Occupational causes of low-back pain

Exploring the influence of individual factors on the perception of mental workload and body postures

Studies have revealed that physical and mental demands, psychosocial factors, and individual factors can contribute to the development of WMSDs. Yet, much is still unknown regarding the effects of individual characteristics on WMSDs susceptibility. Previous studies discovered people assumed more awkward body postures to perform an activity when the perception of mental workload is higher. This research study explored if individual characteristics such as age, sex, personality, and anxiety help explain changes or differences in the perception of mental workload and body postures assume when performing activities. The study provided evidence that these individual characteristics have a modifying role on perceived mental workload and body postures. The results suggest that perceived mental workload is influenced to a higher extent by individual characteristics such as anxiety, sex, and personality traits. Women have a higher (18.7%) mental workload perception than men. Likewise, NASA-TLX scores are 22% higher for feelers than thinkers. In general, higher perceptions of mental workload were observed in participants with higher anxiety levels. On the other hand, body postures seem to be influenced by different individual factors depending on the nature of the activity. RULA scores increased on average by 13.1% between baseline and time constraint conditions. Larger differences were observed in certain individuals (e.g. introverts (19.7%) and intuitors (13.8%)) across conditions.

Efforts to Control Work Environment Hazards Based on 5S Principles for Smoked Fish Workers

Workstation design can be a potential hazard for workers. A workstation that is arranged following the 5S principles will prevent the exposure of potential work environment hazards such as improper work position that can affect the health of the workers. This research aimed to describe the condition of work station and create a new design a workstation according to 5S principles. This research was quantitative research with cross sectional approach. Samples were taken purposively from 141 smoked fish workers The data on the respondents’ characteristics and potential hazards were analyzed using descriptive analysis. The data were collected using a checklist and a questionnaire. Only several parts of the 5S principles had been applied in the smoked fish workstation. The workstation at the smoked fish production site was not in accordance with 5S principles. The work station has poor hygiene and sanitation condition. New design workstations based on 5S principles with low-cost intervention are proposed to increase the health condition of the workers.

The effects of prolonged sitting, standing, and an alternating sit-stand pattern on trunk mechanical stiffness, trunk muscle activation and low back discomfort

Sit-stand desks continue to be a popular intervention for office work. While previous studies have reported changes in subjective measures, there is limited understanding of how sit-stand work differs from prolonged sitting or standing work, from a biomechanical standpoint. The objective of this study was to investigate the effects of prolonged sitting, prolonged standing, and a sit-stand paradigm on changes in trunk stiffness, low back discomfort, and trunk muscle activation. Twelve healthy participants performed 2 h of computer-based tasks in each protocol, on three different days. The sit-stand protocol was associated with a significant increase in trunk stiffness and a decrease in muscle activation of lumbar multifidus and longissimus thoracis pars thoracis, compared to both prolonged sitting and standing. Both sitting and standing were associated with increased low back discomfort. These findings may be worth exploring in more detail, for why alternating sit-stand patterns may help alleviate low back pain. Practitioner summary: We explored changes in objective and subjective measures related to low back discomfort following prolonged sitting, standing, and alternating sit-stand patterns. Alternating sit-stand pattern was associated with increased trunk stiffness and decreased back muscle activity. Hence, sit-stand desks may have benefits in terms of preventing/mitigating low back pain. Abbreviations: DOF: degree of freedom; EMG: electromyogram; ILL: iliocostalis lumborum pars lumborum; LTL: longissimus thoracis pars lumborum; LTT: longissimus thoracis pars thoracis; LBP: low back pain; LM: lumbar multifidus; MVEs: maximum isometric voluntary exertions; RANOVA: repeated-measure analysis of variance; RMS: root mean square.

Review Article: Is sitting-while-at-work associated with low back pain? A systematic, critical literature review

Objectives: To present a critical review and evaluate recent reports investigating sitting-while-at-work as a risk factor for low back pain (LBP). Methods: The Medline, Embase and OSH-ROM databases were searched for articles dealing with sitting at work in relation to low back pain for the years 1985-97. The studies were divided into those dealing with sitting-while-working and those dealing with sedentary occupations. Each article was systematically abstracted for core items. The quality of each article was determined based on the representativeness of the study sample, the definition of LBP, and the statistical analysis. Results: Thirty-five reports were identified, 14 dealing with sitting-while-working and 21 with sedentary occupations. Eight studies were found to have a representative sample, a clear definition of LBP and a clear statistical analysis. Regardless of quality, all but one of the studies failed to find a positive association between sitting-while-working and LBP. High quality studies found a marginally negative association for sitting compared to diverse workplace exposures, e.g. standing, driving, lifting bending, and compared to diverse occupations. One low quality study associated sitting in a poor posture with LBP. Conclusions: The extensive recent epidemiological literature does not support the popular opinion that sitting-while-at-work is associated with LBP.

