Advances on nervous system impairment induced by hand-transmitted vibration / 环境与职业医学

Hand-transmitted vibration is one of the most common physical harmful factors in the workplace，and the hand-arm vibration syndrome caused by it lacks effective treatment, and seriously affects the physical and mental health of the involved workers. As an important target for hand-transmitted vibration, the nervous system has attracted increasing attention from scholars, and much progress has been made in recent years in studying the effects of hand-transmitted vibration on nervous system function. Based on related literature at home and abroad, this paper introduced the hand-transmitted vibration-associated damage in peripheral, autonomic, and central nervous systems, and then explored the associated influence factors, like vibration frequency, environment temperature, and individual factors. The potential directions for further research were also proposed.

Hand-transmitted vibration and occupational health / 环境与职业医学

The hand-arm vibration disease due to widespread hand-transmitted vibration operations is difficult to cure and seriously affects the health and quality of life of patients. Focusing on the prevention and control of hand-transmitted vibration and its occupational hazards, advances in occupational health relevant to hand-transmitted vibration were reviewed from the aspects of occupational hazard status, health impact, exposure monitoring, prevention and control of hand-transmitted vibration, as well as health surveillance, diagnosis, and treatment of hand-arm vibration disease. In addition, further suggestions on prevention and control of occupational hazards related with hand-transmitted vibration were prospected.

Application of cold intolerance symptom severity questionnaire among vibration-exposed workers as a screening tool for the early detection of hand-arm vibration syndrome: a cross-sectional study

BACKGROUND: The detection rate of hand-arm vibration syndrome (HAVS) is very low in South Korea compared with other countries. The absence of uniform consensus and guidelines for diagnosing HAVS has been presumed to be one of the reasons. The HAVS has various manifestations including cold intolerance and its severity can be measured using the cold intolerance symptom severity (CISS) questionnaire. This study aimed to determine whether the CISS questionnaire, being used as a screening tool, can aid in the early detection of HAVS. METHODS: A total of 76 male workers with vibration-induced symptoms were enrolled as the final study participants. To compare the CISS score of healthy individuals, 41 men who had never been exposed to local vibration were included in the study. In addition to the former medical questionnaire, the participants answered the CISS questionnaire. A statistical analysis was conducted to identify the association of CISS scores with vibration induced symptom and to determine its cut off value. RESULTS: The reliability of the CISS questionnaire was proven to be good, with a total Cronbach's alpha of 0.922. The mean CISS score of the exposed group increased in every vascular stage [stage 0 = 42.6 (18.5); stage 1 = 59.4 (14.1); and over stage 2 = 60.2 (21.6)]. They were significantly higher than that of the non-exposed group. The result was fairly consistent with those in the sensorineural stage. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under curve (AUC) of 30 were 88.5, 65.3, 76.1, 82.1 and 0.769, respectively. From the result of logistic regression, the adjusted odds ratio of both components increased by the CISS score grouped by 30s. CONCLUSIONS: The self-reported CISS questionnaire, used to measure the degree of cold intolerance, showed high agreement with the Stockholm classification of HAVS. Hence, we recommend the use of this questionnaire to assess the level of cold intolerance among vibration-exposed workers and detect individuals who are at risk of vibration-induced impairment with a cutoff value of 30. TRIAL REGISTRATION: IRB No. 2018–07–040-001. Registered on 4 September 2018.

Síndrome vibratorio mano-brazo: revisión literaria / Hand-arm vibratory syndrome: literary review

Resumen El síndrome vibratorio mano-brazo forma parte de la categoría de enfermedades ocupacionales o asociadas al trabajo, específicamente aquellos trabajos manuales en los que se utilicen herramientas vibratorias, como taladros, moledoras, martillos neumáticos, sierras y cualquier otra que transmita energía vibratoria directamente a la mano y brazo del trabajador. La descripción de los primeros casos de este síndrome tuvo lugar hace ya más de un siglo, y con el desarrollo industrial se volvió progresivamente, en una entidad más importante en cuanto a la discapacidad y la pérdida de calidad de vida que genera en los pacientes, así como las pérdidas económicas y de horas laborales que produce a nivel mundial, en especial en los países más desarrollados en donde su prevalencia es notablemente mayor. En el presente artículo se ha realizado una revisión literaria acerca de los principales signos y síntomas de esta enfermedad, su clasificación, fisiopatología y métodos de diagnóstico. También se abordarán los mecanismos de prevención así como el pronóstico y evolución de los pacientes una vez han sido diagnosticados.

