Psychosocial risk factors for musculoskeletal disorders (MSDs)
Swenneke van den Heuvel, Netherlands Organisation for Applied Scientific Research
- 1 Introduction
- 2 How psychosocial factors could lead to MSDs
- 3 Evidence for the relationship between psychosocial factors and MSDs
- 4 Prevalence of work-related psychosocial factors
- 5 Psychosocial factors in office workers
- 6 Psychosocial factors in other types of work
- 7 Consequences for intervention strategies
- 8 References
- 9 Links for future readings
It has been known for some time that risk factors in the workplace can have a negative effect on health. Ramazzini was one of the first scientists to identify occupational health hazards. He wrote about diseases of the musculoskeletal system caused by sudden and irregular movements and the adoption of awkward postures. Another category of work-related risk factors for musculoskeletal disorders (MSDs) includes psychosocial work characteristics, such as work demands, job control and social support at work. In earlier studies, these factors were considered as potential confounders when exploring the relationship between physical exposure and symptoms. More recently psychosocial factors are considered to be independent risk factors.
There are no globally accepted definitions of work-related psychosocial factors. In general, work-related psychosocial factors refer to individual subjective perceptions of the organisation of work, such as hours worked, work-rest cycles, culture, and management style. They often carry emotional value and have the potential for causing physical or psychological damage to health. A similar description is provided by the European Agency for Safety and Health at Work: “Psychosocial risks are linked to the way work is designed, organised and managed, as well as to the economic and social context of work, result in an increased level of stress and can lead to serious deterioration of mental and physical health”. The Health and Safety Executive, UK, distinguishes between the following categories of psychosocial risk factors in the workplace:
- Demands – poorly designed/managed workload, work scheduling, work organisation, job design and physical environment.
- Control – lack of skill discretion and lack of authority.
- Support – inappropriate proactive and reactive support, failure to match people’s skills with their job, failure to take account of other individual factors.
- Relationships – poorly designed/managed procedures for eliminating damaging conflict at individual/team level (bullying, harassment).
- Role – role conflict, inappropriate levels of role ambiguity, inappropriate levels of responsibility.
- Change – a lack of planned, active strategy for change, poorly designed/managed strategies for overcoming resistance, a lack of appropriate consultation with employees over concerning change, a lack of appropriate support for employees, poorly designed/managed new ways of working or new technology.
In the scientific literature, adverse health effects of psychosocial factors at work are often attributed to a combination of different factors. The most widely known is Karasek’s demand-control-support model. According to this model, the risk of adverse health effects, in particular stress) will increase if high job demands are combined with low control. A low level of support will increase the adverse effects of the combination of high demand and low control. Another well-known model combining different work-related psychosocial factors is Siegrist’s Effort-Reward Imbalance (ERI) model. The assumption of the ERI-model is that an imbalance between efforts and rewards leads to adverse health effects.
Psychosocial factors are often associated with stress. Nevertheless, several studies have demonstrated that they also have an effect on MSDs. There are several possible pathways through mechanisms by which psychosocial factors could lead to MSDs. The two most important pathways mechanisms will be mentioned here. The possible associations between psychosocial factors and MSDs are illustrated by in Figure 1.
One possible mechanism by which psychosocial factors at work may influence MSDs, is by exposing workers to unfavourable physical factors. In particular high job demands may have the effect of an increasing exposure to harmful physical working conditions, or to prolonged physical inactivity in some occupations. This increased exposure will be caused, in part, by the longer working hours needed to cope with higher job demands. However, higher job demands could also lead to a less favourable work style. This work style could be characterised by taking fewer rest breaks, but also by awkward postures, movements or exposure to forces. High job demands may alter the way in which work is conducted and increase the mechanical load. For example, a task may be carried out in an unfavourable way, such as hurried movements and/or carrying more weight in order to get the work done more quickly.
Secondly, the relationship between psychosocial factors and MSDs could be mediated by stress symptoms. Stress creates physiological responses which have been the subject of a large body of research. Initially, authors described a ‘fight or flight’ reaction in animals during situations where they either had to flee or prepare to fight in order to defend themselves from danger. Fight or flight reactions have also been found to occur in humans during times of stress or danger. These are not confined to a behavioural response, but refer explicitly to physiological responses, such as dilation of the pupils, increased heart rate, the release of adrenaline and cortisol into the bloodstream.