Review Article: Is sitting-while-at-work associated with low back pain? A systematic, critical literature review

Objectives: To present a critical review and evaluate recent reports investigating sitting-while-at-work as a risk factor for low back pain (LBP). Methods: The Medline, Embase and OSH-ROM databases were searched for articles dealing with sitting at work in relation to low back pain for the years 1985-97. The studies were divided into those dealing with sitting-while-working and those dealing with sedentary occupations. Each article was systematically abstracted for core items. The quality of each article was determined based on the representativeness of the study sample, the definition of LBP, and the statistical analysis. Results: Thirty-five reports were identified, 14 dealing with sitting-while-working and 21 with sedentary occupations. Eight studies were found to have a representative sample, a clear definition of LBP and a clear statistical analysis. Regardless of quality, all but one of the studies failed to find a positive association between sitting-while-working and LBP. High quality studies found a marginally negative association for sitting compared to diverse workplace exposures, e.g. standing, driving, lifting bending, and compared to diverse occupations. One low quality study associated sitting in a poor posture with LBP. Conclusions: The extensive recent epidemiological literature does not support the popular opinion that sitting-while-at-work is associated with LBP.

Is objectively measured sitting time associated with low back pain? A cross-sectional investigation in the NOMAD study

Background

Studies on the association between sitting time and low back pain (LBP) have found contrasting results. This may be due to the lack of objectively measured sitting time or because socioeconomic confounders were not considered in the analysis.

Objectives

To investigate the association between objectively measured sitting time (daily total, and occupational and leisure-time periods) and LBP among blue-collar workers.

Methods

Two-hundred-and-one blue-collar workers wore two accelerometers (GT3X+ Actigraph) for up to four consecutive working days to obtain objective measures of sitting time, estimated via Acti4 software. Workers reported their LBP intensity the past month on a scale from 0 (no pain) to 9 (worst imaginable pain) and were categorized into either low (≤5) or high (>5) LBP intensity groups. In the multivariate-adjusted binary logistic regression analysis, total sitting time, and occupational and leisure-time sitting were both modeled as continuous (hours/day) and categorical variables (i.e. low, moderate and high sitting time).

Results

The multivariate logistic regression analysis showed a significant positive association between total sitting time (per hour) and high LBP intensity (odds ratio; OR=1.43, 95%CI=1.15-1.77, P=0.01). Similar results were obtained for leisure-time sitting (OR=1.45, 95%CI=1.10-1.91, P=0.01), and a similar but non-significant trend was obtained for occupational sitting time (OR=1.34, 95%CI 0.99-1.82, P=0.06). In the analysis on categorized sitting time, high sitting time was positively associated with high LBP for total (OR=3.31, 95%CI=1.18-9.28, P=0.03), leisure (OR=5.31, 95%CI=1.57-17.90, P=0.01), and occupational (OR=3.26, 95%CI=0.89-11.98, P=0.08) periods, referencing those with low sitting time.

Conclusion

Sitting time is positively associated with LBP intensity among blue-collar workers. Future studies using a prospective design with objective measures of sitting time are recommended.

The global burden of occupationally related low back pain: estimates from the Global Burden of Disease 2010 study

OBJECTIVES

The study was part of the Global Burden of Disease 2010 study and aimed to quantify the burden arising from low back pain (LBP) due to occupational exposure to ergonomic risk factors.

METHODS

Exposure prevalence was based on occupation distribution; estimates of relative risk came from a meta-analysis of relevant published literature. The work-related burden was estimated as disability-adjusted life years (DALYs). Estimates were made for each of 21 world regions and 187 countries, separately for 1990 and 2010 using consistent methods.

RESULTS

Worldwide, LBP arising from ergonomic exposures at work was estimated to cause 21.7 million DALYs in 2010. The overall population attributable fraction was 26%, varying considerably with age, sex and region. 62% of LBP DALYs were in males-the largest numbers were in persons aged 35-55 years. The highest relative risk (3.7) was in the agricultural sector. The largest number of DALYs occurred in East Asia and South Asia, but on a per capita basis the biggest burden was in Oceania. There was a 22% increase in overall LBP DALYs arising from occupational exposures between 1990 and 2010 due to population growth; rates dropped by 14% over the same period.

CONCLUSIONS

LBP arising from ergonomic exposures at work is an important cause of disability. There is a need for improved information on exposure distributions and relative risks, particularly in developing countries.

Predicting back pain treatment outcomes among workers' compensation patients: important information for clinical neuropsychologists

Low back pain is an increasingly prevalent and costly issue in the United States. It is a particularly relevant problem for Workers' Compensation patients, who typically experience worse surgical and functional outcomes than their non-compensated counterparts. Neuropsychologists often provide intervention and assessment services to compensated patients with back pain, and thus it is critical they possess a basic understanding of the factors that might predispose an injured worker to poor spine surgery outcomes. This paper will review the current literature regarding presurgical biopsychosocial factors which have been implicated in poor back surgery outcomes among injured workers. We provide some tentative guidelines for neuropsychologists to utilize in providing services to injured workers with back pain.

