The effect of workplace intervention on pain and sickness absence caused by upper-extremity musculoskeletal disorders.

OBJECTIVES: The aim of this study was to assess the effect of an ergonomic intervention on pain and sickness absence caused by upper-extremity musculoskeletal disorders. METHODS: In this randomized controlled study, subjects aged 18-60 years (N=177) seeking medical advice due to upper-extremity symptoms were included if their symptoms, or the exacerbation of symptoms, had started <30 days prior to the medical consultation and immediate sick leave was not required. Workplace ergonomic improvements were made in the intervention group. Data on symptoms and sickness absences were gathered during one-year follow-up. RESULTS: Pain intensity, pain interference with work, leisure time, or sleep did not differ between the intervention and control group during the one-year follow-up. During the first three months of follow-up, the percentage of employees with sickness absence due to upper-extremity or other musculoskeletal disorders did not differ between the intervention (N=89) and control (N=84) group, but the total number of sickness absence days in the intervention group was about half of that in the control group (mean 6.2 versus 9.8 days for upper-extremity disorder and 6.0 versus 11.5 days for upper-extremity and other musculoskeletal disorders combined). During 4-12 months of follow-up, the percentage of employees with sickness absence due to upper-extremity disorder (10.1% versus 16.7%, P=0.20) or upper-extremity and other musculoskeletal disorders combined (20.2% versus 32.1%, P=0.07) was lower in the intervention than the control group. CONCLUSIONS: Our findings suggest that an early ergonomic intervention reduces sickness absence due to upper-extremity or other musculoskeletal disorders.

Computer-associated health complaints and sources of ergonomic instructions in computer-related issues among Finnish adolescents: a cross-sectional study.

BACKGROUND: The use of computers has increased among adolescents, as have musculoskeletal symptoms. There is evidence that these symptoms can be reduced through an ergonomics approach and through education. The purpose of this study was to examine where adolescents had received ergonomic instructions related to computer use, and whether receiving these instructions was associated with a reduced prevalence of computer-associated health complaints. METHODS: Mailed survey with nationally representative sample of 12 to 18-year-old Finns in 2001 (n = 7292, response rate 70%). In total, 6961 youths reported using a computer. We tested the associations of computer use time and received ergonomic instructions (predictor variables) with computer-associated health complaints (outcome variables) using logistic regression analysis. RESULTS: To prevent computer-associated complaints, 61.2% reported having been instructed to arrange their desk/chair/screen in the right position, 71.5% to take rest breaks. The older age group (16-18 years) reported receiving instructions or being self-instructed more often than the 12- to 14-year-olds (p < 0.001). Among both age groups the sources of instructions included school (33.1%), family (28.6%), self (self-instructed) (12.5%), ICT-related (8.6%), friends (1.5%) and health professionals (0.8%). Receiving instructions was not related to lower prevalence of computer-associated health complaints. CONCLUSIONS: This report shows that ergonomic instructions on how to prevent computer-related musculoskeletal problems fail to reach a substantial number of children. Furthermore, the reported sources of instructions vary greatly in terms of reliability.

Effectiveness of an ergonomic intervention on the productivity of workers with upper-extremity disorders--a randomized controlled trial.

OBJECTIVES: The aim of this study was to investigate the effectiveness of an ergonomic intervention on productivity loss at work caused by upper-extremity disorders (UED). METHODS: Workers with medically verified UED were invited to participate. The intervention consisted of a physician contacting the worker's supervisor and an occupational physiotherapist conducting an ergonomic assessment at the worksite. Before and after the intervention, the employees self-assessed UED-related productivity loss (ie, decreased quality and quantity of the daily work output). We tested for differences between groups at 8 and sub-sequently 12 weeks. We also applied generalized estimating equation (GEE) to analyze repeated measures data. RESULTS: Altogether 177 employees were randomized. The overall participation rate was 88%. At baseline, 54% of the intervention group and 58% of the control group reported productivity loss. The magnitude of productivity loss was 17% and 20%, respectively. At 8 weeks, both the proportion and magnitude of productivity loss were lower in the intervention than the control group, but the differences were statistically significant only at 12 weeks (proportion 25% versus 51%, magnitude 7% versus 18%, P=0.001 for both). Using GEE analyses, we also found the differences to be statistically significant (proportion 38% versus 52%, magnitude 12% versus 18%). The intervention only benefitted employees with 0-20% loss of productivity at baseline, not those with a higher initial productivity loss. CONCLUSIONS: Early ergonomic intervention, in addition to adequate medical care, is effective in preventing and restoring self-reported productivity loss associated with UED.

Results of Finnish national survey on EU legislation concerning computer work.