Abstract Hand-arm vibration syndrome is part of the occupational or work-related illness category, specifically those manual workers using vibratory tools such as drills, grinders, pneumatic hammers, saws and any other tool that transmits vibratory energy directly to the Hand and arm of the worker. The description of the first cases of this syndrome took place more than a century ago, and with the industrial development it became progressively, in a more important entity as far as the disability and the loss of quality of life that generates in the patients, As well as the economic losses and hours of work that it produces worldwide, especially in the more developed countries where its prevalence is significantly higher. In this article a literary review has been carried out on the main signs and symptoms of this disease, its classification, pathophysiology and diagnostic methods. The mechanisms of prevention as well as the prognosis and evolution of the patients once they have been diagnosed will also be addressed.

Essential characteristics of hand-arm vibration in hand-held workpiece polishing / 中国职业医学

OBJECTIVE: To study the occupational exposure characteristics of hand-transmitted vibration in hand-held workpiece polishing and to provide the basis for occupational hazard prevention and control technology research in this kind of job. METHODS: The questionnaire and on site occupational health investigation were used to study 4 typical enterprises of hand-held workpiece polishing. The study was conducted by filling forms by enterprise,personal interviews with administrative staffs and front-line workers,as well as on site visit. RESULTS: Among the 4 factories,there were 835workers( 22. 4%) engaged in the hand-held workpiece polishing assignment. The principal vibrating tools used in these 4factories were polishing machine,flint glazing machine and polishing wheel,and the workpiece polished by workers were button,toilet lid,thermos,mobile phone shell and golf head. The polishing workers were all equipped with noise reduction earplugs and anti-dust respirators, but they did not wear anti-vibration gloves. The hand-held workpiece polishing assignment has the characteristics including indirect and continuous vibration exposure and fine operation. Some workers used their knees and abdomens as the support to polish workpieces. The vibration exposure time was 6-11 h / d. The 4hours energy equivalent frequency-weighted acceleration to vibration [ahw( 4)]was 1. 9-19. 4 m/s~2,with the maximum which exceeded the occupational exposure limit( 5. 0 m / s~2),showing a wide range ahw( 4)in the same enterprise. CONCLUSION: Compared with the traditional vibrating tools,the hand-held workpiece polishing operation has different characteristics of hand-transmitted vibration such as more sophisticated machine structure,finer polishing ways,more influencing factors of vibration exposure level and more extensive body parts involved.

