Social support, job strain and musculoskeletal pain among female health care personnel

Job strain and neck-shoulder symptoms: a prevalence study of women and men white-collar workers

BACKGROUND

Neck-shoulder symptoms are frequent among workers. Psychosocial factors at work have been associated with neck-shoulder symptoms, but few studies have examined job strain, the combined effect of high psychological demands (PD) and low decision latitude (DL).

AIMS

To examine the association between psychosocial factors at work and the prevalence of self-reported neck-shoulder symptoms among white-collar workers.

METHODS

In a cross-sectional study of 1543 white-collar workers, PD and DL at work were measured with Karasek's questionnaire. Prevalent cases were workers for whom neck-shoulder symptoms were present for >or=3 days during the previous 7 days and for whom pain intensity was greater than half the visual analogue scale. Gender and social support at work were evaluated as potential effect modifiers.

RESULTS

Workers exposed to high job strain had a higher prevalence of neck-shoulder symptoms [adjusted prevalence ratio (PR): 1.54, 95% confidence interval (CI): 1.00-2.37]. No modifying effect of gender was observed in this association. The effect of job strain was stronger in workers with low social support (adjusted PR: 1.84, 95% CI: 0.92-3.68). These associations tended to be stronger and/or more precise when using alternative exposures and case definition. Namely, a stronger job strain effect was observed when a tertile cut-off was used to classify exposure (adjusted PR: 2.47, 95% CI: 1.15-5.32).

CONCLUSION

These results suggest that primary prevention of neck-shoulder symptoms among white-collar workers should consider the exposure to job strain, especially when workers are exposed to low social support at work.

Musculoskeletal complaints among a group of Turkish nurses

The aim of the present study was to describe the prevalence and distribution of symptoms of musculoskeletal complaints among Turkish nurses who are practicing general nursing. The study population consisted of 120 nursing staff from four large general hospitals in Erzurum, Turkey. In every hospital six departments (surgery, medical, obstetric and gynecology, psychiatry, pediatric, and neurology) were selected. A Nordic standardized questionnaire described by Kuorinka et al. (1987) about complaints of the musculoskeletal system and a self-administered questionnaire involved information on the respondent's job and employment history, individual characteristics, physical and psychosocial risk factors at work, and general health status, were used by the researchers. Test data were analyzed for the difference between two population proportion and percentage. In the total population, 90% of all nurses reported at least one musculoskeletal complaint, 60% reported at least two, and 36% reported spells of three complaints in the past 6 months. Low back complaints were the most prevalent of musculoskeletal complaints, reported by 69% of the nurses. Neck complaints were less prevalent than shoulder (46% and 54%, respectively). Nurses with back complaint more often reported neck (28%) and shoulder (34%) complaints. Chronic low back, neck, and shoulder complaints were experienced by 41%, 25%, and 33% nurses, respectively. On the other hand, chronic complaints showed a correlation with working departments. The nurses working in surgery and obstetric and gynecology departments have more chronic complaints than the nurses working in other department (p<.05). The article's findings do not differ from those of other countries. Despite its limitations, this study points to the importance of perceived worked-related physical demands in relation to reported neck, shoulder, and back musculoskeletal complaints in Turkish nurses. But, further inquiries are needed to identify other physical exposures that may be related to musculoskeletal complaints.

Impact of occupational stress and other psychosocial factors on musculoskeletal pain among Chinese offshore oil installation workers

AIMS

To explore the relation between psychosocial factors and musculoskeletal pain in Chinese offshore oil installation workers.

METHODS

Half of all offshore workers (being a representative sample) in a Chinese oil company were invited to complete a self-administered questionnaire providing information on sociodemographic characteristics, occupational stressors, type A behaviour, social support, coping style, health related behaviour, past injuries, and musculoskeletal pain. Factor analysis was used to identify the sources of occupational stress and the domains of type A behaviour and coping style. Logistic regression analyses were used to study the relations between psychosocial factors and musculoskeletal pain in each body region.

RESULTS

The prevalence of musculoskeletal pain over the previous 12 months varied between 7.5% for elbow pain and 32% for low back pain; 56% workers had at least one complaint. Significant associations were found between various psychosocial factors and musculoskeletal pain in different body regions after adjusting for potential confounding factors. Occupational stressors, in particular stress from safety, physical environment, and ergonomics, were important predictors of musculoskeletal pain, as was coping by eating behaviour.

CONCLUSIONS

These observations supported the widely accepted biopsychosocial model of musculoskeletal disorders and suggested that in future studies of work related musculoskeletal disorders, psychosocial factors must be given due consideration.

Work factors as predictors of intense or disabling low back pain; a prospective study of nurses' aides

AIMS

To identify the work factors that predict intense low back pain (LBP) and LBP related sick leaves in nurses' aides.

METHODS

The sample comprised 4266 randomly selected Norwegian nurses' aides, not bothered or only a little bothered by LBP during the previous three months, and not on sick leave when completing a mailed questionnaire in 1999. Of these, 3808 (89.3%) completed a second questionnaire 3 months later and 3651 (85.6%) completed a third questionnaire 15 months later. Intensity of low back symptoms and certified sick leaves attributed to LBP during the observation period were assessed by self reports at the follow ups.

RESULTS

After adjustments for LBP during the three months prior to baseline, baseline health complaints, demographic and familial factors, and a series of physical, psychological, and social work factors, logistic regression analyses revealed the following associations: intense low back symptoms were predicted by frequent positioning of patients in bed, perceived lack of support from immediate superior, and perceived lack of pleasant and relaxing culture in the work unit. LBP related sick leaves were predicted by frequent handling of heavy objects, medium level of work demands, perceived lack of supportive and encouraging culture in the work unit, working night shifts, and working in a nursing home. Long term LBP related sick leaves were associated with changes of work or work tasks during the observation period that resulted in a perceived reduction of support and encouragement at work.

