Duration of computer use and mouse use in relation to musculoskeletal disorders of neck or upper limb

https://doi.org/10.1016/S0169-8141(02)00132-4Get rights and content

Abstract

The objectives of this study were to examine the association between work-related upper limb disorders (WRULDs) and duration of computer and mouse use, to investigate differences in these associations between men and women, and to examine whether a possible relationship between duration of computer use and WRULDs was explained by physical or psychosocial risk factors. The study population in this cross-sectional questionnaire study consisted of 5400 office employees. Participants had filled out a questionnaire on job characteristics, job content, physical workload, psychosocial workload and musculoskeletal symptoms.

Working with a computer during more than 6 h/day was associated with WRULDs in all body regions. Stratified analyses showed that the strength of the associations differed between men and women. In men, only moderate associations were seen for computer use more than 6 h/day. In women, moderately increased ORs were observed for a duration of computer use of more than 4 h/day and strongly increased risks for a computer use during more than 6 h/day.

Frequent computer users who often used a mouse did not report more WRULDs or neck or shoulder disorders than frequent computer users who did not use a mouse. Only for arm, elbow or wrist or hand problems a moderately increased OR among the mouse users was observed, but this was not statistically significant.

Relevance to industry

Recent increases in the number of employees working with computers and in the durations of computer and mouse use coincide with a huge prevalence increase of work-related disorders of neck and upper limb (WRULDs) and sick leave, which poses financial burdens on companies. Research on risk factors and preventive measures is relevant for these companies.

Introduction

In the past few years, impressive developments have taken place regarding information and communication technology. In addition to the positive effects of these technologies, such as an increase in efficiency, accessibility of data and communication velocity, potential adverse effects must not be overlooked. Increase of computer work coincided with a huge prevalence increase of work-related disorders of neck and upper limb (WRULDs). In The Netherlands, the proportion of workers performing computer work more than 50% of their time is not only very high compared to other European countries (41% in The Netherlands, compared to 32% in the UK, 27% in Belgium and 9% in Greece), but also showed a larger increase between 1991 and 1996 than in other countries (Houtman and Kwantes, 1999).

The effects of computer work have been reviewed by Punnett and Bergqvist (1997). An extensive review of 56 epidemiological studies on computer work and upper extremity musculoskeletal problems was performed, a part of which studied the relationship between duration of computer work or keying and symptoms (Bergqvist et al., 1992; Bernard et al., 1994; Evans, 1987; Faucett and Rempel, 1994; Hales et al., 1994; Jeyaratnam et al., 1989; Kamwendo et al., 1991; Knave et al., 1985; Marcus and Gerr, 1996; Oxenburgh, 1987; Rossignol et al., 1987; Sauter, 1984). Punnett and Bergqvist concluded from these studies that for hand and wrist disorders, use of computer or keyboard was a direct causative agent. The odds among VDU users with at least 4 h of keyboard work was twice that of those with little or no keyboard work. Neck and shoulder disorders were also found to be associated with VDU work, but less consistently than hand and wrist disorders. High work demands and postural stress resulting from poor work-station design also increased the risk of WRULD (Punnett and Bergqvist, 1997).

The number of studies that have examined the impact of mouse use on musculoskeletal health is limited. Most of these studies only include experiments with small numbers and short-term effects, such as discomfort and muscle activity (Punnett and Bergqvist, 1997). Mouse users seem to work with more extreme wrist and shoulder postures than non-mouse users (Karlqvist et al., 1994). Jensen et al. (1998) concluded from a study among CAD users that musculoskeletal symptoms were far more prevalent for the arm or hand operating the mouse than for the other arm or hand. Keir et al. (1999) measured carpal tunnel pressure of 14 participants using three different mice. Using a mouse increased the carpal tunnel pressure as opposed to resting the hand on the mouse. No differences were observed between the three mice.