The prevalence of hand arm vibration syndrome among automobile assembly workers

The objectives of this study are to determine the prevalence of hand-arm vibration (HAVS) among the automobile assembly workers and the associated risks. A cross sectional study was conducted to determine the prevalence of HAVS and also ascertain the association between HAVS and reduction in VPT among workers using vibration hand held tool in automobile industry. Aim of this study was to determine the prevalence Hand Arm Vibration Syndrome (HAVS) among vibrating hand held tool exposed workers. A cross sectional study design using structured questionnaire and invasive measurement of vibrotactile perception threshold (VPT) at the fingertips was conducted in one of the automobile company in Klang Valley. All the respondents were hand arm vibration exposed workers. A total 109 assembly line workers with at least one year job tenure participated in this study. The finding revealed that 27.5% of workers reported HAVS through questionnaire. This study consisted of 109 respondents. All of them were male. The mean age was 32.9 years. The mean daily vibration exposure for 8-hours was 1.41m/s2. There was 11% of the tools measured were above the Action Level recommended by European Union Directive 2002. The overall prevalence of HAVS based on reported symptom through questionnaire was 27.5%. None of the respondent reported any whiteness at their fingers due to exposure to vibration. However, 36.7% of the respondent reported tingling sensation and 57.8 % reported the feeling of numbness in their hands. Only 10.1% claim that the pain was persistence. Since this study was done among exposed workers without control group, the thresholds were measured by comparing the observed VPT with the VPT of healthy population provided by ISO 13091-2. The result showed that 98.2% of the respondent in this study having positive threshold which indicate the percentage of respondent that having deterioration in finger tactile perception. The positive threshold from comparison above showed that the respondent of this study was affected with the vibration exposure. The value proven that the exposure has caused the deterioration of tactile sensitivity in 98.2% of respondent in this study which showed by having positive threshold compared to healthy population. The result also showed that there was a significant correlation between daily vibration exposure A (8) and VPT at both frequency tested which was 31.5Hz (r = 0.417, p = 0.002) and 125Hz (r = 0.480, p = 0.001). Even though the mean daily vibration exposure for 8-hours was low and below the recommended level, the workers still exposed to the effect of hand arm vibration

Nailfold capillary microscopy for evaluating hand-arm vibration syndrome

OBJECTIVES: We evaluated nailfold capillary abnormalities in patients with hand-arm vibration syndrome using nailfold capillary microscopy. METHODS: Fifty workers who underwent a special health examination because of exposure to hand-arm vibration at Ulsan University Hospital in 2012 (exposed group) and a control group of 50 white-collar employees were evaluated through a questionnaire survey regarding their present tasks, types of tools used, vibration exposure duration, use of protective wear, and medical history. Then, an occupational physician performed a physical examination for any hand deformities, skin problems, or motor and sensory dysfunctions of the upper extremities. The nailfold capillary morphologies (tortuous, crossing, bushy, meandering, branching, hemorrhage, avascular area, enlarged, and giant), capillary dimensions (afferent, top, venous, total width, and length), and specific counts (crossing and branching) on both fourth fingers were determined by a rheumatologist. Thereafter, the exposed subjects were assessed according to the Stockholm workshop classification scale. In total, 8 and 6 subjects in the exposed and control groups, respectively, were excluded from the study because of poor capillary microscopic image quality. In addition, 24 subjects in the exposed group with Stockholm vascular stage 0 were excluded. Finally, capillary morphology, dimensions, and specific counting were compared between the exposed (n = 18) and control groups (n = 44). RESULTS: The exposed group had significantly greater crossing capillaries and abnormal capillary numbers that included crossing capillaries (crossing, branching, bushy, and meandering) but smaller branching and abnormal capillary numbers that excluded crossing capillaries (branching, bushy, and meandering) than the control group did. No significant difference in capillary dimensions was observed between the two groups. Despite the adjustment for age, smoking status, and underlying diseases, the statistical significance was unchanged. In the specific counting of the type of capillaries, the exposed group had a significantly higher total crossing count but fewer total branching count than the control group did. However, no statistical significance resulted after adjustment for age, smoking status, and underlying diseases. CONCLUSIONS: In this study, the exposed group had significantly more crossing capillaries and a higher crossing count than the control group did.

The General Characteristics and Results of the Cold Provocation Test in the Risk Group of HAVS / 대한산업의학회지