CONCLUSIONS

Not only frequent mechanical exposures, but also organisational, psychological, and social work factors, such as night shift work, perceived lack of support from superior, and perceived lack of a pleasant and relaxing or supporting and encouraging culture in the work unit, are associated with an increased risk of intense low back symptoms and LBP related sick leaves in nurses' aides.

Psychosocial risk factors for musculoskeletal symptoms among women working in geriatric care

BACKGROUND

Nursing is a stressful, physically demanding occupation and a rush setting for musculoskeletal problems. The aim of this study is to explore the extent of the association between psychosocial work characteristics and musculoskeletal symptoms among women working in geriatric care.

METHODS

The participants were female employees of all geriatric nursing homes and geriatric hospital wards in Iceland having a staff of 10 or more. A total of 1,886 questionnaires were distributed. The response rate was 80%.

RESULTS

Finding the job mentally difficult, mental exhaustion after one's shift, dissatisfaction with supervisors or the flow of information, insufficient influence at work, dissatisfaction with the hierarchy, intense time pressure, lack of solidarity, dissatisfaction with the job, harassment, violence or threats at work; all of the aforementioned gave crude odds ratios (OR) two or above for one or more musculoskeletal symptoms. Mental exhaustion and harassment, violence, and threats were the factors connected with symptoms from all the body regions studied.

CONCLUSIONS

The extent of the association of work-related psychosocial factors and musculoskeletal symptoms among the geriatric female nursing staff is substantial and needs to be taken into account by occupational health services and others involved in preventive work. Am. J. Ind. Med. 44:679-684, 2003.

Risk factors for incident neck and shoulder pain in hospital nurses

AIM

To assess the incidence and risk factors for neck and shoulder pain in nurses.

METHODS

A longitudinal study of neck and shoulder pain was carried out in female nurses at two hospitals in England. Personal and occupational risk factors were assessed at baseline. The self reported incidence of symptoms in the neck and shoulder region was ascertained at three-monthly intervals over two years. A Cox regression model was used to estimate hazard ratios (HRs) for incident neck/shoulder pain during follow up in nurses who had been pain free for at least one month at baseline.

RESULTS

The baseline response rate was 56%. Of 903 women who were pain free at baseline, 587 (65%) completed at least one follow up while still in the same job. During an average of 13 months, 34% of these (202 women) reported at least one episode of neck/shoulder pain. The strongest predictor of pain in the neck/shoulder was previous history of the symptom (HRs up to 3.3). For physical exposures at work, the highest risks (HRs up to 1.7) were associated with specific patient handling tasks that involved reaching, pushing, and pulling. Nurses who reported low mood or stress at baseline were more likely to develop neck/shoulder pain later (HR 1.5). Workplace psychosocial factors (including job demands, satisfaction, and control) were not associated with incident neck/shoulder symptoms.

CONCLUSIONS

Neck/shoulder pain is common among hospital nurses, and patient handling tasks that involve reaching and pulling are the most important target for risk reduction strategies.

To seek or not to seek? Care-seeking behaviour among people with low-back pain

AIM

The present study sought to identify potential differences between subjects who seek care for their low-back pain problems and those who do not with respect to pain intensity, grade of disability, physical or psychosocial working conditions, individual physical and physiological factors, and lifestyle factors.

MATERIAL AND METHODS

The study population was obtained from a population-based, case-referent study, the MUSIC-Norrtälje study. All persons with low-back pain among cases as well as "referents" were compared according to care-seeking behaviour. In all 727 cases with low-back pain who had sought care by any of 75 caregivers in the region, including all physicians and physiotherapists as well as chiropractors, osteopaths, and homeopaths, 721 referents with low-back pain who did not seek care participated. All participants underwent a clinical examination, and filled in a questionnaire about personal and occupational data, pain and disability, pain history, psychosomatic complaints, and present psychosocial situation.

RESULTS

High disability and high pain intensity were strongly related to care seeking among men and women with low-back pain. The odds ratios for high disability were 7.4 (CI 5.0 - 11.0) for women and 4.9 (CI 3.3 - 7.1) for men respectively. The odds ratios for high pain intensity were 3.7 (CI 2.2 - 6.0) for women and 1.7 (CI 1.1 - 2.8) for men. A more strained economic situation and use of passive coping strategies significantly increased the probability of women not seeking care. Neither previous pain history, high physical workload, nor jobstrain, poor job satisfaction, or life style factors (high body weight, smoking, and exercise) or psychosomatic complaints affected care-seeking behaviour.

CONCLUSIONS

The most decisive factors for seeking care were disability and pain. However, numerous individuals with low disability and low pain intensity also seek care for their pain problems. Better information and advice on the common course of low-back pain may make those individuals less frightened of their pain and, as a result, reduce the consumption of care and social costs for society. The majority of people seek care for pain without wanting a medical prescription. The fact that economic factors seemed to be of importance indicates that costs for healthcare must be kept low if the goal is to give healthcare on equal terms for all.

Personality traits predict self-referral of young male adults with musculoskeletal complaints to a general practitioner

OBJECTIVE

To investigate the effects of personality traits on self-referral to a general practitioner (GP).

METHODS

217 male soldiers who underwent advanced training course filled the Eysenck Personality Questionnaire-Revised (EPQ-R) and the Perceived Stress Scale and were followed up for a period of 14 weeks. Every soldier who self-referred to the clinic was physically examined by a GP. The major complaint and the GP's diagnosis were documented.

RESULTS

106 of the 217 soldiers self-referred. Self-referred soldiers had significantly (P=.02) higher levels of extraversion than soldiers who did not. Specifically, higher levels of extraversion were evident among soldiers who self-referred with musculoskeletal complaints (P<.05). No significant difference in stress levels was found between soldiers who self-referred and those who did not.