Translated to the reality of the workplace, work-related psychosocial factors can lead to stress and like a perceived threat to our survival, this stress will evoke physiological responses and may cause musculoskeletal symptoms. Stress may increase the tone in muscles causing them to become fatigued, or it may increase the duration of muscle activity and reduce the likelihood for recovery. Stress may also intensify the perception of pain, or undermine the mechanisms used to cope with pain. Also, stress may modify the physical and behavioural responses to pain. Seen from a more pathophysiological perspective, stress may, apart from increasing muscle activity, impair circulation and the supply of oxygen to tissues as a result of hyperventilation. Moreover, prolonged stress may degrade tissue quality and the ability of tissues to recover due to hormonal processes.
Many scientific studies have demonstrated an independent effect of psychosocial risk factors for MSDs. For back pain, the most consistent evidence of adverse health effects exists for high job demands (e.g. high workload and time pressure), low job satisfaction (overall satisfaction with the job) and low job support (colleagues and supervisor willingness to listen and provide assistance). For neck and shoulder pain the most consistent evidence exists for high job demands. Evidence also exists that low job demands – jobs evaluated as monotonous or with insufficient use of skills – appear to be a risk factor for neck and shoulder pain. Many studies have found evidence of the adverse effect of other psychosocial factors, but the results from these studies are not consistent. The relationship between psychosocial factors and pain in the lower extremities is not often examined. Some studies have been carried out on the relationship between psychosocial factors and knee pain. Although there are indications of an adverse effect of job stress, the evidence is insufficient.
With the aim of improving quality of work in Europe, every five years the European Working Conditions Survey (EWCS) is undertaken. The survey collects data on the conditions of the European working population. The most recent survey took place in 2010. One of the questions in the survey is: ‘Does your job involve working to tight deadlines?’ ‘Working to tight deadlines’ was considered to be a component of high job demand. The survey results showed that the percentage of workers who reported their job involved working to tight deadlines for at least a quarter of the time had slightly increased from 59% in 2000, 61.9% in 2005 and 62.1% in 2010. However, data from the most recent EWCS (2015) shows that this figure has declined to a little over half (51.8%) overall. Figure 2 shows that working to tight deadlines differs between occupations, with highly skilled manual workers reporting tight deadlines most frequently. Figure 3 shows that working to tight deadlines is more common in the industrial sector, as opposed to the service sector.
Exposure to physical risk factors differs between occupations and the type of industry. Since psychosocial factors are also different among those groups, it is possible that the relationship between psychosocial factors and MSDs is also different. Nevertheless, many studies examining this relationship do not distinguish between occupations. However, one homogeneous group of workers that has been studied separately is office workers.
Work with computers is becoming increasingly prevalent in Europe; according to the EWCS the percentage of people working with computers for most all of their working day has increased from 17.6% in 2000 to 28.8% in 2010; with a further slight increase to 30.3% in 2015 (proportion working all or almost all of the time with computers, laptops, smartphones, etc.). Since computer-related office work has intensified, attention to health status of office workers and the possible risk factors of computer work has increased. The attention has focused on arm-wrist-hand and neck-shoulder symptoms. Originally, mainly physical risk factors, such as computer use and static postures, were seen as significant contributing factor to the problem. In Australia during the 1980’s an epidemic of “repetitive strain injuries” was reported for office workers after the introduction of computers into the workplace. Repetitive Strain Injury (RSI) was given official medical status in Australia based on the assumption that repetitive tasks involving the arms and hands and/or fixed working postures for extended periods could lead to overuse of soft tissues and resultant arm-wrist-hand and neck-shoulder symptoms.
The lack of objective medical findings (i.e. muscle or nerve damage) among patients, fuelled the medical debate about the origin of the arm-wrist-hand and neck-shoulder symptoms of computer workers. One group accepted the medical explanation: overuse of soft tissues due to repetitive hand-arm tasks and/or fixed working postures. Another group favoured mental and social factors as playing an important role.
In recent years there has been an increase in the number of high quality studies published that investigated the impact of psychosocial factors on MSDs. The interaction between psychosocial and physical factors has been studied, but psychosocial factors were also identified as independent risk factors. Most studies conclude that risk factors for neck-shoulder pain and arm-wrist-hand pain in computer workers consist of a mixture of physical and psychosocial work characteristics.
Many studies investigating psychosocial risk factors and MSDs include mixed populations, with workers from various industries and with different jobs. Therefore, it is not possible to list the industries in which the relationship between psychosocial factors and MSDs has been established, or those in which the relationship is not present or has not yet been examined. Nevertheless, in occupational groups other than office workers, a relationship has be found between psychosocial factors and MSDs.. In workers with monotonous work, an unfavourable effect was found on neck and shoulder pain. A study investigating workers from industrial and service companies found that low job satisfaction predicted neck/shoulder pain and lower limb pain.