OBJECTIVES: The cold provocation test for diagnosing the vascular component in hand-arm vibration syndrome (HAVS) is likely to be accepted as an objective test, and a few studies have been performed. However, controversy has continued regarding the diagnostic performance of this method. Although objective methods such as plethysmography and laser doppler flowmetry have been studied, they have not received as much attention as other diagnostic methods. Therefore, our study aim was to spread the awareness of HAVS by reporting the results of the cold provocation test in a hand-transmitted vibration exposure group. METHODS: The study subjects were 549 workers who had been exposed to hand-transmitted vibrations and reported symptoms in their hands. While the subject immersed both their hands in 10degrees C water for 10 minutes, the skin temperature of 10 fingers was recorded from pre-immersion time to 20 minute postimmersion including 10 minutes immersion time. The recovery rates were calculated from the recorded skin temperatures. The 'decreased recovery rate' criteria were less than 30% at 5 minutes post-immersion and 60% at 10 minute post-immersion. RESULTS: Of the subjects, 69.1% and 30.9% had more severe symptoms in the right and left hands, respectively. The mean finger skin temperature of the right hand after cold-water immersion for 10 minutes was approximately 10degrees C, which increased gradually with time, but they did not reach the baseline temperature at 20 minutes post-immersion. The deviations of the skin temperature in the subjects were higher in the recovery phase than in the baseline and cold immersion phase. The 3rd finger of both hands showed the lowest 5-minute recovery rate among the fingers examined, and the left 4th finger and right 3rd finger showed the lowest 10-minute recovery rate. Of the subjects, 37.6% and 10.4% of subjects showed a lower recovery rate at 5 and 10 minutes in at least one finger, respectively, while 10.2% showed a lower recovery rate at both 5 and 10 minutes simultaneously in at least one finger. CONCLUSIONS: The larger deviations in the recovery phase than in the other phases indicated that interindividual differences are more prominent in the recovery phase. There might be no benefit in observing the finger skin temperature for an additional 10 minutes after 10 minutes post-immersion. Overall, approximately 10% of the subjects in the HAVS risk group had HAVS.

Effect of Hand Transmitted Vibration on the Auditory System / 대한산업의학회지

OBJECTIVES: This study was undertaken to estimate the effect of hand transmitted vibration exposure for long time period on the auditory system in shipyard grinder workers. METHODS: From 2006 to 2009, the study was carried out on 87 grinder workers for hand transmitted vibration exposure group, with 81 welders who were served as the control group. All subjects were male; at baseline, none of the participants had ear disease or diabetes mellitus. Auditory threshold at different frequencies ranged from 0.25 kHz to 8 kHz for both ear was recorded; the following were also collected from the subjects: age, exposure duration, noise exposure level of investigation year, total cholesterol, systolic/diastolic blood pressure, and smoking history. RESULTS: In comparison of two groups, mean of age, exposure duration, noise level, total cholesterol, systolic/diastolic blood pressure, smoking rate were not significantly different between the groups. Auditory thresholds of 0.25, 0.5 kHz frequencies in both ear, 1 kHz frequency in right ear, and 8 kHz frequency in left ear were higher in hand-transmitted vibration exposure group than that in the control group at a statistically significant level. After stratification by age 50 years, there were no significant differences between the two groups in less than 50-years old age group, but auditory threshold of 0.25, 0.5, 1 and 8 kHz frequency were significantly different between the two groups in above 50-years old age group. The differences between two groups ranged from 0.4 dB(HL) to 6.7 dB(HL). Multiple linear regression analysis showed that hand transmitted vibration exposure was significant only in 0.25, 0.5 kHz frequency and the regression coefficients of vibration exposure ranged from 3.826 to 5.028 in those frequencies. CONCLUSIONS: The differences of hearing threshold between two groups only in the 50-years old group were possibly owing to changed peripheral vascular system with autonomic nervous system, and significances only in low frequencies such as 0.25, 0.5 kHz probably mean that hand vibration exposure have been transmitted to auditory organ over long term. Collectively, older people can be more susceptible to hearing loss in the presence of hand transmitted vibration exposure and auditory threshold at low frequency may be more affected by the hand transmitted vibration exposure than high frequency.