The European Directive on computer work (VDU 90/270/EEC) is implemented in the Finnish Government Decree. The aim of the present study was to evaluate the effects of the legislation and its applications in practice. The quantitative method used an online questionnaire. The respondents were employers (N=934), employees (N=1872) and occupational health care (OHC) units (N=289). The majority of all these three groups considered the provisions clear and easy to understand, comprehensive, and easy to comply with. The provisions had a great impact on preventing mental overloading, arranging sight tests at the employer's cost, and on the refunding of eyeglasses for computer work. Most employers felt they did not need any more specific provisions, whereas half of the employees and OHC professionals would have liked the provisions to be more detailed. More explicit and specific regulations were also needed for practice applications in particular, as well as for the refunding of the costs of special eyeglasses for computer work. A total of 59% of the employers reported that costs of glasses are refunded, whereas the figure for employees was clearly lower (37%). OHC professionals reported that the costs of glasses were refunded in 82% of their customer workplaces. The practical conclusion is that employees' sight examinations and compensation for eyeglasses should be promoted in computer work. Moreover, ergonomic applications are best carried out in co-operation with OHC personnel.

Effect of a participatory ergonomics intervention on psychosocial factors at work in a randomised controlled trial.

OBJECTIVES: To study the effect of a participatory ergonomics intervention on psychosocial factors among kitchen workers. DESIGN: A cluster randomised controlled trial. SETTING: Four cities in Finland, 2002-2005. PARTICIPANTS: 504 workers in 119 municipal kitchens. INTERVENTION: Kitchens were randomised to intervention (n=59) and control (n=60) groups. The intervention lasted 11-14 months and was based on the workers' active participation in work analysis, planning and implementing the ergonomic changes aimed at decreasing the physical and mental workload. MAIN OUTCOME MEASURES: Mental stress, mental strenuousness of work, hurry, job satisfaction, job control, skill discretion, co-worker relationships and supervisor support. Data were collected by questionnaire at baseline, at the end of the intervention, and at a 12-month follow-up (PI(12)). RESULTS: At the end of the intervention, the OR of job dissatisfaction for the intervention group as compared with the control group was 3.0 (95% CI 1.1 to 8.5), of mental stress 2.3 (1.2 to 4.7) and of poor co-worker relationships 2.3 (1.0 to 5.2). At the PI(12), the OR of job dissatisfaction was 3.0 (1.2 to 7.8). Analysis of the independent and joint effects of the intervention and unconnected organisational reforms showed that adverse changes were accentuated among those with exposure to both. CONCLUSIONS: No favourable effects on psychosocial factors at work were found. The adverse changes were due to a joint effect of the intervention and the unconnected organisational reforms. The findings do not support the usefulness of this kind of intervention in changing unsatisfactory psychosocial working conditions.

Self-reported productivity loss among workers with upper extremity disorders.

OBJECTIVE: Upper extremity disorders (UED) are prevalent in working populations. This study investigates the prevalence, magnitude, and associated factors of on-the-job productivity loss among workers with UED. METHODS: Workers with incipient upper extremity symptoms were invited to participate in our study after the disorder was verified by a physician and no immediate sick leave was required. Of the 177 eligible patients, 168 (95%) were included in the study. They were asked to describe their symptoms, personal characteristics, and work-related factors. Self-assessed productivity measured the impact of UED on the achieved work output. RESULTS: Of the 168 participants, 56% reported a productivity loss; the average reduction thereof was 34%. Productivity loss was associated with pain intensity [odds ratio (OR) for the third tertile 2.8, 95% confidence interval (95% CI) 1.2-6.5], pain interference with work (OR for the third tertile 5.7, 95% CI 2.2-14.3) and fear-avoidance beliefs (OR 2.8, 95% CI 0.9-8.9). Pain interference with sleep was associated with productivity loss only among those aged 46 years or older, whereas high job strain showed an association with productivity loss only among workers aged 20-45 years. In the younger group, productivity loss was more associated with a combination of any two of the following three factors than the presence of only one: pain intensity, job strain, and physical loads at work. CONCLUSIONS: UED cause substantial loss of productivity at work. The most important associated factors are related to pain and its impact on work and sleep, but also to psychological aspects of pain and work. Our findings suggest that the factors associated with productivity loss differ in younger and older workers.

A video-based observation method to assess musculoskeletal load in kitchen work.

This paper describes a new video-based observation method aimed to assess musculoskeletal load in kitchen work, aspects of its repeatability and validity, and problems confronted by the observers. Two pairs of researchers observed individually 117 video clips recorded in kitchens. Interobserver repeatability was assessed by computing the proportion of agreement and weighted kappa values (kappa(w)). Validity was analyzed by studying the distribution of the assessments over the rating scales and the ratings before and after the interventions, which were compared with expert assessments made from the same intervention targets. The proportion of agreement ranged from 57 to 88%. Interobserver repeatability based on weighted kappa values was mainly good to moderate. The method detected the changes in physical load due to the interventions. Direction of the changes corresponded with the expert assessments. Further development of the method is needed to assess the load on the hands and wrists.

Evaluation of a participatory ergonomic intervention process in kitchen work.