CONCLUSIONS

These findings underscore the association between extraversion and musculoskeletal complaints among young adult males and suggest that psychological variables should be taken under consideration in the prevention and treatment of orthopedic problems.

The changing organization of work and the safety and health of working people: a commentary

Recent trends in the organization of work may affect worker health through a variety of pathways--by increasing the risk of stress-related illnesses, such as cardiovascular disease, musculoskeletal disorders, and psychological disorders, by increasing exposure to hazardous substances and violence on the job, or by affecting occupational health services and training programs. Much remains to be learned about the nature of changes in work organization, and how they affect worker health and safety. While available evidence is limited, such evidence suggests that recent trends in work organization may be increasing the risk of occupational illnesses. In a groundbreaking publication, the National Institute for Occupational Safety and Health has provided a concise summary of available knowledge and a detailed agenda for research and development.

The impact of mental processing and pacing on spine loading: 2002 Volvo Award in biomechanics

STUDY DESIGN

The impact of various levels of mental processing and pacing (during lifting) on spine loading was monitored under laboratory conditions.

OBJECTIVES

To explore how mental demands and pacing influence the biomechanical response and subsequent spine loading and, to determine whether individual characteristics have a modifying role in the responses.

SUMMARY OF BACKGROUND DATA

Modern work often requires rapid physical exertions along with demands of mental processing (both psychosocial stressors). While the effect of physical workplace factors on spine loading has been widely documented, few studies have investigated the impact that interaction of psychosocial factors and individual factors has on spine loads.

METHODS

For this study, 60 subjects lifted boxes while completing two types of mental processing tasks: 1) series tasks with decisions occurring before the act of lifting, and 2) simultaneous tasks with decisions occurring concurrently with the lift. For both of these mental processing conditions, two intensities of mental load were evaluated: simple and complex. Task pacing was also adjusted under slow and fast conditions. Finally, individual characteristics (personality and gender) were evaluated as potential modifiers. An electromyographically assisted model evaluated the three-dimensional spine loads under the experimental conditions.

RESULTS

Simultaneous mental processing had the largest impact on the spine loads, with the complex intensity resulting in increases of 160 N with lateral shear, 80 N with anteroposterior shear, and 700 N with compression. Increased task pace produced greater lateral shear (by 20 N), anteroposterior shear (by 60 N), and compression loads (by 410 N). Gender and personality also influenced loadings by as much as 17%.

CONCLUSIONS

Mental processing stress acted as a catalyst for the biomechanical responses, leading to intensified spine loading. Mental stress appeared to occur as a function of time pressures on task performance and resulted in less controlled movements and increases in trunk muscle coactivation. These adjustments significantly increased spine loading. These results suggest a potential mechanism for the increase in low back pain risk resulting from psychosocial stress caused by modern work demands.

Workplace empowerment, collaborative work relationships, and job strain in nurse practitioners

PURPOSE

To test a theoretical model linking nurse practitioners' (NPs) perceptions of workplace empowerment, collaboration with physicians and managers, and job strain.

DATA SOURCES

A predictive, nonexperimental design was used to test a model in a sample of 63 acute care NPs and 54 primary care NPs working in Ontario, Canada. The Conditions of Work Effectiveness Questionnaire, the Collaborative Behaviour Scale--Parts A (physicians) and B (managers), and the Job Content Questionnaire were used to measure the major study variables.

CONCLUSIONS

The results of this study support the proposition that the extent to which NPs have access to information, support, resources, and opportunities in their work environment has an impact on the extent of collaboration with physicians and managers, and ultimately, the degree of job strain experienced in the work setting. Primary care NPs have significantly higher levels of workplace empowerment, collaboration with managers, and lower levels of job strain than acute care NPs.

IMPLICATIONS

These findings will benefit NPs and nursing leaders in their efforts to create empowering work environments that enable NPs to provide excellent quality patient care and achieve organizational outcomes.

Sleep disturbances, work stress and work hours: a cross-sectional study

OBJECTIVE

The study examined the multivariate relationship between disturbed sleep and different work-related and background/life style factors.

METHODS

5720 healthy employed men and women living in the greater Stockholm area participated. A factor analysis of eight items provided one main factor: "disturbed sleep." The data were analyzed using a multiple logistic regression analysis against the index disturbed sleep as well as the separate items "not well rested" and "difficulties awakening."

RESULTS

The results showed that high work demands [odds ratio (OR) = 2.15] and physical effort at work (OR = 1.94) are risk indicators for disturbed sleep, while high social support is associated with reduced risk (OR = 0.44). In addition, higher age (45+), female gender, a high body mass index (BMI) and lack of exercise are background/life style risk indicators. Introducing into the model an item representing inability to stop thinking about work during free time yielded the highest OR (3.20) and forced work demands out of the regression. With regard to not feeling well rested, the same significant predictors, except physical effort, were obtained, as well as for having night work and being married. In addition, the age effect was reversed--high age predicted reduced risk of not feeling well rested. Difficulties awakening was predicted by high work demands, low social support, being male, low age and smoking. It is notable that, whereas subjective sleep quality decreased with age, the difficulties awakening and feelings of not being well rested after sleep increased with age.

CONCLUSION

It was concluded that stress and the social situation at work are strongly linked to disturbed sleep and impaired awakening, that gender and, even more so, age may modify this and that the inability to stop worrying about work during free time may be an important link in the relation between stress and sleep.

[Validity of the Nordic Musculoskeletal Questionnaire as morbidity measurement tool]

OBJECTIVES

To validate the Portuguese version of the Nordic Musculoskeletal Questionnaire (NMQ), and to evaluate the relationship between musculoskeletal morbidity and demographic, occupational and behavior variables.