Early Objectified Detection Method of Sensorineural Component in Hand Arm Vibration Syndrome / 대한산업의학회지

OBJECTIVES: In order to determine find out the best methods for a more objective detection of neurologic abnormality in early hand arm vibration syndrome(HAVS), early with analyzing the validity of each of the detection methods was analyzed. We evaluated the relationships between the sensorineural stage of Stockholm-revised vibration syndrome classification and the results of several tests. METHODS: 497 workers were investigated for symptom, exposure duration, the types of tools used, and medical history from January 2000 to December 2007. Pain sense threshold, vibrotactile threshold, hand grasp force, finger grasp force, and a finger tapping frequency test were performed by the workers. RESULTS: The grinder(67.3%) was the most commonly used tool and the mean exposure duration was 14.8 years. Although the pain sense and vibrotactile threshold level tended to increase according to sensorineural stage of the Stockholm classification, there was statistically significant difference in the vibrotactile threshold of 125, 250 Hz (p=0.006~0.038) but not in the pain sense threshold. Hand and finger grasp force tended to decrease according to the sensorineural stage of Stockholm classification and there was statistically significant difference(p=0.041,<0.001, 0.034) only on the right hand side. The tapping frequency also generally decreased according to the sensorineural stage of the Stockholm classification and there was statistically significant difference (p=0.002~0.019) only on the left hand side. CONCLUSIONS: Although there is no single standardized method that can objectively diagnose the sensorineural component of early HAVS early, the combination of subjective symptoms, the sensorineural stage of Stockholm classification, the pain and vibrotactile threshold test, the hand and finger grasp force, and the finger agility (tapping) test can objectively detect sensorineural component of HAVS early.

Early Objectified Detection Method of Sensorineural Component in Hand Arm Vibration Syndrome / 대한산업의학회지

OBJECTIVES: In order to determine find out the best methods for a more objective detection of neurologic abnormality in early hand arm vibration syndrome(HAVS), early with analyzing the validity of each of the detection methods was analyzed. We evaluated the relationships between the sensorineural stage of Stockholm-revised vibration syndrome classification and the results of several tests. METHODS: 497 workers were investigated for symptom, exposure duration, the types of tools used, and medical history from January 2000 to December 2007. Pain sense threshold, vibrotactile threshold, hand grasp force, finger grasp force, and a finger tapping frequency test were performed by the workers. RESULTS: The grinder(67.3%) was the most commonly used tool and the mean exposure duration was 14.8 years. Although the pain sense and vibrotactile threshold level tended to increase according to sensorineural stage of the Stockholm classification, there was statistically significant difference in the vibrotactile threshold of 125, 250 Hz (p=0.006~0.038) but not in the pain sense threshold. Hand and finger grasp force tended to decrease according to the sensorineural stage of Stockholm classification and there was statistically significant difference(p=0.041,<0.001, 0.034) only on the right hand side. The tapping frequency also generally decreased according to the sensorineural stage of the Stockholm classification and there was statistically significant difference (p=0.002~0.019) only on the left hand side. CONCLUSIONS: Although there is no single standardized method that can objectively diagnose the sensorineural component of early HAVS early, the combination of subjective symptoms, the sensorineural stage of Stockholm classification, the pain and vibrotactile threshold test, the hand and finger grasp force, and the finger agility (tapping) test can objectively detect sensorineural component of HAVS early.

Significance of finger coldness in hand-arm vibration syndrome

<p><b>OBJECTIVES</b>To evaluate the relationship between subjective symptoms of coldness in fingers and peripheral circulation in patients with hand-arm vibration syndrome (HAVS).</p><p><b>METHODS</b>Thirty-five male patients confirmed to have HAVS as an occupational disease took part in this study. Their mean age was 62 years (SD 5) and all were chain-saw operators exposed to vibration for an average of 25 years. Their annual health examination included the history of their daily habits (smoking, drinking, and therapeutic exercise), report of subjective symptoms such as coldness, numbness and tingling in the fingers, and a physical examination; laboratory tests consisted of skin temperature measurement, and pain and vibration perception under conditions of cold provocation. A frequently used method of cold provocation, immersion of the left hand up to the wrist in water of 10°C for 10 min, was used.</p><p><b>RESULTS</b>Finger coldness was classified into 3 groups according to its severity: mild group (n=8), moderate group (n=17) and severe group (n=10). There was no significant difference in age or occupational background between the groups. A significant association was found between finger coldness and prevalence of Raynaud's pheno menon (p<001, χ(2)). The mean skin temperature was significantly lower with the severity of finger coldness (ANOVA, p<0.05). In the cold provocation test, there was no significant difference between skin temperature and coldness at 5 min and 10 min after immersion, though a difference was observed immediately after immersion. No significant difference was observed in the relationship between finger coldness and vibrotactile threshold before, during or after the cold provocation test.</p><p><b>CONCLUSIONS</b>The severity of coldness in the fingers is significantly related to skin temperature. The severity of finger coldness reflects the extent of peripheral circulatory vasoconstriction. Coldness in the fingers may be a good warning of potential problems in peripheral, circulatory function.</p>

