Abstract
Work related musculoskeletal disorders are common among computer workers, especially in the neck/shoulder region and the upper extremities. The relation between physical and psychosocial work load and generation of pain is still unclear. In this paper we describe five models. According to the often addressed Cinderella hypothesis, the pain is due to an overuse of low threshold muscle fibres. In a series of studies including intramuscular electromyography from the trapezius muscle, we have found several motor units that were active throughout coarse arm movements, during prolonged computer work tasks, and in both voluntary and stress induced contractions. Furthermore we have seen that motor unit statistics varies significantly between repeated measurements in one individual, hence the method would be inappropriate for group comparisons. Finally, we discuss a model based on a general model, literature studies, and own research.
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Forsman, M., Thorn, S. (2007). Mechanisms for Work Related Disorders Among Computer Workers. In: Dainoff, M.J. (eds) Ergonomics and Health Aspects of Work with Computers. EHAWC 2007. Lecture Notes in Computer Science, vol 4566. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-73333-1_8
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DOI: https://doi.org/10.1007/978-3-540-73333-1_8
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