Physical activity and low back pain: a systematic review of recent literature

The objective of the study is to systematically evaluate the available evidence on the association between physical activity (i.e. occupational load and non-occupational physical activities) and low back pain (LBP). A systematic approach was used to explore the literature between 1999 and 2009. Studies were selected for inclusion following a comprehensive search of Medline, Embase and CINAHL. The methodological quality of each study was assessed. Studies were considered to be of 'high quality' if they met the cut-off criterion of 60% of the maximum available quality score. Thirty-six cohort or case-control studies were retrieved. Heavy workload and the accumulation of loads or frequency of lifts were moderate to strong risk factors for LBP. Strong associations were found for flexed, rotated and the awkward positions of the lumbar spine. Inconsistent results were found for leisure time physical activities, sports and physical exercise. Studies focusing on daily habitual physical activities (e.g. domestic activities and commuting) in association with LBP are lacking. In conclusion, the occurrence of LBP is related to the nature and intensity of the physical activities undertaken. However, physical activities can be subdivided into separate types and intensities and the ultimate physical load is the sum of all these activities. This makes it difficult to designate one particular activity as the cause of LBP.

Studying the relationship between low back pain and working postures among those who stand and those who sit most of the working day

A relationship between low back pain (LBP) and prolonged standing or prolonged sitting at work has not been clearly shown, despite its biological plausibility. Because sitting and standing postures vary as to duration and freedom to alternate postures, and standing postures vary as to mobility, associations between specific working postures and LBP were explored using multiple logistic regression. Associations between work factors and self-reported LBP during the previous 12 months that interfered with usual activities were examined among 4493 standing workers and 3237 sitting workers interviewed in the 1998 Quebec Health and Social Survey; 24.5% reported significant LBP. Since the same conditions can correspond to different physiological demands for sitting compared with standing workers, analyses were performed separately for the two groups. Standing without freedom to sit was associated with LBP. Different occupational physical and psychosocial factors were associated with LBP in sitting compared with standing populations.

Biomechanical strains and low back disorders: quantifying the effects of the number of years of exposure on various types of pain

OBJECTIVE

To assess the effects of duration of exposure to biomechanical strains on various types of low back pain (LBP).

METHODS

The population study was a random sample from the GAZEL cohort. Durations of exposure to selected biomechanical strains during subjects' working lifetime and potential confounders were assessed in 1996 by self-administered questionnaires. Data on LBP in the previous 12 months were collected in 2001. Relations between various dimensions of LBP and durations of exposure to the biomechanical strains were analysed with multivariate regression models. Polytomous models were built to determine whether some biomechanical strains were specifically associated with some types of LBP.

RESULTS

Analyses were performed separately for men (n = 2218) and women (n = 383). Significant associations were observed (ORs reported are those for 20 years of exposure) between LBP and durations of driving and bending/twisting for men (OR 1.24 and 1.37 respectively); LBP for more than 30 days and duration of exposure to bending/twisting for men and women (OR 2.20 and 2.00 respectively) and duration of driving for women (OR 3.15); LBP radiating to the leg and duration of driving for men (OR 1.43) and bending/twisting for women (OR 1.95); LBP radiating below the knee and duration of exposure to pulling/pushing/carrying for men (OR 1.88). Bending/twisting in both men and women, and driving for women appeared to be stronger risk factors for LBP for more than 30 days. Pulling/pushing/carrying heavy loads appeared to be a risk factor specific for LBP radiating below the knee for men.

CONCLUSION

This study suggests that exposure to biomechanical strains has long-term effects and a dose-response relation with duration of exposure and specific effects for some types of LBP.

Lower back problems and work-related risks in a South African manganese factory

An analytical cross-sectional epidemiological study carried out among 109 manganese plant workers aimed to examine the prevalence and association between lower back problems (LBP) and occupational risk factors. Outcome was defined using a guided questionnaire and a functional rating index. Exposure to occupational risk factors was determined using self-reported questionnaires and workstation analyses. Multivariate logistic regression analyses indicated significant adjusted odds ratios (OR) for prolonged 90 degrees trunk flexion (OR 2.16; CI 1.15-4.05); manual handling (1.89; 1.17-3.08); load carriage (1.54; 1.08-2.19); and lifting (4.61; 1.37-15.47). The findings illustrate regional and occupational specifics of risk for LBP, and indicate that self-selection or adaptation to task-specific demands could possibly lead to observations of ergonomically relevant risk factors, which do not necessarily yield statistically significant associations with LBP. The findings further support multi-modal preventative approaches.

Effects of driving on low back pain

BACKGROUND

Many previous studies have demonstrated that driving a car is a risk factor for low back pain (LBP). We have frequent contact with medical representatives who often drive cars for business, and have noticed that many of them suffer from LBP.

AIMS

To investigate how driving affected the occurrence of LBP in medical representatives.

