• Journal of Preventive Medicine and Public Health
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• v.14 no.1
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• pp.75-80
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• 1981

Due to rapid industrialization and economic development, the occupational diseases have appeared as one of the social problems in Korea. Up until now little has been known about the prevalence rate, predisposing factors and symptomatology of the occupational disease due to localized vibration in Korea. The researcher intends to investigate the prevalence rate and affecting factors of the occupational disease due to localized vibration among rock-drillers in the anthracite mines. A total of 135 rock-drillers were interviewed and examined from May 15th to 31th, 1980. The results were revealed as follows; 1. The prevalence rate of the vibration syndrome among rock-drillers was 12.6%. 2. The latent period of the vibration syndrome was 6.8 years. 3. The prevalence rate of the vibration syndrome was not significantly different between smokers and non-smokers. 4. With the increase of total vibration exposure time, the prevalence rate of the vibration syndrome increased also. 5. The average vibration sensation threshold was high (6.4dB) in stage 1 of the vibration syndrome and low (-0.6dB) in stage 0. 6. The average pain sensation threshold was high (4.4g) in stage 1 of the vibration syndrome and low (2.5g) in stage 0.

• International Journal of Clinical Preventive Dentistry
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• v.14 no.4
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• pp.235-240
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• 2018

Objective: The purpose of this study is to examine about dental hygienists' myofascial pain syndrome, lower back pain, carpal tunnel syndrome (CTS), medial and lateral epicondylitis, hand-arm vibration syndrom and work-related musculoskeletal syndrome (WMSD) experience and hygienists' posture, motion. Methods: The self-administered questionnaire was surveyed from June 1 to September 30 of 2018 targeting 280 dental hygienists in Gyeongnam province and 266 dental hygienists' answers were analyzed. Results: The average daily working hours of a dental hygienist was more than eight hours 59.0%, with an average of 33 patients per day. The average number of patients who receive treatment for more than 30 minutes is 15. The angle of motion of the subjective evaluation was above 60%. Medical position and form of movement were more than 50% above the standard level. Symptoms of posture and motion that cause WMSD were hand-arm vibration syndrome 68.1%, myofascial pain syndrome 58.6%, lower back pain 51.1%, CTS 50.4% in order. Experience WMSD related symptoms which dental hygienists experience were myofascial pain syndrome 92.9%, CTS 57.9%, lower back pain 56.4%, medial and lateral epicondylitis 37.2%, hand-arm vibration syndrome 24.4%. Conclusion: The above results showed the posture and motion of dental hygienists and were found that the experience rate which dental hygienists experience WMSD of myofascial pain syndrome, Lower back pain, and CTS was significantly more than 56%.

• Journal of Biosystems Engineering
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• v.27 no.4
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• pp.273-282
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• 2002

This study was intended to measure and analyze hand-transmitted vibrations from cultivator in idle and operation modes for three different types of field works. Based on this analysis a time for the white finger syndrome to appear on 10% of the operators was estimated assuming that their daily exposure is 3 hours. The 4 methods to reduce the hand vibration were also proposed and compared with each other. The results of the study were summarized as follows : The highest vibration level was recorded during trenching operation, resulting in a total average vibration of 11.5 m/s$^2$. Followings were 7.6 m/s$^2$ during rotary tillage and 7.0 m/s$^2$ for weeding. When exposed to these levels of vibrations three hours a day, the white finger syndrome is likely to appear in 4 years for trenching, 6.2 years for rotary tillage and 6.8 years for weeding operations. Isolation of hand vibration performed by a rubber pad, anti-vibration gloves, a handle anti-vibration device and engine mounts were respectively 15.7%, 16.5%. 26.1% and 27.0%, resulting in most effective methods of the handle anti-vibration device and engine mounts. A better performance of about 33.9% was achieved when both the handle anti-vibration device and engine mounts were used.

• Journal of the Ergonomics Society of Korea
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• v.32 no.4
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• pp.303-308
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• 2013

Objective: The aim of this study is to understand health effect of hand-arm transmitted vibration. Background: Electronic vibration tools have been used in many industries. These tools evoke hand-arm transmitted vibration that cause hand-arm vibration syndrome. Method: Various papers on the hand-arm transmitted vibration and its health effects have been reviewed to know what health effect caused. Results: Hand-arm transmitted vibration causes circulatory, neural, musculoskeletal and other disturbance. Conclusion: The previous studies focused on the epidemiology and physiology for hand-arm transmitted vibration. So, now we should focus on a prevention and guideline of hand-arm transmitted vibration. Application: These results can be used to know health effect of hand-arm transmitted vibration.

