Work related psychosocial risks and musculoskeletal disorders: potential risk factors, causation and evaluation methods.

Musculo Skeletal Disorders (MSDs) are the focus of considerable attention and research in occupational health, which is in part due to high prevalence rates and associated costs. In the United States, the total cost associated with MSDs increased from $81 billion in 1986 to $215 billion in 2005 [3]. Epidemiological studies have repeatedly shown associations between work-related psychosocial factors and MSDs, and the role of psychosocial factors and stress in these disorders has received increased attention. Several reviews have reported associations between MSDs and work-related psychosocial factors such as high workload/demands, high perceived stress levels, low social support, low job control, low job satisfaction and monotonous work. Several theories have been proposed to explain the apparent relationship between stress and MSDs in the workplace from a biological perspective. These include the biopsychosocial model of job stress, the hyperventilation theory, the migraine theory, the muscle spindle theory and the Cinderella hypothesis. Within the literature, a vast array of questionnaires have been developed in an attempt to measure the psychosocial factors that occur within the workplace. This article presents a discussion of existing knowledge of the psychosocial risk factors potentially linked to MSDs and potential pathways to injury. A discussion of evaluation approaches used to estimate psychosocial risk exposures in workplaces is also presented.