METHODS

Questionnaire survey of all medical representatives working in Mie Prefecture (Japan).

RESULTS

A total of 551 medical representatives replied (92%). We divided the subjects into Group A (with LBP) and Group B (without LBP). There was no significant difference in mean age, height, weight or duration of continuous employment between the two groups. Mean total mileage was 342 539 km in Group A and 251 945 km in Group B (P < 0.05). There was no significant difference in estimated daily mileage or estimated daily driving time between the two groups. As for backrest inclination, most of the respondents in Group A chose 105 degrees and the majority in Group B chose 120 degrees (P < 0.001).

CONCLUSION

The total mileage was significantly higher in Group A than in Group B. We considered that the risk for LBP increased as the lumbar spine load accumulated day by day while driving a car almost every day without a holiday.

Occupational factors associated with low back pain in urban taxi drivers

BACKGROUND

Urban taxi drivers differ from other professional drivers in their exposures to physical and psychosocial hazards in the work environment. Epidemiological data on low back pain (LBP) of this occupational group are very scarce.

AIMS

To examine LBP in taxi drivers and its association with prolonged driving and other occupational factors.

METHODS

We analyzed the cross-sectional data from the Taxi Drivers' Health Study. Standardized instruments were used to collect information on personal factors, work-related physical and psychosocial factors and driving time profiles. LBP prevalence was assessed using the modified Nordic Musculoskeletal Questionnaire. Multiple logistic regression models were employed for statistical analyses.

RESULTS

Of 1242 drivers, 51% reported LBP in the past 12 months, significantly (P < 0.001) higher than other professional drivers (33%) in Taiwan. After adjusting for the effects of demographic characteristics, lifestyle factors, anthropometric measures and socioeconomic positions, we found that driving time >4 h/day [prevalence odds ratio (POR) 1.78; 95% CI 1.02-3.10], frequent bending/twisting activities while driving (adjusted OR 1.86; 95% CI 1.15-2.99), self-perceived job stress (POR 1.75; 95% CI 1.20-2.55), job dissatisfaction (POR 1.44; 95% CI 1.05-1.98) and registration type were the major occupational factors significantly associated with higher LBP prevalence in taxi drivers.

CONCLUSIONS

We have identified that long driving time and several physical and psychosocial factors are associated with high prevalence of LBP in taxi drivers. This should be further investigated in prospective studies. Future studies are needed to examine the potential adverse effects of prolonged exposure to low levels of whole-body vibration.

Psychosocial factors related to lower back problems in a South African manganese industry

The purpose of this study was to determine the association between the prevalence of lower back problems, fear-avoidance beliefs, and pain-coping strategies in using an analytical cross-sectional epidemiological study among a group of 109 workers in a South African manganese industry. Outcome (LBP) was defined using a guided questionnaire and functional rating indexes. Exposure to psychosocial risk was determined using the Fear-Avoidance Beliefs (FABQ) and Coping Strategies (CSQ) questionnaires. Using inclusive and stringent definitions for perceived LBP, point prevalence was 37.6 and 29.4%, respectively. Only 8 cases of LBP were, however; recorded officially over a 7-year period reflecting a tendency of underreporting. Multivariate logistic regression analyses indicated significant adjusted relative risk ratios (RR) for work-related fear-avoidance beliefs (RR 2.35; 95% CI 1.39-3.95) as a singular psychosocial risk while no specific coping strategy could be isolated. In conclusion, work hardening and a contented ethos of the manual laborers under study moderates the association between the prevalence and etiology of LBP.

Lower back problems and occupational risk factors in a South African steel industry

BACKGROUND

The etiology of work-related back disorders is often population specific. The objective of this study was to identify and establish the association of occupational risk factors with the prevalence of low back (LB) problems in a semi-automated South African Steel industry.

METHODS

The design entailed an analytical cross-sectional epidemiological study among a group of 366 steel plant workers. Outcome of LB problems was defined using a guided questionnaire and a functional rating index. Exposure to occupational risk factors was determined using self-reported questionnaires.

RESULTS

Multivariate logistic regression analyses indicated significant adjusted odds ratios (OR) for twisting and bending (OR 2.81; CI 1.02-7.73); bulky manual handling (5.58; 1.16-26.71); load carriage (7.20; 1.60-32.37); prolonged sitting (2.33; 1.01-5.37); kneeling and squatting (4.62; 1.28-16.60); and working on slippery and uneven surfaces (3.63; 1.20-10.90).

CONCLUSIONS

This study supports the current view of a multifactorial etiology in idiopathic LB problems, and emphasizes the importance of multiple intervention strategies in industrial settings.