In a study investigating workers at automobile repair garages, low decision authority or job control (control over work speed, breaks, decisions etc.) predicted neck pain, low back pain, and total musculoskeletal pain.
In a study among health care workers it was found that an increased risk for compensated musculoskeletal injuries of the lower back and lower limb was related to low job control. These studies illustrate that the effect of psychosocial factors are not limited to office workers.
Consequences for intervention strategies
Findings in the scientific literature emphasise that work-related MSDs arise from multiple risk factors. Apart from biomechanical risk factors, biobehavioural, psychosocial and organisational factors play an important role. Therefore, an integrated approach to prevention seems the most promising strategy. Research has shown that interventions based on single measures appear to be unlikely to prevent MSDs. A holistic approach is needed, covering physical and psychological demands, addressing ergonomic and organisational aspects of work. This approach promises to be most successful if it is embedded in a participatory environment and in a strong prevention-oriented corporate culture.
The integrated approach has also been recommended by the European Trade Union Confederation (ETUC). The ETUC emphasises the need for a comprehensive and integrated approach in relation to a new directive which is aimed at the primary prevention of MSDs. They state that a strategic approach towards MSDs should be comprehensive, multidisciplinary and participative; in particular, it should consider all parts of the human body, and biomechanical and specific work organisation factors – especially the issue of time pressure. Nevertheless, such a strategy has not yet been adopted.
Although the integrated approach has been recommended by scientists and policy makers, little is known of the effect of interventions that include the improvement of psychosocial factors. Very few studies have reported on the preventive effect of these interventions for work related MSDs, and those existing are limited to neck and shoulder pain. However, there is some evidence that, to be successful, a physical ergonomics programme should have an organisational dimension and involvement of the workforce.
Not only primary prevention but also rehabilitation will profit from an integrated approach. This approach is known as multidisciplinary rehabilitation. Favourable results have been found for workers with low back pain. Less is known of the effectiveness of a multidisciplinary rehabilitation programme for neck and shoulder pain. However, considering the multifactorial origin of these symptoms, an integrated approach seems the most promising strategy. Effective treatment programmes appear to contain multiple components, such as knowledge conditioning (e.g. education or information about pain and the human anatomy), psychological conditioning, physical and work conditioning and relaxation exercises. Patients with negative recovery expectations take longer to return to work.
The differences between effective and non-effective treatments could be explained by the fact that effective treatments include psychological and educational strategies which tackle negative expectations more successfully.
In conclusion, both prevention and rehabilitation strategies will profit from a multidisciplinary approach.
- Ramazzini, B. De Moribis artificium diatriba (diseases of workers), 1713.
- Feuerstein, M., Shaw, W.S., Nicholas, R.A., Huang, G.D. From confounders to suspected risk factors: psychosocial factors and work-related upper extremity disorders. Electromyogr Kinesiol, 14, 2004, pp. 171-8.
- Devereux, J., Rydstedt, L., Kelly, V., Weston, P., Buckle, P. The role of work stress and psychological factors in the development of musculoskeletal disorders: The stress and MSD study. HSE Research Report 273, Robens Centre for Health Ergonomics, Guildford, Surrey, 2004
- EU-OSHA – European Agency for Safety and Health at Work. Expert forecast on emerging psychosocial risks related to occupational safety and health (OSH), 2007a. Available at: http://osha.europa.eu/en/publications/factsheets/74
- Karasek, R.A., Theorell, T. Healthy work: stress, productivity, and the reconstruction of working life, New York, Basic Books, 1990.
- Siegrist, J. Adverse health effects of high effort – low reward conditions at work. J Occup Health Psychol, 1, 1996, pp. 27-43.
- Van den Heuvel, S.G. Work related neck and upper limb symptoms. PhD thesis, 2006.
- Cannon, W.B. Bodily Changes in Pain, Hunger, Fear and Rage: An Account of Recent Researches into the Function of Emotional Excitement. Appleton, 1915.
- Palmer, K.T. Regional musculoskeletal conditions: pain in the forearm, wrist and hand. Best Pract Res Clin Rheumatol,17(1), 2003, pp. 113-35.
- Visser, B., van Dieën, J.H. Pathophysiology of upper extremity muscle disorders. J Electromyogr Kinesiol, 16(1), 2006, pp. 1-16.
- National Research Council and the Institute of Medicine. Musculoskeletal disorders and the workplace: Low back and upper extremities. Washington DC: National Academy Press, 2001.
- Macfarlane, G.J., Pallewatte, N., Paudyal, P., Blyth, FM., Coggon, D., Crombez, G., Linton, S., Leino-Arjas, P., Silman, A.J., Smeets, R.J., van der Windt, D. Evaluation of work-related psychosocial factors and regional musculoskeletal pain: results from a EULAR Task Force, Ann Rheum Dis,, 68(6), 2009, pp. 885-91.