We evaluated a participatory ergonomic intervention process applied in 59 municipal kitchens. In groups of three to five kitchens, the workers participated in eight workshops, and generated and evaluated solutions to optimize musculoskeletal load in their work. An ergonomist initiated and supported the process. By the end, 402 changes were implemented. Evaluative data were collected using research diaries, questionnaires, and focus group interviews. The intervention model proved feasible and the participatory approach was mostly experienced as motivating. The workers' knowledge and awareness of ergonomics increased, which improved their ability to tackle ergonomic problems by themselves. The changes in ergonomics were perceived to decrease physical load and improve musculoskeletal health. As hindering factors for implementation, lack of time and motivation, and insufficient financial resources were mentioned. In addition, the workers expressed a wish for more support from the management, technical staff, and ergonomists.

Effectiveness of early part-time sick leave in musculoskeletal disorders.

BACKGROUND: The importance of staying active instead of bed rest has been acknowledged in the management of musculoskeletal disorders (MSDs). This emphasizes the potential benefits of adjusting work to fit the employee's remaining work ability. Despite part-time sick leave being an official option in many countries, its effectiveness has not been studied yet. We have designed a randomized controlled study to assess the health effects of early part-time sick leave compared to conventional full-day sick leave. Our hypothesis is that if work time is temporarily reduced and work load adjusted at the early stages of disability, employees with MSDs will have less disability days and faster return to regular work duties than employees on a conventional sick leave. METHODS/DESIGN: The study population will consist of 600 employees, who seek medical advice from an occupational physician due to musculoskeletal pain. The inclusion requires that they have not been on a sick leave for longer than 14 days prior to the visit. Based on the physician's judgement, the severity of the symptoms must indicate a need for conventional sick leave, but the employee is considered to be able to work part-time without any additional risk. Half of the employees are randomly allocated to part-time sick leave group and their work time is reduced by 40-60%, whereas in the control group work load is totally eliminated with conventional sick leave. The main outcomes are the number of days from the initial visit to return to regular work activities, and the total number of sick leave days during 12 and 24 months of follow-up. The costs and benefits as well as the feasibility of early part-time sick leave will also be evaluated. CONCLUSION: This is the first randomised trial to our knowledge on the effectiveness of early part-time sick leave compared to conventional full-time sick leave in the management of MSDs. The data collection continues until 2011, but preliminary results on the feasibility of part-time sick leave will be available already in 2008. The increased knowledge will assist in better decision making process regarding the management of disability related to MSDs. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number Register, register number ISRCTN30911719.

Expert assessment of physical ergonomics at video-display unit workstations: repeatability, validity and responsiveness to changes.

AIMS: Inter-observer repeatability, validity and responsiveness to change were determined for an expert assessment method for video-display unit (VDU) workstation ergonomics. The aim was to determine to what extent the expert assessment of ergonomics is related to the technical measurements, tidiness and space, work chair ergonomics and responds to changes in these characteristics. METHODS: Technical measurements and video-recordings before and 2 months after an ergonomic intervention were made for 109 VDU office workstations. Two experts in ergonomics analysed and rated the ergonomics of the workstations. A researcher analysed tidiness and available space. A physiotherapist classified the work chairs used according to their ergonomic properties. RESULTS: The intra-class correlation coefficient between the workstation ergonomic ratings of the two experts was 0.74 at the baseline and 0.81 at the follow-up. Workstation tidiness and space, and work chair ergonomics, had a strong effect on the assessments of both experts. For both experts a change in the locations of the mouse, the screen and the keyboard and values of tidiness and space and work chair ergonomics during the intervention showed a significant association with the ratings. CONCLUSION: The assessment method studied can be utilized by an expert in a repeatable manner both in cross-sectional and in longitudinal settings.

Effects of ergonomic intervention in work with video display units.

OBJECTIVES: This study evaluated the effect of an intensive ergonomic approach and education on workstation changes and musculoskeletal disorders among workers who used a video display unit (VDU). METHODS: A randomized controlled design was used. The subjects (N=124) were allocated into three groups (intensive ergonomics, ergonomic education, reference) using stratified random sampling. The evaluation involved questionnaires, a diary of discomfort, measurements of workload, and an ergonomic rating of the workstations. The assessments were made 2 weeks before the intervention and after 2 and 10 months of follow-up. RESULTS: The intensive and training groups showed less musculoskeletal discomfort than the reference group after 2 months of follow-up. Positive effects on discomfort were seen primarily for the shoulder, neck, and upper back areas. No significant differences were found for the strain levels or prevalence of pain. After the intervention the ergonomic level was distinctly higher in the intensive ergonomic group than in the education or reference group. CONCLUSIONS: Both the intensive ergonomics approach and education in ergonomics help reduce discomfort in VDU work. In attempts to improve the physical ergonomics of VDU workstations, the best result will be achieved with cooperative planning in which both workers and practitioners are actively involved.