Standing, sitting and associated working conditions in the Quebec population in 1998

Working posture is an important determinant of musculoskeletal and vascular health. Knowledge of the context and type of postures is necessary in order to examine their associations with health-related outcomes. This study describes self-reported usual working postures in a population and their associations with other working conditions and demographic variables. The 1998 Quebec Health and Social Survey is a population-based survey of 11,986 private households in the province of Quebec. It contained a self-administered questionnaire, including an extensive occupational health section. The analyses in this study were limited to respondents with paid employment who had at least 6 months seniority in their current job, comprising 9,425 subjects. The overall prevalence of usual work in a standing posture is 58%; it is more common among men, workers under 25 years, those in the two lowest educational quintiles and those with incomes under 20,000 Canadian dollars. Only one person in six who works standing reports being able to sit at will. Women and men differ in the types of usual standing and sitting postures at work. Those who work standing and/or who work in more constrained postures are more likely to be exposed to other physical work demands, such as handling heavy loads, repetitive work, forceful exertion and low job decision latitude. The association between decision latitude and constrained postures is an important link between psychosocial and physical stressors in the workplace. In epidemiological studies, exposure covariation and interactions should be considered in the generation and interpretation of the associations between work postures and musculoskeletal disorders.

[Risk factors for low back pain among taxi drivers in Japan]

We conducted a questionnaire study on low back pain (LBP) and working conditions among male taxi drivers employed in the company in Fukuoka city in order to investigate the occurrence of LBP and occupational factors related to LBP among taxi drivers. The study was undertaken through two questionnaires, the first conducted in 1999 (n = 280, first cross-sectional study), the second conducted in 2001 (n = 284, second cross-sectional study). The questionnaire results were used to conduct two analyses: 1) the one-year prevalence of LBP and the relationship between LBP and occupational factors in the second cross-sectional study, and 2) the incidence of LBP and the relationship between LBP and occupational factors from the first to the second cross-sectional study in the longitudinal study. The incidence cases were defined as subjects who met the following conditions: those who had never experienced LBP at the time of the first study but had experienced LBP during the previous year at the time of the 2nd study. The one-year prevalence (45.8%) of LBP among taxi drivers was comparable to rates reported for other occupational drivers in which LBP occurs frequently. This result indicates that LBP is an important health problem for taxi drivers, and an urgent occupational safety and health management issue. The two-year incidence of LBP among the taxi drivers was estimated at 25.9%. LBP was significantly related with the suitability of the driver's seat pan, total mileage on the taxi (total mileage), the level of uncomfortable vibrations on the road, job stress and time employed as a taxi driver. Importantly, the prevalence of LBP increased with increasing total mileage, a finding which had not previously been reported. The findings of this study also suggest that ergonomic problems with the driver's seat pan, whole-body vibration (WBV) and job stress may contribute to LBP among taxi drivers. Further study is needed to confirm how total mileage contributes to LBP. Furthermore, WBV during normal use of taxies should be measured in order to evaluate the association between WBV and LBP.

Neuromusculoskeletal disorders in the neck and upper extremities among drivers of all-terrain vehicles--a case series

BACKGROUND

The purpose of this study was to investigate whether professional drivers of all-terrain vehicles (ATVs) with neck pain have a different array of neuromusculoskeletal disorders in the neck and upper extremities than a referent group with neck pain from the general population. It is hypothesized that exposure to shock-type vibration and unfavorable working postures in ATVs have the capacity to cause peripheral nervous lesions.

METHODS

This study was based on a case series analyzed according to a case-case comparison design. The study population consisted of 60 male subjects, including professional drivers of forest machines (n = 15), snowmobiles (n = 15), snowgroomers (n = 15) and referents from the general population (n = 15) all of whom had reported neck pain in a questionnaire and underwent an extensive physical examination of the neck and upper extremities. Based on symptom history, symptoms and signs, and in some cases chemical, electroneurographical and radiological findings, subjects were classified as having a nociceptive or neuropathic disorder or a mix of these types.

RESULTS

The occurrence of asymmetrical and focal neuropathies (peripheral nervous lesion), pure or in a mix with a nociceptive disorder was common among cases in the ATV driver groups (47%-79%). This contrasted with the referents that were less often classified as having asymmetrical and focal neuropathy (27%), but instead had more nociceptive disorders. The difference was most pronounced among drivers of snowgroomers, while drivers of forest machines were more frequently classified as having a nociceptive disorder originating in the muscles.

CONCLUSION

This study found a high prevalence of assymetrical and focal neuropathies among drivers with pain in the neck, operating various ATVs. It seems as if exposure to shock-type whole-body vibration (WBV) and appurtenant unfavorable postures in ATVs may be associated to peripheral nervous lesions.

Is undergraduate physiotherapy study a risk factor for low back pain? A prevalence study of LBP in physiotherapy students

BACKGROUND

Following reports of high prevalence of low back pain (LBP) in young physiotherapists, we investigated whether LBP was a problem for undergraduate physiotherapy students.

METHOD

Physiotherapy students enrolled in one Australian tertiary institution completed a validated self-administered questionnaire in April 2001, seeking information on LBP prevalence (lifetime, 12 month, one-month, one-week), and its risk factors. The survey incorporated the Nordic back questionnaire, questions on common risks for LBP, and purpose-built questions regarding educational exposures. Univariate logistic regression models were applied to test associations.