Significance of Finger Coldness in Hand-Arm Vibration Syndrome

Objectives: To evaluate the relationship between subjective symptoms of coldness in fingers and peripheral circulation in patients with hand-arm vibration syndrome (HAVS). Methods: Thirty-five male patients confirmed to have HAVS as an occupational disease took part in this study. Their mean age was 62 years (SD 5) and all were chain-saw operators exposed to vibration for an average of 25 years. Their annual health examination included the history of their daily habits (smoking, drinking, and therapeutic exercise), report of subjective symptoms such as coldness, numbness and tingling in the fingers, and a physical examination; laboratory tests consisted of skin temperature measurement, and pain and vibration perception under conditions of cold provocation. A frequently used method of cold provocation, immersion of the left hand up to the wrist in water of 10°C for 10 min, was used. Results: Finger coldness was classified into 3 groups according to its severity: mild group (n=8), moderate group (n=17) and severe group (n=10). There was no significant difference in age or occupational background between the groups. A significant association was found between finger coldness and prevalence of Raynaud's phenomenon (p<001, χ2-test). The mean skin temperature was significantly lower with the severity of finger coldness (ANOVA, p<0.05). In the cold provocation test, there was no significant difference between skin temperature and coldness at 5 min and 10 min after immersion, though a difference was observed immediately after immersion. No significant difference was observed in the relationship between finger coldness and vibrotactile threshold before, during or after the cold provocation test. Conclusions: The severity of coldness in the fingers is significantly related to skin temperature. The severity of finger coldness reflects the extent of peripheral circulatory vasoconstriction. Coldness in the fingers may be a good warning of potential problems in peripheral circulatory function.

Different Conditions of Cold Water Immersion Test for Diagnosing Hand-Arm Vibration Syndrome

The cold water immersion test with finger skin temperature (FST) measurement is used to assess vascular disorders in hand-arm vibration syndrome (HAVS). The test method is currently being standardized within the International Organization for Standardization (ISO) in which a water temperature of 12°C for 5 min of hand immersion and an option of using a waterproof hand covering during immersion are proposed. It is necessary to evaluate the diagnostic significance of the test with FST measurement under different conditions to provide a proper management of HAVS patients. The aim of this article is to review research findings of this test with FST measurement and discuss test conditions influencing the results and diagnostic significance. Different conditions were employed, and the test results were shown to be influenced by water temperature, immersion time and other conditions such as room temperature, season, ischemia during immersion, and evaluation parameters. These factors need to be considered in the standardization of the cold water immersion test with FST measurement. It has been mentioned that a high water temperature, a short immersion time and other conditions should be chosen to expose a subject to minimal suffering during the test. A water temperature between 10°C and 15°C and a 5 min immersion might be suitable for the cold water immersion test. The reported sensitivity and specificity evaluating rewarming to the initial temperature for the test using a water temperature of 12°C and a 3 min immersion are 58% and 100%, respectively; these are low but similar to those for the water immersion test at 10°C. Therefore, the proposed cold water immersion test at 12°C for 5 min by the ISO (Draft International Standard) is the focus of much interest, and further studies are needed to obtain sufficient data for evaluating the diagnostic significance of the test. At present, the test needs to be used together with a test battery.