METHODS

Ninety government bank employees were interviewed using the Portuguese version of NMQ in Brasilia, Brazil, in 1999. The respondents' answers were compared to clinical data found in their medical records. Descriptive and associative variable analyses were carried out. Comparative statistical analysis was performed using Student t-test and Pearson's test was applied for correlational analysis.

RESULTS

The results revealed an 86% agreement rate between symptoms reported in the NMQ and the respondent's clinical history. There were found differences in symptoms prevalence for the variables gender, occupation and physical activity. Women showed a higher severity average of symptoms for almost all body anatomical regions; managers reported greater severity of symptoms in the lumbar area than clerks; physical activity was associated to the lowest severity of symptoms in upper extremities.

CONCLUSIONS

The results show that the Portuguese NMQ version includes a good validity indicator and is satisfactory as a musculoskeletal morbidity measurement tool. However, there is a need of (1) more items to measure the severity of symptoms; and (2) changes in scale layout in order to make it more easily understandable and less prone to avoidable missing data.

Are psychosocial factors, risk factors for symptoms and signs of the shoulder, elbow, or hand/wrist?: A review of the epidemiological literature

BACKGROUND

In 1993, an extensive review on the role of psychosocial factors in the development of musculoskeletal problems was published by Bongers et al (1993). Since then, additional reviews on this topic have been published; however, none of these focussed on upper limb problems.

METHODS

In this systematic review, the methodological quality of all studies was assessed and levels of evidence were apriori defined.

RESULTS

The large majority of the studies reported an association between at least one work-related psychosocial factor and adverse upper extremity symptoms or signs. High-perceived job stress was consistently associated with all upper extremity problems (UEP) in high and lower quality studies. Although not often studied, non-work-related stress was also consistently associated with UEP. In addition, there was some evidence for a relationship between high job demands and UEP, although the results did not meet the pre-set criterion for consistency.

CONCLUSIONS

High job stress and non-work-related stress reactions are consistently associated with UEP. In addition, high job demands is also in most studies associated with these disorders. Firm conclusions on the role of these factors in the etiology of UEP are not possible due to the cross-sectional nature of most studies.

The activation of mechanisms linking judgements of work design and management with musculoskeletal pain

The report of work-related musculoskeletal pain may be related to worker evaluations of the design and management of work through two mechanisms: one biomechanical and the other stress-related. This study of engineering workers (n = 204) explored the validity of these mechanisms using sequential logistic regression. Analyses suggested that workers' ratings of the adequacy of the design and management of their work were related to their report of work-related musculoskeletal pain. However, the mechanisms appeared to be activated in certain conditions. The reporting of pain in the upper body was both biomechanically- and stress-related, whereas that in the lower body was only biomechanically-related. It is argued that the mechanism activated appeared to be determined by the anatomical location of the pain, and probably the variance shared between the different aspects of work design and management, on the one hand, and the mechanical load of the job, on the other.

Hospitalizations among female home-helpers in Denmark, 1981-1997

BACKGROUND

Occupational health problems among home-helpers have been reported in a series of studies, and the need for intervention has been pointed out. To facilitate decisions regarding interventions and to establish baseline values for future evaluation of preventive efforts, the present study aimed to elucidate the disease pattern among female home-helpers in Denmark.

METHODS

Cohorts of all 20-59-year-old Danish female home-helpers in the years 1981, 1986, 1991, and 1994 were formed, to calculate age standardized hospitalization ratios (SHR) and time trends (1981-1997) for a large variety of diagnostic aggregations.

RESULTS

Significantly high SHRs were found for injuries, infectious and parasitic diseases, and for diseases of the nervous system, circulatory system, the respiratory organs, digestive system, and the musculoskeletal system. When adjusting for social group the SHRs for varicose veins, ischemic heart diseases (IHD), and musculoskeletal disorders were still significantly high while the SHR for malignant neoplasm of respiratory organs became significantly low. The time trends revealed increased relative risks for IHD and asthma, and a decreasing relative risk for duodenal ulcer.

CONCLUSIONS

Employment in the Danish home-help sector is associated with an elevated hospitalization risk due to many work-related diseases.

Job strain and self-reported health among working women and men: an analysis of the 1994/5 Canadian National Population Health Survey

This paper explores the associations, for working women and men, of high strain jobs with self-rated health in the 1994/95 Canadian National Population Health Survey (NPHS). NPHS data were obtained on men (n = 4230) and women (n = 4043), aged 18-64 who answered an abbreviated version oF the job content questionnaire (JCQ). Using the upper and lower tertiles of psychological demands and decision latitude as cut points we classified workers into high strain and other jobs. Self-rated health was the outcome. We used polytomous logistic regression analyses and controlled for potential personal and home confounders; two risk parameters were estimated: for the odds of reporting poor/fair and good health both vs. very good/excellent health. High strain work was reported by 11% of women and 9% of men. After adjusting for potential confounders, high job strain was consistently associated with worse self-rated health in both models for each gender.

High quantitative job demands and low coworker support as risk factors for neck pain: results of a prospective cohort study

STUDY DESIGN

A 3-year prospective cohort study among 1334 workers was conducted.

OBJECTIVE

To determine whether the work-related psychosocial factors of quantitative job demands, conflicting job demands, skill discretion, decision authority, supervisor support, coworker support, and job security are risk factors for neck pain.

SUMMARY OF BACKGROUND DATA

Among the various risk factors for neck pain, work-related psychosocial factors play a major role. Previous studies on risk factors for neck pain often had a cross-sectional design, and did not take both physical and psychosocial factors into account.

METHODS

At baseline, data on work-related psychosocial factors were collected by means of a questionnaire. During the 3-year follow-up period, data on the occurrence of neck pain were collected by means of postal questionnaires. Individuals without neck pain at baseline were selected for the analyses. Cox regression analysis was applied to examine the relation between the work-related psychosocial factors and the cumulative incidence of neck pain. Adjustments were made for various physical factors and individual characteristics.

