Computer-telephone interactive tasks: predictors of musculoskeletal disorders according to work analysis and workers' perception

Sixty-two workers engaged in computer-telephone interactive tasks in an active telemarketing center and a telephone call center of an international bank subsidiary in S?o Paulo. Brazil, were assessed by means of a work analysis and a self-administered questionnaire aiming to determine the statistical relationship of ergonomic, organizational and psychosocial characteristics of their jobs with the report of symptoms in neck-shoulder and hand-wrist for more than 7 consecutive days and any time away from work during the current job due to musculoskeletal disorders (MSD). According to chi-square univariate tests and multiple logistic regression models, active telemarketing operations, duration in the job and the low level of satisfaction with the physical arrangement of the workstation emerged as the factors most related to neck-shoulder and hand-wrist MSD and MSD-induced time away from work. This study emphasizes the role of psychosocial factors and duration in the job in MSD occurrence and induced absenteeism among workers engaged in computer-telephone interactive tasks.     

Developing a comprehensive approach to risk management of musculoskeletal disorders in non-nursing health care sector employees

This study of selected jobs in the health care sector explored a range of physical and psychosocial factors to identify those that most strongly predicted work-related musculoskeletal disorders (WMSD) risk. A self-report survey was used to collect data on physical and psychosocial risk factors from employees in three health care organisations in Victoria, Australia. Multivariate analyses demonstrated the importance of both psychosocial and physical hazards in predicting WMSD risk and provides evidence for risk management of WMSDs to incorporate a more comprehensive and integrated approach. Use of a risk management toolkit is recommended to address WMSD risk in the workplace.     

Musculoskeletal disorders among visual display terminal workers: individual,ergonomic, and work organizational factors

A number of individual, ergonomic, and organizational factors of presumed importance for the occurrence of musculoskeletal disorders were investigated in a group of 260 visual display terminal (VDT) workers. The cross-sectional study utilized medical and workplace investigations as well as questionnaires. The results were subjected to a multivariate analysis in order to find the major factors associated with various upper-body muscular problems. Several such factors were identified for each investigated type of musculoskeletal problem. Some were related to the individual: age, gender, woman with children at home, use of spectacles, smoking, stomach-related stress reactions, and negative affectivity. Organizational variables of importance were opportunities for flexible rest breaks, extreme peer contacts, task flexibility, and overtime. Identified ergonomic variables were static work posture, hand position, use of lower arm support, repeated work movements, and keyboard or VDT vertical position.     

Legal system and its effect for prevention of work-related musculoskeletal disorders in Korea

This study aims to introduce the legislation of occupational safety and health regulations for prevention of WMSDs in Korea and investigate its effect by showing an ergonomic intervention effort in a major motor company. In Korea, WMSDs incidence rates had increased from 1999 to 2003, and it is noted that its increment jumped rapidly in 2002 and 2003. The Korean government established a law prescribing employers’ duty of preventing WMSDs in 2002, which began effective in July, 2003. Following the legislation, all employers should execute the examination of WMSDs risk factors for the eleven designated tasks every three years. In addition to this legal obligation, some large companies voluntarily established an ergonomic intervention program by carrying out in-depth assessments for stressful tasks using OWAS, RULA, NLE, etc. We introduce a major motor company case to illustrate the industry’s activities of fulfilling the legislative requirement and of performing ergonomic assessments. Thanks to Korean government and industry’s effort for prevention of WMSDs, the incidence rates of WMSDs have continually decreased from the year of 2004, right after the year when the WMSDs-related regulation was enforced.

Relevance to industry

In spite of booming of information technology industries and automation of manufacturing processes in Korea, many workers are still exposed to the risk of WMSDs including awkward postures, stressful force exertions, repetitive motions in manufacturing and agriculture industries. WMSDs cases alone constitute 43.1% of occupational diseases in Korea and the industry’s effort of ergonomic intervention of WMSDs becomes a major issue to both the management and the labor union.     

