain saws solely. One hundred and twenty-eight forestry workers underwent initially a medical examination and a standardized cold test with measurement of the change in finger systolic blood pressure after finger cooling from 30 to 10 degrees C (FSBP%(10 degrees )). They were re-examined two or three times over the calendar period 1990-1999. Seventy-one forestry workers were active over the entire follow up period, while 57 retired after 1-8 years from the initial investigation. The initial prevalence and the cumulative incidence of VWF over the follow up period were 26.6 and 11.7%, respectively. In the retired workers, the new cases of VWF occurred before their retirement, that is when they were still active. There were no significant changes in FSBP%(10 degrees ) in the active forestry workers over the follow up period. A significant increased in FSBP%(10 degrees ) (i.e. improvement) was observed in the retired workers at the end of the follow up. FSBP%(10 degrees ) at the cross-sectional investigation was significantly lower in the forestry workers who developed VWF during the follow up than in those who never experienced finger blanching over the study period. The findings of this follow up study suggest that forestry workers with work experience limited to AV chain saws are still at risk of developing VWF. Cessation of vibration exposure in the retired workers was associated with a beneficial effect on the cold response of digital arteries. Cold-induced digital arterial hyperresponsiveness at the initial investigation was a predictive factor for the onset of VWF over time.

Hand Arm Vibration Syndrome among Quarry Workers in Vietnam

Few studies have focused on the health effects of vibrating tools on workers in the tropical area. Work conditions and health effects related to rock drill operation were studied in 102 quarry workers, including 73 rock drill operators in Vietnam. We aimed to clarify (1) risk of vibration exposure, (2) occurrence of vibration-induced white finger (VWF), and (3) characteristics of hand-arm vibration syndrome (HAVS). Total weighted r.m.s. acceleration of the Chinese -or Russian-made rock drills, was 45-55 m/s(2). According to work observation studies, daily exposure time to vibration was 160-210 min. ISO5349 predicted that this exposure level would be associated with a high risk of HAVS in workers. We found no clear evidence of VWF. There may be several reasons why no worker exhibited VWF: (1) warmer work conditions, (2) younger and less experienced workers, (3) seasonal changes in work operations, and (4) healthy worker effect. On the other hand, 5-10% of rock drill operators might be suffering from moderate HAVS which was sensori-neural type dominant. There may be some characteristic features of HAVS among quarry workers in the tropical area.

Dose-response patterns for vibration-induced white finger

Aims: To investigate alternative relations between cumulative exposures to hand-transmitted vibration (taking account of vibration magnitude, lifetime exposure duration, and frequency of vibration) and the development of white finger (Raynaud’s...

A prospective study of the cold response of digital vessels in forestry workers exposed to saw vibration.

To investigate the occurrence of vibration-induced white finger (VWF) and the cold response of digital vessels in a group of 68 forestry workers who underwent a first clinical examination in 1990 and were then reexamined in 1995. The forestry workers were divided into three groups: group A (n = 27), active workers who did not have VWF in 1990 and continued to use chain saws; group B (n = 29), workers who did not have VWF in 1990 and retired before 1995; and group C (n = 12), active or retired workers who had VWF in 1990. The subjects underwent a medical interview, a complete physical examination, and a cold provocation test, which were performed by the same physicians at both surveys. The cold test consisted of measurement of the finger systolic blood pressure (FSBP) after local cooling to 10 degrees C, expressed as a percentage of the pressure recorded at 30 degrees C (FSBP%10 degrees). Three new cases of VWF occurred during the follow-up period among workers who had used only antivibration (AV) chain saws. The vasoconstrictor response to cold was unchanged in group A and improved in group B (P < 0.001). A significant decrease in VWF symptoms and abnormal response to cold was observed in group C (P < 0.05). As a result of preventive measures curtailing saw usage time in the VWF workers, the daily vibration exposure in group C was lower in 1995 than in 1990 (P = 0.02). In the retired workers, FSBP%10 degrees was positively related to the time since the cessation of work with chain saws (P < 0.01). The findings of this follow-up study indicate that a reduction in or cessation of exposure to vibration has a beneficial effect on finger-blanching symptoms and the cold response of digital vessels. The occurrence of new cases of VWF in subjects whose work experience was limited to AV chain saws argues for the maintenance of health surveillance in these workers.