RESULTS

The analysis included 977 patients. Altogether, 141 workers (14.4%) reported that they had experienced neck pain at least once during the 3-year follow-up period. The relation of neck pain to high quantitative job demands (relative risk [RR], 2.14; 95% confidence interval [CI], 1.28-3.58) and low coworker support (RR, 2.43; 95% CI, 1.11-5.29) was statistically significant. An increased risk was found for low decision authority in relation to neck pain (RR, 1.60; 95% CI, 0.74-3.45), but this relation was not statistically significant.

CONCLUSIONS

High quantitative job demands and low coworker support are independent risk factors for neck pain. There are indications that another risk factor for neck pain is low decision authority.

Biomechanical and psychosocial risk factors for low back pain at work

OBJECTIVES

This study determined whether the physical and psychosocial demands of work are associated with low back pain.

METHODS

A case-control approach was used. Case subjects (n = 137) reported a new episode of low back pain to their employer, a large automobile manufacturing complex. Control subjects were randomly selected from the study base as cases accrued (n = 179) or were matched to cases by exact job (n = 65). Individual, clinical, and psychosocial variables were assessed by interview. Physical demands were assessed with direct workplace measurements of subjects at their usual jobs. The analysis used multiple logistic regression adjusted for individual characteristics.

RESULTS

Self-reported risk factors included a physically demanding job, a poor workplace social environment, inconsistency between job and education level, better job satisfaction, and better coworker support. Low job control showed a borderline association. Physical-measure risk factors included peak lumbar shear force, peak load handled, and cumulative lumbar disc compression. Low body mass index and prior low back pain compensation claims were the only significant individual characteristics.

CONCLUSIONS

This study identified specific physical and psychosocial demands of work as independent risk factors for low back pain.

Self-reported musculoskeletal disorders among visiting and office home care workers

This paper examines the associations between self-reported musculoskeletal disorders (MSDs) and work factors and injuries among home care workers. Based on 99 focus group participants and 892 survey respondents, results show a high level of MSDs among both visiting and office home care workers. While visiting home care workers tend to feel pain in the back, office workers tend to report pain in the neck and shoulder. Hazards in clients' homes, injuries moving clients and stress are associated with self-reported MSDs for visiting home care workers. Repetitive tasks and stress are associated with self-reported MSDs for office home care workers. Age and months in the profession have no affect on self-reported MSDs.

Shoulder and neck complaints in customer relations: individual risk factors and perceived exposures at work

Perceived psychosocial and biomechanical exposures, individual factors and pain in the shoulder and neck were recorded in two groups of female service workers (healthcare and shopping centre workers). The jobs investigated were characterized by 'much' direct human relations, 'little' sitting and 'much' standing, and were light work by physiological or biomechanical criteria but potentially psychosocially demanding. A screening survey (n = 400 females) was the basis for the selected sample (n = 66 females), which was the object of the main investigation of this study. Reliability of the questionnaires was tested in a separate group of female healthcare workers (n = 29). Heart rate recordings through the work day estimated workload. There was a high prevalence of shoulder and neck pain (> 50%) for both work groups. In the two populations it proved difficult to explain shoulder and neck pain by reported physical and psychosocial exposures or individual factors, except by the variable 'perceived general tension', which clearly differentiated workers with and without pain. The findings in this study indicated, first, that perceived general tension might be an independent risk factor for muscle pain and, second, that this might be related to personality factors. However, this putative relationship must be verified in a longitudinal study. As no variable describing exposures in the working environment was associated with shoulder and neck pain, the question is posed whether such complaints can be considered work-related. Alternatively, the variables used to describe mechanical and psychosocial exposures in this study may have low specificity in characterizing work-related risk factors for service workers with customer relations.

Psychosocial risk factors for neck pain: a systematic review

BACKGROUND

Neck pain, which is assumed to be a multifactorial disease, is a major problem in modern society.

METHODS

To identify the most important psychosocial risk factors for neck pain, a systematic review of the literature was carried out. The methodological quality of all studies in the review was assessed. Four levels of evidence were defined to assess the strength of evidence for potential risk factors for neck pain (strong, moderate, some or inconclusive evidence).

RESULTS

Some evidence was found for a positive relationship between neck pain and high quantitative job demands, low social (coworker) support, low job control, high and low skill discretion and low job satisfaction. Inconclusive evidence was found for high job strain, low supervisor support, conflicts at work, low job security, and limited rest break opportunities.

CONCLUSIONS

The procedure of the assessment of the methodological quality and the rating system applied to distinguish between high- and low-score studies, had a considerable influence on the level of evidence, indicating that changes in this procedure may have a major impact on the overall conclusions of this review.

Endocrine and immunologic parameters indicative of 6-month prognosis after the onset of low back pain or neck/shoulder pain

STUDY DESIGN

Prospective study.

OBJECTIVES

To evaluate the prognosis of spine disease by investigating biologic parameters reflecting different physiologic or psychophysiological systems in men and women with acute onset of low back or neck/shoulder complaints.

SUMMARY OF BACKGROUND DATA

Psychosocial factors may be of importance to the etiology and prognosis of musculoskeletal disorders. The possible mechanisms, however, remain unclear. Stress-induced long-lasting energy mobilization resulting in inhibited anabolism has been discussed. Using a theoretical framework within stress physiology, such psychophysiological processes were recorded by measures of substances representing the anabolic, catabolic, immunologic, and opioid systems.

METHODS

The study comprised 67 working men and women 21 to 59 years of age seeking care by any caregiver for acute low back and/or neck/shoulder pain. Blood samples were taken and analyzed for 3 methyl 5hydroxy phenylethylene glycol (MHPG, reflecting sympathoadrenomedullary activity), DHEA-s (anabolism), immunoglobulin E, interleukin 6 (immune activity), and beta-endorphin (pain regulation). The participants were followed up for 6 months after the blood samples had been drawn.