Prevention of musculoskeletal disorders at work: Validation and reliability in a multicenter intervention study

During the years 1986–1989 The Finnish Work Environment Fund initiated a multicenter, intervention study (programme) to prevent musculoskeletal disorders at work. The programme consisted of four different projects comprising methodological, epidemiological, and interventive themes. The main results were as follows: (1) More than half of the occupational physiotherapists and physicians involved in the project felt that they did not have adequate training for testing the performance capacity of the musculoskeletal system. Several of the most commonly used musculoskeletal tests had either poor validity in predicting future musculoskeletal troubles or had poor reliability. (2) A controlled intervention study showed that active training of neck-shoulder muscles can prevent musculoskeletal troubles, even more than ergonomic actions. (3) It is possible to reduce sick-leave due to low-back disorders by intervention measures directed toward both the work (environment, tools) and the workers (working methods, positive attitude to work, preparedness to keep fit). (4) The identification of ergonomic hazards with the help of teamwork proved to be feasible. The practical improvements, however, were difficult to implement in the prevailing conditions. Some of the improvements increased the work load and the stress of the workers. This aspect needs further consideration.     

Relationship between work constraints and the development of musculoskeletal disorders of the wrist: A prospective study

A 2-year prospective study was conducted on 184 workers about the relationship between the development of musculoskeletal wrist disorders (WD) and the occupational constraint parameters at their job (wrist angles, forces, repetitiveness and angular velocities), taking into account personal and occupational confounding factors. The results demonstrate a greater probability of developing WD for the workers suffering from chronic diseases, from psychological disorders, practising a sport involving the upper limbs and judging their work tiring.All occupational constraint factors are correlated except for the angles. Logistic correlation analyses show that the most significant associations with a greater probability of developing WD are observed for the mean relative EMG value recorded on the finger and hand flexors and the time during which the velocity in flexion–extension is greater than 50°/s. None of the angular parameters shows any association.Relevance to industryThe study shows that the main factor on which to act in order to reduce the risk of WD is clearly the forces exerted by the hand.The objective of the control measures should be to reduce the muscular activity of the finger and hand flexors below 15% of the maximum activity corresponding to the maximum voluntary contraction of the finger flexors.A reduction of these forces appears to be associated with a reduction of the angular velocities of the wrist and of the repetitiveness.     

Investigation of musculoskeletal symptoms and ergonomic risk factors among female sewing machine operators in Turkey

This cross-sectional study aimed to identify the prevalence of musculoskeletal symptoms and ergonomic risks in female sewing machine operators at a textile company. The study sample comprised all female sewing machine operators in the company. The sample included 283 sewing machine operators. Data were collected through the use of the adapted Nordic Musculoskeletal Questionnaire and by direct observations via the rapid upper limb assessment (RULA) to determine ergonomic risks. RULA is a validated tool for assessment of ergonomic risks. The mean age of the women was 30.2 (SD: 8.4) and the mean number of years of employment was 13.4 (SD: 5.5). The highest prevalence rates for the women’s musculoskeletal symptoms were in the trunk (62.5%), neck (50.5%), and shoulder (50.2%). Of the women, 65% had experienced musculoskeletal pain or discomfort over the last 6 months. Pain intensity of these symptoms was assessed with a visual analogue scale. The average pain intensity of the women was found to be 3.5 (SD: 2.8). Results of the RULA scores were found to be quite high. There were no employees who received RULA scores of 1–2, which indicates acceptable postures (all scores >5). The final RULA scores of 6.9 indicate that the participants’ postures at their work stations need to be investigated immediately.

Relevance to industry

This study based on the RULA method allowed to perform a rapid and quite correct evaluation tolls for SMOs. For this research population, the research findings provided fundamental data on the prevalence of musculoskeletal symptoms and ergonomic risks among Turkish female SMOs.     

