Key Strike Forces and Their Relation to High Level of Musculoskeletal Symptoms

BACKGROUND: This study aimed to investigate the relation between key strike forces and musculoskeletal symptoms (MSS). Moreover, this study presents a key strike force measurement method to be used in a workplace setting. The correlation between key strike force characteristics and MSS was previously studied, but the measurement methods used either a single-key switch or force platforms applied under the keyboard. Most of the studies were conducted in a laboratory setting. The uniqueness of measurement methods in the current study is their ability to measure forces applied to a specific key in a workplace setting and to provide more information about specific key strike forces during typing. METHODS: Twenty-four healthy computer workers were recruited for the study. The demographic questionnaire, and self-reported questionnaires for psychosocial status (General Nordic Questionnaire for Psychological and Social Factors at Work) and for detecting MSS were filled up, which later helped in dividing the participants into two groups (12 participants with pain and 12 without pain). Participants typed a predetermined text that utilized the instrumented keys multiple times. The dynamic forces applied to the keys were recorded and collected, using four thin and flexible force sensors attached to the preselected keys according to their location. RESULTS: The results demonstrated that participants with high levels of MSS, specifically in the back and neck, in the last year exerted significantly higher key strike forces than those with lower levels of symptoms (p < 0.005). CONCLUSION: The key strike force exerted while typing on a keyboard may be a risk factor for MSS, and should therefore be considered in ergonomic evaluations and interventional programs.

Job Stress and Musculoskeletal Disorder in Seoul City's School Foodservice Employees / 한국직업건강간호학회지

PURPOSE: School foodservice employees (SFEs) could be exposed to the risk of musculoskeletal disease and of job stress due to their job characteristics. This study was to evaluate the level of job stress and the prevalence of work-related musculoskeletal symptoms (WRMS) in Seoul city's SFEs, and to determine associations between job stress and WRMS. METHODS: The study design was cross-sectional, and 975 SFEs were recruited. Self-administered questionnaire included the 'Korean occupational stress scale-short form' and the 'KOSHA GUIDE H-9-2012' instrument to evaluate the job stress and WRMS, respectively. SFEs' medians of job stress were compared to the reference values of published study in Korean workers. RESULTS: The participants reported greater levels of job demand and physical environment than the general Korean population. WRMS were reported in 89.0% of participants at any body part, and 41.1% were presumed to need for medical intervention. High levels of job demand and of physical environment were significantly associated with WRMS. CONCLUSION: Subscales of job demand and physical environment were relatively high in SFEs and those were related to the occurrence of WRMS. To reduce the WRMS prevalence, a job stress management program focused on job demand and physical environment may be required.

Job Stress and Musculoskeletal Disorder in Seoul City's School Foodservice Employees / 산업간호학회지

PURPOSE: School foodservice employees (SFEs) could be exposed to the risk of musculoskeletal disease and of job stress due to their job characteristics. This study was to evaluate the level of job stress and the prevalence of work-related musculoskeletal symptoms (WRMS) in Seoul city's SFEs, and to determine associations between job stress and WRMS. METHODS: The study design was cross-sectional, and 975 SFEs were recruited. Self-administered questionnaire included the 'Korean occupational stress scale-short form' and the 'KOSHA GUIDE H-9-2012' instrument to evaluate the job stress and WRMS, respectively. SFEs' medians of job stress were compared to the reference values of published study in Korean workers. RESULTS: The participants reported greater levels of job demand and physical environment than the general Korean population. WRMS were reported in 89.0% of participants at any body part, and 41.1% were presumed to need for medical intervention. High levels of job demand and of physical environment were significantly associated with WRMS. CONCLUSION: Subscales of job demand and physical environment were relatively high in SFEs and those were related to the occurrence of WRMS. To reduce the WRMS prevalence, a job stress management program focused on job demand and physical environment may be required.