RESULTS

In women, low MHPG, low DHEA-s, and low beta-endorphin predicted persistent disability due to low back complaints. Few significant findings were made for self-reported pain, for neck/shoulder complaints, and for men.

CONCLUSION

Disturbances of the regulation of certain biologic parameters might be indicators of a prolonged course of low back disease in women. Prospective studies are necessary to enable causal conclusions.

The influence of psychosocial stress, gender, and personality on mechanical loading of the lumbar spine

STUDY DESIGN

The effects of psychosocial stress on muscle activity and spinal loading were evaluated in a laboratory setting.

OBJECTIVE

To evaluate the influence of psychosocial stress, gender, and personality traits on the functioning of the biomechanical system and subsequent spine loading.

SUMMARY OF BACKGROUND DATA

Physical, psychosocial, and individual factors all have been identified as potential causal factors of low back disorders. How these factors interact to alter the loading of the spine has not been investigated.

METHODS

Twenty-five subjects performed sagittally symmetric lifts under stressful and nonstressful conditions. Trunk muscle activity, kinematics, and kinetics were used to evaluate three-dimensional spine loading using an electromyographic-assisted biomechanical model. A personality inventory characterized the subject's personality traits. Anxiety inventories and blood pressure confirmed reactions to stress.

RESULTS

Psychosocial stress increased spine compression and lateral shear, but not in all subjects. Differences in muscle coactivation accounted for these stress reactions. Gender also influenced spine loading; Women's anterior-posterior shear forces increased in response to stress, whereas men's decreased. Certain personality traits were associated with increased spine loading compared with those with an opposing personality trait and explained loading differences between subjects.

CONCLUSIONS

A potential pathway between psychosocial stress and spine loading has been identified that may explain how psychosocial stress increases risk of low back disorders. Psychosocially stressful environments solicited more of a coactivity response in people with certain personality traits, making them more susceptible to spine loading increases and suspected low back disorder risk.

The relationship between psychosocial work characteristics and low back pain: underlying methodological issues

OBJECTIVE

To evaluate the current epidemiological evidence linking psychosocial work characteristics with low back pain.

BACKGROUND

Psychosocial work characteristics have been widely evaluated as potential risk factors for low back injury. However, studies with different study populations and using various types of measures have had conflicting results.

METHODS

This review is the most extensive to date, reviewing 66 articles that have provided empirical evidence about the relationship between psychosocial work characteristics and initial reporting of lower back pain. The studies are reviewed with an emphasis on certain methodological issues: controlling for potential confounding; timing of the data collection; and measurement of the exposures and outcomes.

RESULTS

The results of this review suggest that controlling for potential confounding from occupational biomechanical demands had a large influence on the associations found between psychosocial work characteristics and lower back pain. In addition, the use of accurate and reliable measures for the occupational exposures (biomechanical and psychosocial) and the lower back pain outcomes appears to influence the strength of the associations found between psychosocial work characteristics and lower back pain.

CONCLUSION

Given the methodological concerns discussed in this review, it is difficult to draw strong causal inferences from this literature. However, it does appear that psychosocial characteristics are related to some lower back pain outcomes, and that employees' reactions to psychosocial work characteristics (e.g., job dissatisfaction and job stress) are more consistently related to lower back pain than are the psychosocial work characteristics themselves (e.g., work overload, lack of influence over work, quality of relationships with coworkers).

RELEVANCE

This review attempts to identify and address methodological issues in the literature evaluating the relationship between psychosocial work characteristics and lower back pain. Implications for future research are presented.

Individual and occupational determinants of low back pain according to various definitions of low back pain

OBJECTIVES

To test associations between non-specific low back pain and several risk factors when definitions of low back pain vary.

DESIGN/SETTING/PARTICIPANTS

A cross sectional study was set up in 1991, 725 workers from four occupational sectors answered a self administrated questionnaire including the Nordic questionnaire and questions about intensity of pain and individual and occupational factors.

MAIN RESULTS

Prevalence of low back pain varied from 8% to 45% according to the definition used. Psychosomatic problems, bending or carrying loads were often associated to low back pain, whereas other risk factors were related to some specific dimensions of the disorder.

CONCLUSIONS

Risk factors of low back pain vary with the definition. This could explain inconsistencies found in literature reviews. To be able to compare data, it seems important to be precise what definition is used and to use comparable questionnaires.

To what extent do current and past physical and psychosocial occupational factors explain care-seeking for low back pain in a working population? Results from the Musculoskeletal Intervention Center-Norrtälje Study

STUDY DESIGN

A population-based case referent study.

OBJECTIVES

To determine whether current and past physical and psychosocial occupational factors are associated with care-seeking for low back pain in working men and women.

SUMMARY OF BACKGROUND DATA

The importance of physical and psychosocial workloads as causal factors of low back pain has mostly been investigated in special occupational groups and with a cross-sectional design, which makes generalizability and interpretations more difficult.

METHODS

The study comprised 2118 working men and women 20 to 59 years old (695 cases, and 1423 referents). Cases were defined as persons seeking care by any caregiver for low back pain. The exposure assessments were made through questionnaires and interviews about current and past physical and psychosocial loads during work and leisure time.

RESULTS

In a logistic regression analysis, physical load from forward bending in men (RR = 1.8) and high physical load, in general, in women (RR = 2.0) showed increased relative risks. Psychosocial factors alone seemed to be of less importance in women, but "poor job satisfaction" and "mostly routine work without possibilities of learning" increased the risk in men. Combined current and past exposures further increased the risks. A combination of high physical and psychosocial loads increased the risk substantially, but few were exposed to such loads. Adjustment for lifestyle and other loads outside work did not change the results.