Analysis of worker strategies: A comprehensive understanding for the prevention of work related musculoskeletal disorders

By documenting the strategies developed by food processing workers to manage their musculoskeletal pain and discomfort in order to remain on the job, the present article seeks to increase awareness of a different “way of approaching” WMSDs inspired by the ergonomic approach centred on work activity analysis. Based on a mixed methods approach, an ergonomic work activity study combined with a multiple case study was conducted. Sixteen female seafood-processing workers were followed up during two consecutive work seasons using a range of interviews as well as observations of work activity throughout the entire study. A large variety of musculoskeletal pain management strategies developed by those workers to remain on the job were identified. This identification and the process of categorizing the strategies led to the development of a framework for studying worker strategies. The mixed methods approach made it possible to better pinpoint and understand obstacles to the development of workplace strategies and then identify avenues for change to improve working conditions.Relevance to industryThe framework constitutes a valuable contribution for the prevention of WMSDs by representing a methodological tool for documenting worker strategies. Very few tools of this kind are currently available for practitioners and researchers. In becoming aware of the existence of such coping strategies, companies can gain a better understanding of the difficulties workers have to cope with.     

Quantitative and qualitative assessment of musculoskeletal disorders and socioeconomic issues of workers of brick industry in Pakistan

Brick industry, in Pakistan, is prominent and provides job to 3.1 million people only in one province. The industry hires different percentage of workers for different stages of brick formation and these stages trigger musculoskeletal disorders (MSDs) in workers. This study identifies relation between 5 work stages and MSDs in 9 body parts and also finds socioeconomic sufferings inflicted by the industry and removal of research gap at national level. We conducted both qualitative and quantitative research. 105 men and 45 women from 15 brick kilns were selected as subject. Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA) sheets, Standard Nordic MSDs Questionnaire along with general questionnaire, still photography and video recording were used to carry out the study. About 96% workers involved in mixing & molding complained tiredness at end of day. Similarly, 90% male and 83% female staff performing spreading task suffered tiredness after their duty hours. Workers engaged in different tasks reported varying levels of pain in observed body parts. Digging and carrying jobs caused significant pain in body parts including neck, upper back, shoulders, lower back and hips. Mixing and molding emerged most dangerous activities for most of the body parts and exhibited 7 score on RULA. Furthermore, mixing and molding demonstrated high to very high risk level by showing 9 and 13 higher score on REBA, respectively. The current study divulged that all observed work tasks during manufacturing and transportation of bricks are equally dangerous for pain generation in lower back. Many socioeconomic issues like residency of workers in muddy house (83%) low monthly income (<90.3 $) of 83% workers, higher tendency of alcoholism and smoking in men, lack of health facilities and higher illiteracy rate were also identified. The enhanced musculoskeletal disorders during brick making process render the brick industry unhealthy for work. This dismal picture requires an improvement in quality of life and occupational environment of workers of the industry. Well organized duty timings, modified working posture, job rotation and preliminary training perhaps manage these miseries and the output of the brick industry may increase many fold.     

Evaluation of ergonomic approach and musculoskeletal disorders in two different organizations in a truck assembly plant

The aim of this study was to assess the ergonomic physical exposure, organizational and psychosocial factors in a truck assembly plant for two different cycle times (11 min and 8 min). A self-reported questionnaire was applied to evaluate subjective physical exposure, organizational and psychosocial factors by operators in two organization of an assembly process. The initial cycle time was 11 min (system A) and the new was 8 min (system B). The same work and assembly tasks had to be completed in both systems. However, the organization and distribution of the tasks and workstations were reorganized. The results of the questionnaire showed that subjective estimation by the operators regarding ergonomic risk factors was better in the new organization and self-reported WR-MSDs symptoms were fewer. However, exposure to risk factors and WR-MSDs symptoms was not statistically different between two cycle times. The findings provide better understanding of how organizational changes can modify ergonomic exposure in manufacturing assembly industries. Effective interventions are thus not only engineering solutions but also organizational and administrative adaptations.     