Proposal for hand-arm vibration exposure limits adopted for Japanese workers operating hand-held vibration tools.

On the basis of data presented in our previous, reports, the current study was undertaken to estimate frequency-weighted hand-arm vibration exposure limits for various daily exposure times. The procedures for the present study were as follows. (1) The prevalence of vibration-induced white finger (VWF) as well as the vibration exposure were investigated in various groups of workers operating hand-held vibrating tools. The vibration magnitude of various tools was measured and the results were presented as the energy-equivalent frequency-weighted root-mean-square (m/s2 rms) acceleration. There was a statistically significant positive correlation between the prevalence of VWF and the measured vibration magnitude (R2 = 0.5, P < 0.05). Hence, it was concluded that in decisions concerning quantitative recommendations for vibration exposure, the prevalence of VWF should be considered. (2) By a careful selection of available publications which contain useful information on duration of vibration exposure of < or = 2 h/day and the occurrence of VWF, a significant correlation between the prevalence of VWF and the vibration magnitude could be observed. The regression equation was estimated as: y = -18.5 + 4.6 (x), R2 = 0.8. On the basis of this equation, it was speculated that the prevalence of VWF in workers using vibrating tools might be restricted to the prevalence of Raynaud's phenomenon in the Japanese general population if the 2-h daily vibration exposure is about 4.5 m/s2 rms. (3) Regarding this speculation, the equation provided in the documentation of ISO 5349 was used and modified as: [alpha h,w)eq,t = (alpha h,w)eq,2(2/t)1/2 (m/s2 rms)] and then the vibration limit values for daily exposure of 1 min to 8 h were calculated. (4) In order to achieve compatibility with standards of other countries, and to formulate an easy method for using the recommended values presented here, the daily exposure time of 8, 4, 2, 1 and 0.5 h were selected. The correspondence vibration magnitudes were in the range 22-9.0 m/s2 rms, and the lower limit (2.2 m/s2 rms) was assumed as the permissible vibration exposure limit for an 8-h working period. The proposed daily vibration limits were then compared with those recommended by other institutions.

Vibration Exposure, Vibration-Induced White Finger and Digital Arterial Tone in Chain Saw Operators

In a group of 65 Italian forestry operators using chain saws, the overall prevalence of vibration-induced white finger (VWF) was found to be 29.2%. The occurrence of VWF was higher in the chain sawyers who had operated non-antivibration (non-A/V) as well as A/V saws (46.4%) than in those with experience limited to A/V saws (16.2%). The latency time before VWF averaged 9.4 yr (SD 6.8). The mean value of the four-hour energy-equivalent frequency-weighted acceleration [(ah,w)eq(4)] was 7.2 m/s2 (SD 1.2). On the basis of the known VWF prevalence and of [(ah,w)eq(4)], a latent period before VWF of 7.1 yr was expected according to ISO 5349. The measurement of finger systolic pressure (FSP) at 15°C and 10°C by plethysmographic technique showed that the chain sawyers affected with VWF experienced a more intense digital vasospasm than a group of comparable controls and the chain sawyers without VWF. The sensitivity of the method to detect vibration-induced digital arterial hyper-responsiveness to cold was 84.2% and the specificity was 100%. The findings of this study showed a good agreement between the expected and observed latency times before VWF, even though the ISO dose-effect relationship seems to overestimate slightly the risk. The results of the cold test indicated that the measurement of FSP during local cooling is an accurate laboratory method to diagnose objectively Raynaud's phenomenon of occupational origin.