RESULTS AND DISCUSSION

72% students responded. LBP prevalence was 69% (lifetime), 63% (12-month), 44% (one-month), 28% (one-week). The risk of LBP increased significantly for students once they completed first year. Being aged 20 or 21 years (final year students) was significantly associated with all measures of LBP, compared with the youngest students. Exposure to tertiary study of greater than two years was associated with lifetime, 12 month and one-month LBP prevalence. Spending more than 20 hours in the past month 'sitting looking down' was significantly associated with one-month LBP prevalence. Similar exposure to 'treating patients' was significantly associated with one-month and one-week LBP prevalence.

CONCLUSIONS

Physiotherapy students should be alerted to the likelihood of LBP and is potential causes during their training, so that they enter the workforce with reduced risk of LBP. The potential for other undergraduate students to suffer LBP should also be considered.

Stressful psychosocial work environment increases risk for back pain among retail material handlers

BACKGROUND

Back pain is a major source of lost work time. Occupational physical activity only accounts for a fraction of low back pain; therefore, there is growing interest in investigating other possible causes of back pain including the psychosocial work environment.

METHODS

Material handlers (N = 6,311) in 160 newly opened stores were interviewed at study entry and approximately 6 months later. Factor analysis was used to reduce the 37 psychosocial questionnaire items to seven distinct factors.

RESULTS

After adjusting for history of back problems and work-related lifting, risk of back pain was moderately increased among employees who reported high job intensity demands (odds ratio (OR) = 1.8), job dissatisfaction (OR = 1.7), and high job scheduling demands (OR = 1.6).

CONCLUSIONS

Modification of the psychosocial work environment for material handlers in large retail stores may help reduce back pain among employees.

Estudo epidemiologico dos coletores de lixo seletivo

O artigo aborda epidemiologicamente o perfil dos coletores de lixo seletivo e descreve as lesões musculares e acidentes de trabalho mais freqüentes. Este estudo transversal foi desenvolvido com duas empresas (denominadas como empresa A e empresa B), em Porto Alegre, selecionando-se 50 funcionários aleatoriamente (presentes e aptos nos dias das entrevistas para a pesquisa) e aos quais foi aplicado um questionário. A Média de idade da amostra foi de 34 e 22 anos para a empresa A e B, respectivamente. Cerca de 66% dos funcionários da empresa B trabalham a menos de 5 anos na companhia, ao passo que 95% dos funcionários da empresa A trabalham há mais de 5 anos. O índice de lesões entre as duas empresas é alta 90% e 46,6% para empresas A e B, respectivamente. Lesões são mais comuns nos membros inferiores, seguidas pelas lesões dos membros superiores e da coluna. Ambas as empresas apresentavam deficiência do uso de equipamentos de proteção, sendo estes praticamente ignorados pelos funcionários, embora de uso obrigatório. As avaliações médicas são realizadas esporadicamente, sem acompanhamento regular. Ambas as empresas apresentam altos índices de leões em geral, sendo as lesões de membros inferiores mais comuns. Também são altos os índices de cortes e outros pequenos ferimentos, provavelmente pelo não uso de equipamentos de proteção obrigatórios.

Working hours spent on repeated activities and prevalence of back pain

BACKGROUND AND AIMS

Back pain is the most common reason for filing workers' compensation claims in the United States and affects large numbers of workers in many other countries. To evaluate the associations between working hours spent on repeated activities and back pain, data gathered through the 1988 National Health Interview Survey were analysed. The data were also used to identify high risk occupations.

METHODS

A total of 30 074 workers participated in the survey. They were asked to provide information on their job, including the time spent on repeated strenuous physical activities (RSPA) and the time spent on repeated bending, twisting, or reaching (RBTR) on a typical job. A case of back pain was defined as a worker who had back pain every day for a week or more during the past 12 months. Each case was asked to report the cause of back pain. Those who attributed their back pain to repeated activities (RA) or a single accident or injury (AI) were asked to recall whether they performed RA or had the AI at work.

RESULTS

Whereas the prevalence of back pain increased as the number of working hours spent on RSPA or RBTR increased, the dose-response relations were not linear for either factor, suggesting the involvement of other unmeasured factors. The estimated overall prevalence of RA back pain was 8.9% among male workers and 5.9% among female workers. "Carpenters" had the highest prevalence (19.2%) and most cases (338 000) among the major occupations of men, and "nursing aides, orderlies, and attendants" had the highest prevalence (15.2%) and most cases (217 000) among the major occupations of women.

CONCLUSIONS

The number of hours spent on repeated activities at work was associated with the prevalence of back pain. This study identified high risk occupations for future research and intervention.