Distress and worry as mediators in the relationship between psychosocial risks and upper body musculoskeletal complaints in highly automated manufacturing

As a result of changes in manufacturing including an upward trend in automation and the advent of the fourth industrial revolution, the requirement for supervisory monitoring and consequently, cognitive demand has increased in automated manufacturing. The incidence of musculoskeletal disorders has also increased in the manufacturing sector. A model was developed based on survey data to test if distress and worry mediate the relationship between psychosocial factors (job control, cognitive demand, social isolation and skill discretion), stress states and symptoms of upper body musculoskeletal disorders in highly automated manufacturing companies (n = 235). These constructs facilitated the development of a statistically significant model (RMSEA 0.057, TLI 0.924, CFI 0.935). Cognitive demand was shown to be related to higher distress in employees, and distress to a higher incidence of self-reported shoulder and lower back symptoms. The mediation model incorporating stress states (distress, worry) as mediators is a novel approach in linking psychosocial risks to musculoskeletal disorders.

Practitioners’ Summary

With little requirement for physical work in many modern automated manufacturing workplaces, there is often minimal management focus on Work-Related Musculoskeletal Disorders (WRMSDs) as important occupational health problems. Our model provides evidence that psychosocial factors are important risk factors in symptoms of WRMSD and should be managed.     

Effectiveness of a participatory ergonomics intervention in improving communication and psychosocial exposures

A participatory ergonomics programme was implemented in an automotive parts manufacturing factory in which an ergonomics change team was formed, composed of members from management, the organized labour union and the research team. It was hypothesized that the participatory nature of this change process would result in enhanced worker perceptions of workplace communication dynamics, decision latitude and influence, which in conjunction with anticipated mechanical exposure reductions would lead to reduced worker pain severity. Utilizing a sister plant in the corporation as a referent group, a quasi-experimental design was employed with a longitudinal, repeat questionnaire approach to document pre-post intervention changes. Nine participatory activities (psychosocial interventions) were implemented as part of the process. Communication dynamics regarding ergonomics were significantly enhanced at the intervention plant compared to the referent plant. However, there were no significantly different changes in worker perceptions of decision latitude or influence between the two plants, nor did pain severity change. Possible explanations for these results include limited intervention intensity, context and co-intervention differences between the two plants, high plant turnover reducing the statistical power of the study and lack of sensitivity and specificity in the psychosocial measures used. Further research should include the development of psychosocial tools more specific to participatory ergonomic interventions and the assessment of the extent of change in psychosocial factors that might be associated with improvements in pain.     

Risk of neck musculoskeletal disorders among males and females in lifting exertions

Work-related neck disorders are common among various occupational groups. Despite clear epidemiological evidence for the association of these disorders with forceful arm exertions, the effect of such exertions on the biomechanical behavior of the neck muscles is currently not well understood. In this study, the effect of lifting tasks on the biomechanical loading of neck muscles was investigated for males and females. Twenty-six participants (13 males and 13 females) performed bi-manual isometric lifting tasks at knuckle, elbow, shoulder, and overhead heights by exerting 25%, 50%, and 75% of their maximum strength. The activity of the cervical trapezius and sternocleidomastoid muscles was recorded bilaterally using surface electromyography. Higher activity of the cervical trapezius muscle (10% MVC–43% MVC) compared to the sternocleidomastoid muscle (4% MVC–18% MVC) was observed. Females tend to use the sternocleidomastoid muscle to a greater extent than males, whereas, higher cervical trapezius muscle activation was observed for males than females. The main effect of weight and height, and weight by height interaction on the activity of neck muscles was statistically significant (all p < 0.001). The results of this study demonstrate that the neck muscles play an active role during lifting activities and may influence development of musculoskeletal disorders due to resulting physiological changes.     