CONCLUSION

Current and past physical and psychosocial occupational factors, both separately and combined, seem to be gender-specific, and to have a moderate impact on care-seeking for low back pain in a general working population.

Stress from working conditions among home care personnel with musculoskeletal symptoms

A large proportion of the working population experiences musculoskeletal symptoms, which affect the individual's quality of life. Neck/shoulder and/or low back complaints are common among home care personnel. This occupational sector is characterized by high physical and psychosocial demands and the staff is typically female. The aim of this qualitative study was to gain a deeper understanding of those factors in the work environment of home care personnel that the individuals perceive as demanding and problematic. Eight employees in the home care service were interviewed in depth. Each interview was transcribed and Grounded Theory was applied. Stress, related to demanding physical and psychosocial working conditions, emerged as the core variable that probably contributed to the development and maintenance of musculoskeletal symptoms. Financial cut-backs at the municipality was seen as a cause of the demanding working conditions. In future studies it is important to evaluate prevention programmes focused upon coping strategies against stress.

Muscle activity as a releasing factor for pain in the shoulder and neck

In this review, the evidence for trapezius muscle activity as a releasing factor for shoulder and neck pain is considered, mainly on the basis of studies in our laboratory. Two lines of evidence are produced, (i) vocational studies in an occupational setting, where muscle activity pattern is recorded by surface EMG and a clinical examination of the shoulder region of the subjects performed; and (ii) laboratory studies where muscle activity patterns and pain development are recorded in an experimental situation with mental stress and minimal physical activity. The vocational studies demonstrate pain development in the shoulder and neck despite very low muscle activity recorded, making it very difficult to assume muscular involvement for all cases with such complaints. However, the hypothesis of pain development through overexertion of a subpopulation of low-threshold motor units also makes it difficult to draw a firm negative conclusion. The laboratory experiments, on the other hand, show that trapezius activity patterns in response to stress have many features that would be expected if muscle activation induces pain symptoms. It is further noted that the trapezius is the only muscle with activity patterns that show these features. Possibly, we observe the effects of parallel physiological phenomena, e.g., a systemic autonomic activation that induces pain symptoms and also facilitates the motor response of some muscles. Evidence of autonomic activation of trapezius is presented by the observation of low-level, rhythmic EMG activity during sleep. However, this is not firm evidence for the above hypothesis, which at present best serves as a basis for further experimentation.

Work organization, job stress, and work-related musculoskeletal disorders

Recent studies indicate potential links among work organization, job stress, and work-related musculoskeletal disorders (WRMDs). In this paper we propose several pathways for a theoretical relationship between job stress and WRMDs. These pathways highlight the physiological, psychological, and behavioral reactions to stress that can affect WRMDs directly and indirectly. One model stipulates that psychosocial work factors (e.g., work pressure, lack of control), which can cause stress, might also influence or be related to ergonomic factors such as force, repetition, and posture that have been identified as risk factors for WRMDs. In order to fully understand the etiology of WRMDs, it is important to examine both physical ergonomic and psychosocial work factors simultaneously. Smith and Carayon-Sainfort (1989) have proposed a model of the work system for stress management that provides a useful framework for conceptualizing the work-related factors that contribute to WRMDs. Practical applications of this research include practitioners taking into account psychosocial work factors and job stress in their efforts to reduce and control WRMDs.

Work-related musculoskeletal complaints in sonologists

The prevalence of musculoskeletal complaints of the hand and wrist, and the neck and back, in physicians who operate sonography equipment was evaluated, and associations between these complaints and various work-related and personal variables were studied. A questionnaire survey was distributed among physician sonographers (sonologists) in Italy. The relationship between work habits and musculoskeletal complaints was analyzed by logistic regression models adjusted for gender, age, and duration of work with ultrasound. A total of 2041 physician sonographers completed the questionnaire. It was found that a large proportion of the subjects regularly had work-related complaints, such as neck and back pain (NBP) (18.5%) or hand and wrist cumulative trauma disorder (HWD) (5.3%). Roughly 80% of the sonographers were currently affected, or had been affected in the past, by one or more work-related symptoms. Various work-related factors appeared to be related to musculoskeletal syndromes. The average time spent for each examination was related both to NBP and HWD. Discomfort for transducer design was the best predictor of HWD, whereas a comfortable chair and correct position of the body protected from the onset of NBP. These results support the role of ergonomic factors in the pathogenesis of both NBP and HWD in sonographers.

Back injury in municipal workers: a case-control study

OBJECTIVES

The purpose of this study was to identify factors associated with acute low back injury among municipal employees of a large city.

METHODS

For each of 200 injured case patients, 2 coworker controls were randomly selected, the first matched on gender, job, and department and the second matched on gender and job classification. In-person interviews were conducted to collect data on demographics, work history, work characteristics, work injuries, back pain, psychosocial and work organization, health behaviors, and anthropometric and ergonomic factors related to the job. Psychosocial work organization variables were examined with factor analysis techniques; an aggregate value for job strain was entered into the final model. Risk factors were examined via multivariate logistic regression techniques.

RESULTS

High job strain was the most important factor affecting back injury (odds ratio [OR] = 2.12, 95% confidence interval [CI] = 1.28, 3.52), and it showed a significant dose-response effect. Body mass index (OR = 1.54, 95% CI = 1.08, 2.18) and a work movement index (twisting, extended reaching, and stooping) (OR = 1.42, 95% CI = 0.97, 2.08) were also significant factors.

CONCLUSIONS

Results suggest that increasing workers' control over their jobs reduces levels of job strain. Ergonomic strategies and worksite health promotion may help reduce other risk factors.