Perceived work stress, overcommitment, and self-reported musculoskeletal pain: a cross-sectional investigation

The objective of this study was to analyze associations of three indicators of perceived work stress (physical job demand, low control at work, and an imbalance between effort and reward), and of overcommitment, a personal pattern of coping with work demands, with musculoskeletal pain. A standardized questionnaire measuring these conditions in addition to self-reported musculoskeletal pain at different locations was administered to a group of 316 male and female employees of a public transport enterprise. After we adjusted for confounding effects of age, sex, socioeconomic status, shift work, and negative affectivity, we observed elevated prevalence odds ratios in employees who scored high on overcommitment, who were exposed to physical job demand, and, to a lesser extent, who reported psychosocial work stress. Results have implications for a more comprehensive approach to primary and secondary prevention of musculoskeletal pain.

Organisational downsizing and musculoskeletal problems in employees: a prospective study

OBJECTIVES

To study the association between organisational downsizing and subsequent musculoskeletal problems in employees and to determine the association with changes in psychosocial and behavioural risk factors.

METHODS

Participants were 764 municipal employees working in Raisio, Finland before and after an organisational downsizing carried out between 1991 and 1993. The outcome measures were self reports of severity and sites of musculoskeletal pain at the end of 1993 and medically certified musculoskeletal sickness absence for 1993-5. The contribution of changes in psychosocial work characteristics and health related behaviour between the 1990 and 1993 surveys was assessed by adjustment.

RESULTS

After adjustment for age, sex, and income, the odds ratio (OR) for severe musculoskeletal pain between major and minor downsizing and the corresponding rate ratios for musculoskeletal sickness absence were 2.59 (95% confidence interval (95% CI) 1.5 to 4.5) and 5.50 (3.6 to 7.6), respectively. Differences between the mean number of sites of pain after major and minor downsizing was 0.99 (0.4 to 1.6). The largest contribution from changes in work characteristics and health related behaviour to the association between downsizing and musculoskeletal problems was from increases in physical demands, particularly in women and low income employees. Additional contributory factors were reduction of skill discretion (relative to musculoskeletal pain) and job insecurity. The results were little different when analyses were confined to initially healthy participants.

CONCLUSIONS

Downsizing is a risk factor for musculoskeletal problems among those who remain in employment. Much of this risk is attributable to increased physical demands, but adverse changes in other psychosocial factors may also play a part.

Dutch Musculoskeletal Questionnaire: description and basic qualities

A questionnaire ('Dutch Musculoskeletal Questionnaire', DMQ) for the analysis of musculoskeletal workload and associated potential hazardous working conditions as well as musculoskeletal symptoms in worker populations is described and its qualities are explored using a database of 1575 workers in various occupations who completed the questionnaire. The 63 questions on musculoskeletal workload and associated potentially hazardous working conditions can be categorized into seven indices (force, dynamic and static load, repetitive load, climatic factors, vibration and ergonomic environmental factors). Together with four separate questions on standing, sitting, walking and uncomfortable postures, the indices constitute a brief overview of the main findings on musculoskeletal workload and associated potentially hazardous working conditions. Homogeneity of the indices is satisfactory. The divergent validity of the indices is fair when compared with an index of psychosocial working conditions and discomfort during exposure to physical loads. Worker groups with contrasting musculoskeletal loads can be differentiated on the basis of the indices and other factors. With respect to the concurrent validity, it appears that most indices and factors show significant associations with low back and/or neck-shoulder symptoms. This questionnaire can be used as a simple and quick inventory for occupational health services to identify worker groups in which a more thorough ergonomic analysis is indicated.

Predictors of low back pain onset in a prospective British study

OBJECTIVES

This study examined predictors of low back pain onset in a British birth cohort.

METHODS

Univariate and multivariate analyses focused on individuals who experienced onset of low back pain at 32 to 33 years of age (n= 571) and individuals who were pain free (n = 5210). Participants were members of the 1958 British birth cohort.

RESULTS

Incident pain was elevated among those with psychological distress at 23 years of age (adjusted odds ratio [OR] = 2.52, 95% confidence interval [CI] = 1.65, 3.86) and among persistent moderate or heavy smokers (adjusted OR = 1.63, 95% CI = 1.23, 2.17). Significant univariate associations involving other factors (e.g., social class, childhood emotional status, body mass index, job satisfaction) did not persist in multivariate analyses.

CONCLUSIONS

This prospectively studied cohort provides evidence that psychological distress more than doubles later risk of low back pain, with smoking having a modest independent effect. Other prospective studies are needed to confirm these findings before implications for low back pain prevention can be assessed.

The influence of organizational factors on occupational low back injuries

The unique home care environment puts nurses at risk of low back injuries. Protecting nurses may mean the difference between delivering cost-effective quality care and no care at all. This study, conducted in Alberta, Canada, disclosed a lack of organizational resources and use of occupational health services in home care providers. Involving frontline staff as management partners may provide a solution for the development of an effective injury prevention program in home care.

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.

The role of physical and psychological factors in occupational low back pain: a prospective cohort study

OBJECTIVE

To examine risk factors for onset of low back pain (LBP) in healthcare workers.