Study protocol and baseline results for a quasi-randomized control trial: An investigation on the effects of ergonomic interventions on work-related musculoskeletal disorders,quality of work-life and productivity in knowledge-based companies

IntroductionWork-related musculoskeletal disorders (WMSDs) are the major causes of lost workdays, increased costs, and occupational diseases in all countries. The prevalence of WMSDs among the workers in small and medium-sized enterprises in Iran was reported as 73%. This paper aimed to describe the design of an interventional study to investigate the effects of ergonomic interventions on work-related musculoskeletal disorders, quality of work-life, and productivity among office workers of knowledge-based companies and introduce the results obtained from the baseline survey.Methods/designIt was a quasi-randomized control trial study on 313 participants with four parallel groups including ergonomic training intervention; management training and work changes intervention; ergonomic training, management training and work changes intervention; and non-interventional control group. The primary outcome was WMSDs, and the secondary outcomes were occupational stress factors, quality of work-life, and productivity. All primary and secondary outcomes were measured before the interventions, one, three, and six months after the interventions.ResultsAt this phase of study only baseline results were reported. 328 participants, with a mean age of 31.97 years (SD = 5.39), completed the baseline survey and entered the study. The highest prevalence of musculoskeletal disorders was found in neck (52.13%), right shoulder (41.16%) and right forearm (37.2%), respectively.ConclusionErgonomic interventions were conducted based on baseline data of the participants at individual and management levels. The focus of training program interventions was to reduce musculoskeletal disorders in upper limbs; in management training and work changes program, the focus was to increase social support.Trial registrationIRCT registration number: IRCT20181204041840N1 (date of registration: 2019-02-05).     

A multilayered ergonomic intervention program on reducing musculoskeletal disorders in an industrial complex: A dynamic participatory approach

Work-related musculoskeletal disorders (WMSDs) are closely identified with common complaints in different workplaces. This study aimed to implement an intervention program through which ergonomic measures were dynamically localized in industry. An interventional study, including three basic layers, namely, training workshops, participatory ergonomics (PE), and workstation redesign was fulfilled in an Iranian steel manufacturing complex from 2017 to 2020. A steering committee (SC) was formed following several meetings held for clarification of the project to the management team. The SC members then attended four organized workshops managed by an ergonomics specialist. Afterwards, the basics of ergonomics were transferred to action groups. After developing ergonomic assessment tools, the ergonomic problems were prioritized and numerous positive changes were made by the action groups. The findings of the tailored checklists revealed a load of WMSDs risk factors. All the three layers of the program were implemented as initiated. Ergonomics training workshops were then held and significant differences were observed between the participants' pre/posttest mean scores in all workshops (p < 0.001). Moreover, PE measures were exercised at all levels of the organization inducing enthusiastic motivation of the workforce to consider ergonomic requirements in the workplace. Consequently, the workers' innovative ideas and the managerial support yielded diverse workstation redesigns due to a growth in either the workers' ergonomics awareness or participatory culture grounding. A multilayered ergonomic intervention was implemented in this study. In conclusion, a multifaceted long-term follow-up intervention program could be applied to enhance workers’ health status and to raise system productivity.     

Muscular effort and musculoskeletal disorders in piano students: electromyographic,clinical and preventive aspects

Abstract

An investigation was made on the relationship between music practice and musculoskeletal disorders among piano students, with the main aim of developing health education programmes that would improve the performance and health of the students.

The investigation covered three areas

(a) Analysis of study organization and main musculoskeletal complaints achieved by a questionnaire distributed to all piano students at the Milan Conservatory.

(b) Vocational electromyographic analysis of the effort exerted by the various muscle groups of the trunk, of the shoulder and shoulder blade girdle, and of the arm during performance of a standard set of piano exercises, an unseen passage and a passage of maximum difficulty. This analysis was made on a sample of six subjects.

(c) A series of preventive measures was developed on the basis of a critical assessment of the results (38% of the students practised for excessively long periods without breaks; 62% had from 1 to 5 complaints, the most affected sites being the spine and the trapezius muscles). These consisted largely of a health education programme aimed at helping the students to suitably organize practice and rest periods and in instructing them in appropriate exercises for relaxation and stretching of overused muscle groups and strengthening the supporting muscle groups. Changes in lifestyle were also suggested.     