In this study, the distribution of duration of computer and mouse use, computer-related physical factors and psychosocial factors among several different office workers is described first, as well as the distribution of the 1 yr period prevalence of WRULDs in these occupations. The main aim of the present study is to examine the prevalence of WRULDs at different durations of computer use, characterised as hours of computer use per day and at different levels of mouse use. Also, we aim to investigate the differences in these associations between men and women, and to examine whether a possible relationship between duration of computer use and WRULDs was explained by physical or psychosocial risk factors, such as prolonged static work position, wrist flexion and neck flexion, high work demands, low job control and low skill discretion.

Section snippets

Population and methods

This population was part of a company-based, nation-wide survey of 11,308 workers in The Netherlands. A two-step sampling procedure was used. Firstly, a representative sample of all companies were approached for participation in the study, except for companies with one employee and governmental and educational institutions. Secondly, if the company agreed to participate, the employees were asked to participate. Questionnaires were distributed to a part of the workers in each company. The number

Response

The response rate of the nation-wide survey was low: only 11,308 of the 45,000 questionnaires (25%) that were sent to the companies were returned. About half of this non-response was due to companies that initially agreed to participate but did not distribute the questionnaires to the workers after all. Of these 11,308 workers, 5403 office workers were selected for the present study.

Distribution of risk factors by occupation

In Table 2, the distributions of the duration of computer use, mouse use and physical risk factors are presented

Methodological limitations of the study

Although the large size of the study population originating from the general working population is a favourable aspect of the study, this type of study also has some methodological limitations, as has been pointed out by Gerr et al. (1996). The low response rate, the cross-sectional design of the study and the fact that only questionnaires were used for data collection may have affected the results. For instance, the low response rate may imply selective response: employees with health problems

Conclusion

From this study we may conclude that 4 h or more of self-reported computer use per day is associated with WRULDs in women, and that 6 h or more of computer use is associated with symptoms in men. Our data do not show that using a mouse 6–8 h/day is more harmful than using a keyboard 6–8 h/day. Future research should make use of the existing rest-break software, to register the number of mouse clicks, keys and breaks while using a computer, to be able to thoroughly investigate dose–response

References (26)

  • C. Jensen et al.

    Musculoskeletal symptoms and duration of computer and mouse use

    International Journal of Industrial Engineering

    (2002)
  • I. Kuorinka et al.

    Standardised nordic questionnaire for the analysis of musculoskeletal symptoms

    Applied Ergonomics

    (1987)
  • U. Bergqvist et al.

    Longitudinal study of VDT work and health

    International Journal of Human Computer Interaction

    (1992)
  • B. Bernard et al.

    Job task and psychosocial risk factors for work-related musuloskeletal disorders among newspaper employees

    Scandinavian Journal of Work, Environment, Health

    (1994)
  • R.F. Bettendorf

    Musculoskeletal disorders in the office workforce. Findings of the Office Ergonomics Research Committee (OERC)

    (1998)
  • A. Burdorf et al.

    In musculoskeletal epidemiology are we asking the unanswerable in questionnaires on physical load?

    Scandinavian Journal of Work, Environment, Health

    (1999)
  • J. Evans

    Women, men, VDU work and healtha questionnaire survey of British VDU operators

    Work & Stress

    (1987)
  • J. Faucett et al.

    VDT-related musculoskeletal symptomsinteractions between work posture and psychosocial factors

    American Journal of Industrial Medicine

    (1994)
  • J. Faucett et al.

    Musculoskeletal symptoms related to video display terminal use. An analysis of objective and subjective exposure estimates

    AAOHN Journal

    (1996)
  • F. Gerr et al.

    Methodological limitations in the study of video display terminal use and upper extremity musculoskeletal disorders

    American Journal of Industrial Medicine

    (1996)
  • T.R. Hales et al.

    Musculoskeletal disorders among visual display terminal users in a telecommunications company

    Ergonomics

    (1994)
  • Houtman, I.L.D., Kwantes, J.H., 1999. Background information on trends in occupational health. In: Houtman, I.L.D.,...
  • C. Jensen et al.

    Job demands, muscle activity and musculoskeletal symptoms in relation to work with the computer mouse

    Scandinavian Journal of Work, Environment, Health

    (1998)
  • Cited by (0)

    View full text