Epidemiologic Characteristics of Hand-Arm Vibration Syndrome through Occupational Disease Surveillance System in Busan, Ulsan, Kyungnam Province / 대한산업의학회지

OBJECTIVES: The objectives of this study were to estimate the epidemiologic characteristics of hand-arm vibration syndrome (HAVS) due to occupational exposure of hand transmitted vibration and to identify the occupations and industries where such exposures arises, and the main sources of exposure. METHODS: In April 2001 the Busan, Ulsan, and Kyung-Nam Province occupational disease surveillance system was established to measure the incidence and prevalence of work-related HAVS and other occupational diseases in these Korean provinces. Occupational physicians of nine hospitals in Busan, Ulsan, and Kyung-nam Province were involved in this project between April 2001 and November 2002. Physicians collected information through questionnaires and interviews. Information gathered included age, occupation, types of vibration tools used and presence of subjective symptoms such as vibration-induced white finger (VWF), numbness and tingling. RESULTS: A total 192 cases were reported with 188 males and 4 females. The shipbuilding industry was the most common type of industry and grinders were the most common source of exposure. Symptoms of neurological disorder were more common than those of vascular disorder. CONCLUSIONS: The authors concluded that exposure to hand transmitted vibration is common and that HAVS is one of the most common occupational diseases in Korea. However, the range and extent of hand transmitted vibration and the overall prevalence of HAVS in Korea is still unknown. More extensive research on this syndrome in order to priorite necessary preventive measures is required.

Evaluation of Health Exams on Local Vibration Illness among Shipyard Workers / 대한산업의학회지

A hand-arm vibration syndrome, local vibration illness, occurs in some workers who use hand held vibration tools. It consists of white fingers, diffusely distributed finger neuropathy, pain in the hand and arm, and a small excess risk of osteoarthritis. This study is aimed to identify effective methods to confirm local vibration illness among various health exams, which are mentioned in worker's special health exam regulation. In addition, this study is aimed to quantitatively assess the daily vibration exposure level as a major determinant of vibration illness. The subjects, 46 vibration workers, were selected according to the results of the first special health exam about vibration hazards at shipbuilding industry in 1997. They all had experiences of work related blanching of fingers. Fifteen controls, who had no vibration exposure at all, were also recruited to compare their test results with the results of vibration workers. We adopted 1 subjective and 6 objective tests to evaluate the effectiveness and feasibility for confirming local vibration illness. These tests were history taking of subjective symptoms according to the Stockholm classification, checking blood pressure of finger, checking grasp power, checking finger skin temperature, nail-bed pressing test, vibration perceptional threshold test, and skin prick test for pain perception. Among these, checking skin temperature, nail-bed pressing test, and vibration perception test included cold water provocations. We also estimated some vibration exposure levels of hand held vibration tools by using previously published data from one automobile company. In conclusion, history taking of subjective symptoms according to the Stockholm classification, nail-bed pressing test, and vibration perceptional threshold test were discovered to be effective to diagnose local vibration illness. Furthermore, vibration perceptional threshold on right fingers showed a dose-response relationship to daily vibration exposure levels. The parameter beta was 0.0005(+/-0.0002), and statistically significant by REM (random effects model).

Quantitative Sensory and Vascular Tests in the Assessment of Hand-Arm Vibration Syndrome / 대한산업의학회지

This study was conducted on 103 male workers exposed to local vibration (exposure workers) and 23 male clergical workers not exposed to local vibration (reference workers) to evaluate the effect of local vibration in a automobile industry workers who had used vibratory tools such as electric bolt impacter or grinder. The assessment methods of this study were some tests recommended by Wasserman and Taylor. None of reference workers complained sensorineural symptoms, but 43.7% of exposed workers complained over one of those symptoms. The proportion of non-recovery type, which means that there was no full recovery of temperature of finger tips, was from 0% to 31. 3% in reference workers and from 10.7% to 15.5% in exposure workers. There was statistically significant difference of recovery time of plethysmogram after cold provocation between mean recovery time of 0.44 minutes in reference workers and that of 3.05 minutes in exposure workers. The proportion of bad plethysmogram was from 0% to 4.4% in reference workers and from 3.9% to 7.8% in exposure workers. There was statistically significant difference of discrimination sense between mean length of 2.04 mm in reference workers and that of 2.9 mm in exposure workers. There were also statistically significant difference of pain sense between mean weights of from 5.02 g to 5.26 g in reference workers and those of from 6.81 g to 7.6 g in exposure workers. By the results of multiple stepwise regression analysis the statistically significant variable affecting discrimination and pain sense was exposure and those affecting vibration sense were exposure and age. We concluded that exposure of local vibration in automobile workers was significaritly associated with decrease of sensorineural sense regardless of age and other, possible related variables.