A case study of Taiwanese custom-beverage workers for their musculoskeletal disorders symptoms and wrist movements during shaking task

This study administered the Nordic Musculoskeletal Questionnaire to a convenience sample of 106 workers at custom-beverage vendors in Taiwan (who prepare drinks through manual shaking) to explore their work-related musculoskeletal disorders (WMSDs) and identify risk factors for these disorders symptoms. Wrist posture for twenty workers were also measured for three shaking methods using an electrogoniometer. The prevalence of musculoskeletal discomfort in the past year among the respondents was 88.6%. Most of them reported discomfort in their hands/wrists (67.9%), followed by the lower back/waist (44.3%), knees (39.6%), and shoulders (38.7%). Hands/wrists and low back/waist discomforts varied significantly by the worker's gender and the number of working days per week, and hands/wrists discomfort also by the shaking method. Knee discomfort was affected by age and whether rest periods at work were scheduled, whereas shoulder discomfort by work experience, number of working days per week, and number of drink orders prepared per day. Measurements in wrist postures exhibited that repetitive activity for each wrist was as high as 4 time/s for a cup preparation (10 s). Among shaking methods, curve swing can constrain the shakers' wrists in a relatively neutral position and a smaller range of movement than others, regardless of the sex.Relevance to industryBecause of the nature of shaking-based beverage preparation work, the respondents have a higher prevalence of discomfort in the hands/wrists, lower back/waist, knees, and legs/ankles than their counterparts in other industries. These findings are expected to inform the prevention and alleviation of musculoskeletal discomfort in custom-beverage workers.     

Work-related musculoskeletal disorders in home care nurses: Study of the main risk factors

BackgroundNurses are a risk group for work-related musculoskeletal disorders (WMSDs). Several studies reveal that nurses have high prevalence rates of injuries and symptoms related to WMSDs. However, many of these studies focus mostly on hospital nurses. Worldwide, few studies include home care nurses.ObjectiveThis work aimed to identify the body region most affected by musculoskeletal complaints in home care nursing, and subsequently develop a statistical model, that includes the main risk factors, to predict the risk of having musculoskeletal complaints in the identified region.MethodsThe research method was based on the Standardised Nordic Questionnaire applied to home care nurses working at Health Centres of northern Portugal. Univariate and multivariate models of logistic regression were used to meet the goals of this work.ResultsHome care nurses have a three times greater chance of having lumbar complaints than their counterparts working only at Health Centres (OR = 3.19 (p < 0.05), with a 95% confidence interval [1.256; 8.076]). A statistical model with seven variables (forearm posture; static postures; arm posture; arm supported; bed height; job satisfaction; assistive devices) was obtained to predict lumbar complaints.ConclusionsThe lumbar region was identified as the most affected by musculoskeletal complaints. These complaints were associated with seven factors.     

Perceived competence in computer use as a moderator of musculoskeletal strain in VDU work: An ergonomics intervention case

Musculoskeletal strain and other symptoms are common in visual display unit (VDU) work. Psychosocial factors are closely related to the outcome and experience of musculoskeletal strain. The user – computer relationship from the viewpoint of the quality of perceived competence in computer use was assessed as a psychosocial stress indicator. It was assumed that the perceived competence in computer use moderates the experience of musculoskeletal strain and the success of the ergonomics intervention. The participants (n = 124, female 58%, male 42%) worked with VDU for more than 4 h per week. They took part in an ergonomics intervention and were allocated into three groups: intensive; education; and reference group. Musculoskeletal strain, the level of ergonomics of the workstation assessed by the experts in ergonomics and amount of VDU work were estimated at the baseline and at the 10-month follow-up. Age, gender and the perceived competence in computer use were assessed at the baseline. The perceived competence in computer use predicted strain in the upper and the lower part of the body at the follow-up. The interaction effect shows that the intensive ergonomics intervention procedure was the most effective among participants with high perceived competence. The interpretation of the results was that an anxiety-provoking and stressful user – computer relationship prevented the participants from being motivated and from learning in the ergonomics intervention. In the intervention it is important to increase the computer competence along with the improvements of physical workstation and work organization.