- D'Souza, J.C., Franzblau, A., Werner, R.A.. Review of epidemiologic studies on occupational factors and lower extremity musculoskeletal and vascular disorders and symptoms. J Occup Rehabil, 15(2), 2005, pp. 129-65.
- EUROFOUND – European Foundation for the improvement of living and working conditions. EWCS 2010 Survey Results, 2010. Available at: http://www.eurofound.europa.eu/surveys/smt/ewcs/results.htm
- Ijmker, S. Risk factors for arm-wrist-hand and neck-shoulder symptoms among office workers. PhD thesis, 2008.
- Marcus, M., Gerr, F., Monteilh, C., Ortiz, D.J., Gentry, E., Cohen, S., et al. A prospective study of computer users: II. Postural risk factors for musculoskeletal symptoms and disorders. Am J Ind Med, 41, 2002, pp. 236–49.
- Eltayeb, S., Staal, J.B., Hassan, A., de Bie, R.A. Work related risk factors for neck, shoulder and arms complaints: a cohort study among Dutch computer office workers. J Occup Rehabil; 19(4), 2009, pp. 315-22.
- Hannan, L.M., Monteilh, C.P., Gerr, F., Kleinbaum, D.G., Marcus, M. Job strain and risk of musculoskeletal symptoms among a prospective cohort of occupational computer users. Scand J Work Environ Health, 31(5), 2005, pp. 375-86.
- Hush, J.M., Michaleff, Z., Maher, C.G., Refshauge, K. Individual, physical and psychological risk factors for neck pain in Australian office workers: A 1-year longitudinal study. Eur Spine J, 18(10), 2009, pp. 1532-40.
- Krause, N., Burgel, B., Rempel, D. Effort-reward imbalance and one-year change in neck-shoulder and upper extremity pain among call center computer operators. Scand J Work Environ Health, 36(1), 2010, pp. 42-53.
- Lapointe, J., Dionne, C.E., Brisson, C., Montreuil, S. Interaction between postural risk factors and job strain on self-reported musculoskeletal symptoms among users of video display units: a three-year prospective study, Scand J Work Environ Health, 35(2), 2009, pp. 134-44.
- Andersen, J.H., Haahr, J.P., Frost, P. Risk factors for more severe regional musculoskeletal symptoms: A two-year prospective study of a general working population. Arthritis and Rheumatism, 56(4), 2007, pp. 1355-64.
- Torp, S., Riise, T., Moen, B.E. The impact of psychosocial work factors on musculoskeletal pain: A prospective study. J Occup Environ Med, 43(2), 2001, pp. 120-6.
- Koehoorn, M., Demers, P.A., Hertzman, C., Village, J., Kennedy, S.M. Work organization and muscoloskeletal injuries among a cohort of health care workers, Scand J Work Environ Health, 32(4), 2006, pp. 285-93.
- ETUC – European Trade Union Confederation, First stage consultation with social partners on musculoskeletal disorders in the workplace; ETUC response 2005. Available at: http://hesa.etui-rehs.org/uk/newsevents/files/ConsultTMScommR%C3%A9ponseCES-EN.pdf
- Amick, B.C., Kennedy, C.A., Dennerlein, J.T., Brewer, S., Catli, S., Williams, R., Serra, C., Gerr, F., Irvin, E., Mahood, Q., Franzblau, A., Van Eerd, D., Evanoff, B., Rempel, D., Systematic review of the role of occupational health and safety interventions in the prevention of upper extremity musculoskeletal symptoms, signs, disorders, injuries, claims and lost time. Toronto: Institute for Work & Health, 2008.
- Bongers, P.M., IJmker, S., van den Heuvel, S., Blatter, B.M.. Epidemiology of work related neck and upper limb problems: psychosocial and personal risk factors (part I) and effective interventions from a bio behavioural perspective (part II). J Occup Rehabil. 16(3), 2006, pp- 279-302.
- EU-OSHA – European Agency for Safety and Health at Work. Work-related musculoskeletal disorders: prevention report, 2008. Available at: http://osha.europa.eu/en/publications/reports/en_TE8107132ENC.pdf
- EUROFOUND – European Foundation for the improvement of living and working conditions. Managing musculoskeletal disorders. Dublin, Eurofound, 2007. Available at: http://www.eurofound.europa.eu/docs/ewco/tn0611018s/tn0611018s.pdf
- Karjalainen, K., Malmivaara, A., Pohjolainen, T., Hurri, H., Mutanen, P., Rissanen, P., et al. Mini-intervention for subacute low back pain: a randomized controlled trial, Spine, 15, 28(6), 2003, pp. 533-40.