Interview versus questionnaire for assessing physical loads in the population-based MUSIC-Norrtälje Study

BACKGROUND

MUSIC-Norrtälje study is a case-referent study, the aim of which is to find risk and health factors for low back and neck/shoulder disorders. In this part of the study, the interview technique and the self-administered questionnaire used for assessment of physical loads are described and the inter-method reliability of parts of the self-administered questionnaire is estimated. The distribution of exposure levels in a general population is also described.

METHODS

The study period was three years from November 1993 to November 1996, and the study subjects totaled 2,480 persons (813 female and 610 male referents, 380 female and 315 male low back cases, 252 female and 106 male neck/shoulder cases). The interview concerned "a typical working day" during the preceding 12 months and comprised assessment of energy expenditure, work postures, and manual materials handling for work and leisure time, including regular sport activities. The self-administered questionnaire comprised 18 questions, each covering 5 different points of time: right now, 5, 10, 15, 20 years ago. The answers to eight of the questions about current conditions were compared to corresponding interview responses. The interview was considered as the "gold standard."

RESULTS

Ninety-eight percent of the subjects completed the interview without any great difficulties. According to the interview, the distributions of different exposure levels were generally positively skewed, i.e., the frequency of highly exposed subjects was low in the study base. The correlation between interview and questionnaire responses among the referents was high for time spent "sitting at work" (r = 0.82), "VDU work" (r = 0.87), and work related "motor vehicle driving" (r = 0.80). The correlation was moderate for work-related "hands above shoulder level" (rs = 0.63), and "hands below knee level (trunk flexion)" (rs = 0.66). The correlation was lower for leisure time activities such as "domestic work" (r = 0.55), "time for own activities" (r = 0.39), and "sitting during leisure time" (r = 0.38). Subjects seeking care for low back or neck/shoulder disorder estimated equally correctly or not, as had the referents. However, non-differential misclassification was present in all questions, which will attenuate observed estimates of the relative risk.

CONCLUSIONS

Even though interview data are preferable, questionnaire data may be useful for assessing well-defined work tasks and for "sitting at work."

Shoulder disorders related to work organization and other occupational factors among supermarket cashiers

The study was designed to examine, in 210 supermarket cashiers, the cross-sectional relationships between shoulder disorders according to location and chronicity of pain as well as personal and occupational factors and store and workstation characteristics. The factors associated with shoulder disorders differed for the right and left sides. Age and psychological disorders were significant risk factors. Among occupational factors, duration of employment, job control, wage dependence on efficiency, exposure to cold, movements and postures such as stooping, working with arms above shoulder level and holding heavy loads in position, and using a laser scanner were associated with shoulder disorders, especially on the left. These results confirm the multifactorial origin of shoulder disorders, and show the importance of psychosocial work factors, movements and postures, and the laser scanner as occupational risk factors, and the need to consider right and left shoulder disorders in cashiers separately.

Clarifying the social support theory-research linkage

Social support is a multi-faceted concept that has been difficult to conceptualize, define and measure. Although this concept has been extensively studied, there is little agreement among theoreticians and researchers as to its theoretical and operational definition. As a result, the concept remains fuzzy and almost anything that infers a social interaction may be considered social support. Social support researchers have consistently ignored the complexity of the concept and have measured the variable in a simplistic manner. The purpose of this article is to analyse the linkage between theory and research related to social support by categorizing definitions of social support, exploring the theoretical aspects and conceptualizations of the concept, proposing models of social support, and examining how social support is measured in current social support research (1993-1996). The inadequacy of current research and directions for future study are discussed.

Musculoskeletal symptoms and job strain among nursing personnel: a study over a three year period

OBJECTIVES

To examine the variation of symptoms from the neck, shoulders, and back over a three year period among female nursing personnel and the relation between job strain and musculoskeletal symptoms.

METHODS

At a county hospital the female nursing personnel answered a questionnaire at baseline and then once a year over a period of three years. There were 565, 553, 562, and 419 subjects who answered the questionnaire at the first, second, third, and fourth survey, respectively. Of the study group, 285 nursing personnel answered the questionnaire on four occasions. Ongoing symptoms of the neck, shoulders, and back were assessed by means of a 10 point (0-9) scale with the verbal end points "no symptoms" and "very intense symptoms." Cases were defined as nursing personnel reporting ongoing symptoms, score > 6, from at least one of the body regions. For assessments of job strain, a Swedish version of Karasek and Theorell's model was used.

RESULTS

Of the 285 subjects, 13% were defined as cases at all four assessments, and 46% varied between cases and not cases during the study period. In the repeated cross sectional surveys the estimated rate ratio (RR) for being a case was between 1.1 and 1.5 when comparing the group with job strain and the group without job strain. For the combination of job strain and perceived high physical exertion the estimated RR was between 1.5 and 2.1. When the potential risk factors were assessed one, two, or three years before the assessment of symptoms the estimated RR for becoming a case was between 1.4 and 2.2 when comparing the group with job strain and the group without job strain.

CONCLUSION

Almost half of the healthcare workers varied between being a case and not, over a three year period. The analysis indicated that job strain is a risk factor for musculoskeletal symptoms and that the risk is higher when it is combined with perceived high physical exertion.

The influence of personal variables on work-related low-back disorders and implications for future research

Work-related low-back disorders (LBDs) continue to be one of the single largest sources of compensation costs. The relative contributions of personal, workplace, organizational, and environmental variables to the development and severity of LBDs are not completely understood. The inclusion of personal variables in epidemiologic studies of LBDs has been inconsistent, and different authors have different opinions concerning the importance of such variables. Personal variables either known or suspected to influence outcomes are discussed to elucidate the importance of these variables with respect to understanding LBDs and conducting epidemiological studies in industry. The authors suggest that age, gender, injury history, relative strength, smoking, and psychosocial variables be studied further, and that height, weight, pathologies, genetic factors, maximum oxygen uptake, and absolute strength are unlikely to produce significant effects in industrial populations.