• Biomedical Science Letters
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• v.11 no.2
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• pp.193-199
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• 2005

The present study was performed to assess peripheral neural involvement by exposure to hand-arm vibration. Segmental sensory nerve conduction in the median and ulnar nerves were measured in shipyard workers exposed to vibration. The subjects were 47 male adults exposed to hand-arm vibration and 7 healthy male controls. The subjects underwent an extensive bilateral neurophysiological examination. Sensory compound nerve action potential (SNAP) of the median and ulnar nerves in palm-finger and wrist-palm segments were measured by antidromic method. And SNAP of the median and ulnar nerves in wrist-proximal finger and wrist-distal finger segments were measured by orthodromic method. Result of sensory nerve conduction study was abnormal in 31 patients $(66\%)$ and normal in 16 patients $(34\%)$ of subjects. The pathological pattern in the hand-arm vibration exposed group was 13 patients $(28\%)$ of carpal tunnel syndrome, 18 patients $(38\%)$ of distal sensory neuropathy, 7 patients $(15\%)$ of multifocal and 1 patient $(2\%)$ of Guyon syndrome. The present study indicates that vibration-induced nerve impairments exist both in the finger-palm and palm-wrist segment of median and ulnar sensory nerves. The results suggest that segmental sensory nerve conduction study would be useful as objective indication of peripheral nerve impairment induced by the hand-arm vibration.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.4
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• pp.398-412
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• 2006

The purpose of this study is to investigate the relationship between the acceleration of vibration by the powered hand tools used in the shipbuilding industry, and to develop the prospective prevalence model for the hand-arm vibration syndrome among the shipbuilding workers.The acceleration levels and frequencies of six types of grinder were measured using the ISO5349 method along with the time of exposure to the vibration from the powered hand tools. Medical examination for 114 workers were performed using the cold provocation test. Comparisons were made between the estimated prevalence of hand-arm vibration syndrome from ISO5349 and the observed values from the medical examinations. By multiple regression, we developed the prospective prevalence model of hand-arm vibration syndrome produced by the hand tools used in the shipbuilding industry. 4 hour-energy-equivalent frequency-weighted accelerations were $6.23m/s^2$ in the grinding job done after welding, and $13.39m/s^2$ in the grinding job done before painting. The mean exposure time while holding powered hand tools was 4.64 hours. Prevalence rates of Raynaud's Phenomenon were 12.04% in the grinding after soldering, and 42.9% in the grinding before painting measured using the ISO5349 method. After exposure to vibration for 10.79 years, about a half of the workers in the grinding after welding could developed Raynaud's Phenomenon. For the workers in the grinding before painting, the latency was 5.02 years. The ISO equation for dose response relationship was not significantly correlated with observed recovery rates of finger skin temperatures, blood flows and amplitudes of nerve conduction velocities. A multiple regression model for dose-response relationship was proposed from the results. Recovery rate of the skin temperatures = -0.668+ 0.337 ${\times}$ 4 hour energy equivalent frequency-weighted accelerations + 0.767 ${\times}$ duration of vibration exposure(years) The validity was proved by multiple regression analysis after correlation transformation and regression results based on model-building data and validation data.

• IE interfaces
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• v.17 no.3
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• pp.375-383
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• 2004

The purpose of this study is to investigate the characteristics of vibration induced by the powered hand tools used in the automobile assembly lines, and estimate the prevalence of vibration syndrome. The acceleration levels of four major powered hand tools were measured using the ISO 5349 method along with the time of exposure to the vibration of the hand tools. Four-hour-energy-equivalent frequency-weighted accelerations ranged from $1.27m/s^2$ to $2.58m/s^2$, After exposure to vibration for 12.6 years, about 10% of the workers using impact ranches were expected to develop Raynaud's disease. For the workers using grinders, 16.6% of the workers were expected to develop Raynaud's disease. The results would be of help in developing the guidelines of local vibration control.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.507-519
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• 1996