- Williams RM, Westmorland MG, Lin CA, Schmuck G, Creen M. Effectiveness of workplace rehabilitation interventions in the treatment of work-related low back pain: a systematic review. Disabil Rehabil, 30; 29(8), 2007, pp. 607-24.
- EU-OSHA – European Agency for Safety and Health at Work. Work-related musculoskeletal disorders: Back to work report, 2007b. Available at: http://osha.europa.eu/en/publications/reports/7807300
- Meijer, E.M., Sluiter, J.K., Frings-Dresen, M.H.W. Evaluation of effective return-to-work treatment programmes for sick-listed patients with non-specific musculoskeletal complaints: a systematic review. Int Arch Occup Environ Health, 78, 2005, pp. 523-32.
Links for future readings
EU-OSHA –European Agency for Safety and Health at Work. Expert forecast on emerging psychosocial risks related to occupational safety and health (OSH), 2007. Available at: http://osha.europa.eu/en/publications/factsheets/74
EU-OSHA – European Agency for Safety and Health at Work. Work-related musculoskeletal disorders: prevention report, 2008. Available at: http://osha.europa.eu/en/publications/reports/en_TE8107132ENC.pdf
EU-OSHA – European Agency for Safety and Health at Work. Work-related musculoskeletal disorders: prevention report, 2008. A summary. Available at: http://osha.europa.eu/en/publications/factsheets/78
EU-OSHA – European Agency for Safety and Health at Work. Work-related musculoskeletal disorders: Back to work report, 2008. Available at: http://osha.europa.eu/en/publications/reports/7807300
EU-OSHA – European Agency for Safety and Health at Work. Work-related musculoskeletal disorders: Back to work report, 2008. Fact sheet. Available at: http://osha.europa.eu/en/publications/factsheets/75
EU-OSHA – European Agency for Safety and Health at Work. OSH in figures: Stress at work – facts and figures. 2009. Available at: http://osha.europa.eu/en/publications/reports/TE-81-08-478-EN-C_OSH_in_figures_stress_at_work
EU-OSHA – European Agency for Safety and Health at Work. OSH in figures: Work related musculoskeletal disorders in the EU – facts and figures. 2010. Available at: http://osha.europa.eu/en/publications/reports/TERO09009ENC
EU-OSHA – European Agency for Safety and Health at Work. Introduction to work-related musculoskeletal disorders, 2007. Fact sheet. Available at: http://osha.europa.eu/en/publications/factsheets/71
EU-OSHA – European Agency for Safety and Health at Work. Work-related musculoskeletal disorders (MSDs): an introduction, 2007. E-Fact. Available at: http://osha.europa.eu/en/publications/e-facts/efact09
EU-OSHA – European Agency for Safety and Health at Work. Prevention of psychosocial risks and stress at work in practice, 2002. Available at: http://osha.europa.eu/en/publications/reports/104
EU-OSHA – European Agency for Safety and Health at Work. How to tackle psychosocial issues and reduce work-related stress, 2002. Available at: http://osha.europa.eu/en/publications/reports/309
EU-OSHA – European Agency for Safety and Health at Work. How to tackle psychosocial issues and reduce work-related stress, 2002. Fact sheet. Available at: http://osha.europa.eu/en/publications/factsheets/32
EU-OSHA – European Agency for Safety and Health at Work. Practical advice for workers on tackling work-related stress and its causes, 2002. Fact sheet. Available at: http://osha.europa.eu/en/publications/factsheets/31
EU-OSHA – European Agency for Safety and Health at Work. Work related stress, 2002. Fact sheet. Available at: http://osha.europa.eu/en/publications/factsheets/22
EU-OSHA – European Agency for Safety and Health at Work. Stress at work: Summary of an Agency report, 2002. Fact sheet. Available at: http://osha.europa.eu/en/publications/factsheets/8
EU-OSHA – European Agency for Safety and Health at Work. Hazards and risks leading to work-related neck and upper limb disorders, 2007. E-fact. Available at: http://osha.europa.eu/en/publications/e-facts/efact16
EU-OSHA – European Agency for Safety and Health at Work, Musculoskeletal disorders (website, no publishing date available). Retrieved on June 2011, from: http://osha.europa.eu/en/topics/msds/index_html
EU-OSHA – European Agency for Safety and Health at Work, Work on Stress. (website, no publishing date available). Retrieved on June 2011, from: http://osha.europa.eu/en/topics/stress