Quantitative Sensory and Vascular Tests in the Assessment of Hand-Arm Vibration Syndrome / 대한산업의학회지

This study was conducted on 103 male workers exposed to local vibration (exposure workers) and 23 male clergical workers not exposed to local vibration (reference workers) to evaluate the effect of local vibration in a automobile industry workers who had used vibratory tools such as electric bolt impacter or grinder. The assessment methods of this study were some tests recommended by Wasserman and Taylor. None of reference workers complained sensorineural symptoms, but 43.7% of exposed workers complained over one of those symptoms. The proportion of non-recovery type, which means that there was no full recovery of temperature of finger tips, was from 0% to 31. 3% in reference workers and from 10.7% to 15.5% in exposure workers. There was statistically significant difference of recovery time of plethysmogram after cold provocation between mean recovery time of 0.44 minutes in reference workers and that of 3.05 minutes in exposure workers. The proportion of bad plethysmogram was from 0% to 4.4% in reference workers and from 3.9% to 7.8% in exposure workers. There was statistically significant difference of discrimination sense between mean length of 2.04 mm in reference workers and that of 2.9 mm in exposure workers. There were also statistically significant difference of pain sense between mean weights of from 5.02 g to 5.26 g in reference workers and those of from 6.81 g to 7.6 g in exposure workers. By the results of multiple stepwise regression analysis the statistically significant variable affecting discrimination and pain sense was exposure and those affecting vibration sense were exposure and age. We concluded that exposure of local vibration in automobile workers was significaritly associated with decrease of sensorineural sense regardless of age and other, possible related variables.

Combined Effect of Vibration Intensity, Grip Temperature, Noise and Pushing Power on Grip Forces and Skin Temperatures of Fingers / 예방의학회지

Recent studies reveal that grip forces during the hand-arm vibration are most significant for the genesis of vibration-induced white finger syndrome. Therefore, exerted grip forces and skin temperatures or fingers were regarded as dependent variables in experiments and the effects of grip temperature, noise, pushing force, vibration and the combined effect of vibration and pushing force were studied. The objectives or the present study were, first, to varify and compare the changes of grip force affected by grip temperature, noise, pushing force, vibration and the combined effect of vibration and pushing force and, second, to observe the reaction of finger skin temperature affected by above factors. Forty-six healthy male students(25.07+/-2.85) participated in five systematically permuted trials, which endured 4 minutes each other. Experiments were executed in a special chamber with an air temperature of 21 C. In each experiments, the subjects were exposed to five experiment types: (l) grip force of 25 N only, (2) pushing force of 50 N, (3) acceleration of vibration 7.1m/sec2(z-direction), (4) pink noise or 95 dB(A) and (5) combination of pushing force 50 N and acceleration of vibration 7.1m/sec2. A repeated-measures analysis of variance(ANOVA) was performed on the grip force to test whether it was affected by noise, pushing force, vibration and pushing force. The present results show that vibration was significantly related to the increase of grip force, but the other factors, such as pushing force, noise and grip temperature had no significant influence on the increase of grip force and that the reaction of finger skin temperature were significantly affected by the skin temperature at start of experiment and grip temperature, not grip force and other experimental conditions. Therefore, we suggest that the management for decreasing the grip force is meaningful to prevent the occurrence of Hand-arm vibration syndrome (HAVS).