The objectives of this study are to investigate the prevalence of occupation related carpal tunnel syndrome(CTS) among workers in a condom industry : to analyse the sensitivity and specificity of clinical signs or symptoms such as hand diagram, Tinel's sign and Phalen's sign in carpal tunnel syndrome : and to test vibration threshold test using audiometry as a technically easy and noninvasive method in the diagnosis of carpal tunnel syndrome in stead of nerve conduction velocity (NCV). The study group was divided into exposed group(39 cases) and non-exposed group(48 cases) based on whether or not excessive use of wrist movements exsist. 1. There are stastically significant differences in symptoms and signs of carpal tunnel syndrome such as hand diagram, Tinel's sign and Phalen's sign between exposed and non-exposed group(p<0.05). 2. Six cases(9 hands) were comfirmed as carpal tunnel syndrome by NCV. Five cases(7 hands) belonged to exposed group, 1 case(2 hands) to nonexposed group. As there are significant differences in prevalence of carpal tunnel syndrome between two groups(p<0.05), excessive use of wrist in occupation is a risk factor of carpal tunnel syndrome. 3. When we use NCV as a gold standard in the diagnosis of carpal tunnel syndrome, sensitivity and specificity of hand diagram, Tinel's sign and Phalen's sign is as followed; hand diagram , sensitivity 88.9%, specificity 84.2% Tinel's sign ; sensitivity 55.6%, specificity 72.8% Phalen's sign ; sensitivity 14.3%, specificity 88.4%. Among above clinical signs and symptoms, hand diagram is the best clinical screening test. 4. The differences of vibration threshold between median and ulnar nerve at the same time are useful in the diagnosis of carpal tunnel syndrome but the time change of vibration threshold of median nerve over time are not sensitive enough. It is concluded that vibration threshold between median and ulnar nerve at the same time can be used as a supplementary or alternative criterion to indicate that the nerve dysfunction is located in the carpal tunnel.

• Journal of the Korean Society of Physical Medicine
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• v.16 no.1
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• pp.41-48
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• 2021

PURPOSE: The purpose of this study was to provide fundamental clinical data to be used in therapeutic approach to patients with patellofemoral pain syndrome by administrating the squat exercise combined with whole body vibration exercise to them and investigating the effect of such exercise to leg muscle activity and muscle fatigue. METHODS: The patients with patellofemoral pain syndrome were randomly assigned to experimental group I (n = 9) where only squat exercise was administered and experimental group II (n = 9) where the squat exercise combined with whole body vibration exercise was provided. The intervention program was administered for two weeks, four days a week, one session a day, three set a session, and 20 reps a set. The pre- and post-test were performed to measure muscle activity and muscle fatigue of vastus medialis and vastus lateralis. RESULTS: The muscle activity significantly changed in both group (p < .05, p < .01, respectively) and the muscle fatigue showed significant change only in group I (p < .05). In addition, there was significant difference between groups in change of muscle fatigue of both muscles (p < .05) but not in change of muscle activity. CONCLUSION: The results showed that both exercise are effective in improving muscle activity, however, that the squat exercise combined with whole body vibration exercise is more effective in preventing muscle fatigue.

• Journal of the Ergonomics Society of Korea
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• v.19 no.3
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• pp.93-107
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• 2000

The excessive exposure to powered hand tools can cause damage to nerves, impair blood circulation, and musculoskeletal damage. The symptoms associated with hand-arm vibration syndrome (HAVS) include numbness, tingling, pain and subsequent reduced dexterity of the hands. This study was performed to report the prevalence of the HAVS and evaluate its related factors among the workers using powered hand tools. Total 282 workers in 11 plants of Kyungki and Inchon areas were examined. A standard symptom questionnaire was developed and administered to collect information on personal characteristics, work history, operating conditions, tool characteristics, and subjective symptoms of HAVS. Mean values (standard deviations) of the age, the duration of powered hand tools used, and the daily hours using powered hand tools were 38.3(8.9) years, 79.3(62.2) months and 6.0(2.6) hours, respectively. 132 workers(46.8%) showed vibration-induced white finger symptoms according to the Taylor-Pelmear classification, and 30 workers(10.6%) were interfered with the work. The results of a multiple logistic regression analysis controlling for age and daily working hours showed that smoking, work duration, weight of tools, and continuous work over 2 hours were significantly associated with the symptom of HAVS.