Musculoskeletal Disorders and the Workplace Low Back and Upper Extremities (2001) / Chapter Skim
Currently Skimming:
Occupational Stress
Occupational Stress
Pages 287-300
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 287... ...
Nonwork-related variables tend to be more commonly related to back than to upper extremity disorders. Given that the emphasis of this report is on work-related factors, this chapter reviews various models of occupational stress and discusses how exposure to stresses at work can impact the physiology of musculoskeletal pain in the spine and upper extremities.
|
From page 288... ...
This chapter reviews general models of occupational stress, biological correlates of stress exposure, selected theories related to how occupational stress might impact musculoskeletal disorders, and hypothesized pathways that may account for the relationship. GENERAL MODELS OF OCCUPATIONAL STRESS Several general models of occupational stress have emerged that define job stress and explain how certain aspects of work can contribute to the experience of stress.
|
From page 289... ...
The stress response is typically associated with systemic and localized physiological changes that are intended to reestablish a biological state of homeostasis (Selye, 1956~. It is postulated that recurrent or chronic exposure to a wide range of intrinsic or extrinsic stressors or demands repeatedly evokes a stress response, which, in turn, contributes to the etiology, exacerbation, and maintenance of a number of prevalent health problems
|
From page 290... ...
Specifically, cytokines or molecules released from various cells throughout the body following injury can interact not only with other cells within the immune system, altering their intracellular capabilities, but can also be directly affected by the brain's processing of the meaning of external events, such as stressors on the job and problems at home. While the complex biological processes involved in the stress response are just beginning to be revealed, current knowledge regarding the biological response to stress provides a foundation for understanding how psychological stressors may modulate activity within the nervous, endocrine, and immune systems, thereby exerting an effect on health.
|
From page 291... ...
One biobehavioral hypothesis for how exposure to work-related stressors may be associated with physiological processes involved in low back pain is that certain individuals possess a predisposition to respond to a stressor with increased paraspinal muscle activity, which may lead to ischemia, reflex muscle spasm, oxygen depletion, and the release of painproducing substances (e.g., histamine, substance P)
|
From page 292... ...
Upper Extremity Disorders Models Linking Occupational Stress to Work-Related Musculoskeletal Disorders In contrast to the back literature, over the past decade a number of work-specific models have been proposed to help explain how stress at
|
From page 293... ...
The balance theory of job design and stress provides a framework for examining the relationships and interactions among work organization, ergonomic exposure, job stress, and work-related upper extremity disorders. Smith and Carayon (1996)
|
From page 294... ...
294 _ ~ ~ in ~ o ~ w (n ~ ~ Q ~ ~ O - Q o O ~ C)
|
From page 295... ...
The workstyle model of job stress and musculoskeletal disorders (Feuerstein, 1996) was proposed to explain the relationship among job stress, ergonomic exposure, and work-related upper extremity disorders (illustrated in Figure 7.3~.
|
From page 296... ...
While these models have some components in common, each has a unique contribution, such as a focus on work systems, the integration of work demands and unpaid domestic workload, the labeling of or attributions for symptoms experienced in the process of work, and the potential impact of workstyle. Also, each of these models hypothesizes a psychophysiological substrate linking occupational stress to various health outcomes, in an effort to explain how job stress may affect work-related upper extremity disorders.
|
From page 297... ...
Spectral changes in forearm EMG, increased forearm tremor, and increased musculoskeletal discomfort have been observed in response to stress (Gomer et al., 1987~. In the absence of a quantifiable increase in work demands, the perception of an increase in work demands is sufficient to increase forearm muscular tension during task performance (Arndt, 1987~.
|
From page 298... ...
(1999) reported that catecholamine levels in male and female assembly workers who were given the opportunity to work in autonomous groups and to influence their work pace decreased more rapidly after work than did catecholamine levels in individuals who worked in the "traditional" work organization (with fixed workstations and short, repetitive work cycles)
|
From page 299... ...
Although the exact mechanism of injury differs from most work-related upper extremity disorders, it has recently been demonstrated that recovery from an oral puncture wound is significantly delayed following exposure to stress (Marucha, Kiecolt-Glaser, and Favagehi, 1998~. Production of interleukin-lp, a proinflammatory cytokine important in cell recruitment and activation of fibroblasts, was noted to decrease by 68 percent following exposure to a stressor.
|
From page 300... ...
These models need to be further validated. While the precise biological mechanisms through which these physiological responses to stress lead to musculoskeletal disorders have not been fully elucidated, work to date suggests that musculoskeletal, neuroendocrine, and immunological pathways may be prominent.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.