Current Status of Sickness Absences and Early Leaves from Work among Workers with Work-related Musculoskeletal Symptoms in Each Body Part, and Relevant Factors / 대한산업의학회지

OBJECTIVES: The purpose of this study was to identify current status of sickness absence and early leaves from work as a result of work-related musculoskeletal symptoms. METHOD: From January to December in 2007, 4,975 workers were recruited into this study and surveyed over this time period; workers came from 116 small and medium sized companies in Incheon. Among the study populations, only those who met the NIOSH criteria for work-related musculoskeletal symptoms on each symptom locations were included in the final analysis. The survey used a structured self-administered questionnaire, which asked questions about musculoskeletal symptoms regarding locations, sickness absences and early leaves from work. Other information gathered from participants included sociodemographical characteristics, and work-related characteristics. RESULTS: The rates of sickness absences and early leaves in each symptom locations were highest (14.9%) among workers with waist symptoms. Men had higher rates of sickness absences and early leaves form work than women; manufacturing workers had higher rates of sickness absences and early leaves form work than office workers. After confounding variables that had significant difference in univariate analysis on each symptom locations were adjusted, the odds ratios for sickness absence and early leaves divided by pain intensity were 4.361(neck), 4.140(shoulder), 3.151(arm/wrist), 3.085(leg/foot), and 2.731(waist), respectively; these differences were statistically significant. CONCLUSIONS: The rates of sickness absence and early leaves in each work-related musculoskeletal symptom locations were highest among workers with waist symptoms, and the intensity of pain was identified to have a considerable effect on the rates of sickness absences and early leaves. Based on these results, we think that there are needs to be early interventions on workers with waist symptoms.

Work-Related Musculoskeletal Symptoms Among Dairy Farmers in Gyeonggi Province, Korea / 예방의학회지

OBJECTIVES: The prevalence of work-related musculoskeletal symptoms (WMS) among Korean dairy farmers has not been investigated. The purpose of this study was to assess the prevalence of WMS and to evaluate the relationship between WMS and risk factors. METHODS: Self-developed questionnaires including the questionnaire developed by the Korean Occupational Safety and Health agency (KOSHA) were used to investigate WMS among dairy farmers in Gyeonggi Province, Korea. We informed selected dairy farmers about the study and sent the questionnaires by registered mail. They visited a public health center nearby or a branch of public health center on the appointed date and skillful researchers identified or conducted the questionnaires by interview. We analyzed 598 (32.8%) of the 1824 dairy farmers. Multiple logistic regression was implemented to estimate the odds ratios of risk factors. RESULTS: The mean age of the respondents was 50.4 +/- 8.7 years and the proportion of males was 63.0%. The prevalence of WMS at any site was 33.3%. The prevalence of neck WMS was 2.2%, shoulders 10.0%, arms/elbows 5.0%, hands/wrists/fingers 4.2%, low back 11.5%, and legs/feet 11.7%. The adjusted odds ratio of low back WMS for milking 4 or more hours per day was 4.231 (95% CI = 1.124 - 15.932) and statistically significant. Low back WMS (2.827, 95% CI = 1.545 - 5.174) was significantly decreased by education. CONCLUSIONS: Low back WMS increased with milking hours and milking 4 or more hours per day was significantly associated with low back WMS. Low back WMS was significantly reduced with education. We hope that there will be increased attention about WMS in dairy farmers and the subject of future investigations.

Work Related Musculoskeletal Disorders of Hairdresser / 대한산업의학회지

OBJECTIVES: To determine the prevalence and related factors of work related musculoskeletal symptoms in hairdressers. METHODS: Informations on general characteristics, job strain, and musculoskeletal symptoms were obtained by a self-administered questionnaire, through adopting NIOSH instrument and JCQ(Job content questionnaire), from 267 hairdressers, between March and May, 2000. RESULTS: The symptom prevalence by NIOSH surveillance criteria in total was high as 94.4%; shoulder (61.0%), neck (59.9%), low back (53.2%), hand and wrist (41.6%), etc. In multiple logistic regression, significant factors affecting the symptoms by body region; job insecurity on neck' gender, alcohol, decision latitude on low back; alcohol on hand and wrist; smoking on thigh and knee,' smoking, decision latitude on ankle and foot; job insecurity on upper back. CONCLUSIONS: Musculoskeletal symptoms of hairdresser were highly prevalent, and associated with job strain and their health habits. This is a basic data of work related musculoskeletal disorders among hairdressers who are not the subjects of occupational health service at the present time in Korea.