METHODS

Nursing students, during their 3 year training period, and 1 year after training were studied in a prospective cohort study, with repeated self reported measurements of determinants of LBP at 6 monthly intervals for 3 years during training, and after a 12 month interval there was an additional final follow up.

RESULTS

During training, increased risk of new episodes of LBP was associated with having had LBP at baseline, with part time work, and with a high score on the general health questionnaire (GHQ). A high GHQ score preceded the onset of LBP, in such a way that a high score at the immediately previous follow up increased risk of LBP at the next follow up. 12 Months after training, a history of recurring LBP during training increased the risk of a new episode as did having obtained work as a nurse. A high GHQ score at this follow up was also associated with a concurrently increased risk. Pre-existing GHQ score, either at the end of training or at baseline, had no effect on risk of LBP 12 months after training.

CONCLUSIONS

Other than a history of LBP, pre-existing psychological distress was the only factor found to have a pre-existing influence on new episodes of LBP. Increased levels of psychological distress (as measured by the GHQ) preceded the occurrence of new episodes of pain by only short intervening periods, implying a role for acute distress in the onset of the disorder. This finding suggests that management of the onset of occupational LBP may be improved by management of psychological distress.

[Subjective pain and tenderness in low back among care workers in relation to work load and daily life]

Five hundred and fifty-two care-workers aged 20 to 60 years, who worked at six custodial-care homes, were examined to clarify the relationship between subjective pain and tenderness in the low back, together with the factors affecting occupational low back pain. Subjects who were diagnosed as having tenderness in the low back by one medical practitioner at the time of health examinations, and those who reported the presence of low back pain in self-rating questionnaires were defined as those with "objective" and "subjective" low back pain, respectively. Complaints concerning workloads and daily life, as well as musculoskeletal and systemic symptoms, were inquired of in the self-rating questionnaires; the former complaints were compiled into four factors representing "environmental load at work," "physical load at work," "mental load at work," and "daily life" by the factor analysis. The corresponding rates in subjective and objective low back pains were 67.0% in 188 male care workers and 70.9% in 364 female care workers. In males and females, "physical load at work" was positively related to subjective low back pain (P < 0.05) with the use of the multiple logistic regression analysis including all the causal and confounding factors. Musculoskeletal symptoms in females were also positively related to subjective and objective low back pain (P < 0.05). These data suggest that subjective low back pain clearly reflects the problem of occupational low back pain as a whole, and that low back pain is mainly related to the physical load at work in care workers.

The association between cigarette smoking and back pain in adults

STUDY DESIGN

A retrospective cohort study of adolescent idiopathic scoliosis. A comparison group of persons without scoliosis was also selected randomly from the general population.

OBJECTIVES

To estimate the association between level of cigarette smoking and the prevalence and severity of back pain.

METHODS

A postal questionnaire was used to elicit information on smoking histories, a variety of indices of low back pain, and potential confounding factors. The association between smoking and back pain was estimated separately for men and women in the cohort and in the comparison group using ordinal regression models.

RESULTS

The questionnaire was completed by 1287 women and 184 men who had adolescent idiopathic scoliosis and by 1130 women and 621 men in the comparison population who did not have scoliosis. Statistically significant associations between back pain and current cigarette smoking were found in the two groups of women and men with scoliosis, but not among men selected from the general population. In the three former groups, proportional odds ratios comparing current smokers to persons who never smoked ranged from 1.4 to 1.9. Among current smokers, the prevalence of back pain increased with cigarette consumption, and the proportional odds ratios ranged from 1.2 to 1.8 per 10 pack-years (no. of cigarettes smoked per day x no. of years/20). In these three groups, intensity, frequency, and duration of episodes of back pain also were found to increase with smoking consumption.

CONCLUSION

The finding that smokers have more frequent episodes of back pain may imply that smoking exacerbates back pain, and the observation that stronger associations between back pain and smoking were found in the scoliosis cohort suggests that smoking may have a greater impact on persons with damaged spines.

Interactions between physical and psychosocial risk factors at work increase the risk of back disorders: an epidemiological approach

OBJECTIVES

To investigate the possible interactions between physical and psychosocial risk factors at work that may be associated with self reported back disorders.

METHODS

891 of 1514 manual workers, delivery drivers, technicians, customer services computer operators, and general office staff reported risk factors at work and back disorders with a self administered questionnaire (59% return rate). Of the 869 respondents with a valid questionnaire, 638 workers were classified in to one of four exposure groups: high physical and high psychosocial; high physical and low psychosocial; low physical and high psychosocial; and low physical and low psychosocial. Low physical and low psychosocial was used as an internal reference group. The exposure criteria were derived from existing epidemiological publications and models for physical and psychosocial work factors. The frequency and amplitude of lifting and the duration spent sitting while experiencing vibration were used as physical exposure criteria. Ordinal values of mental demands, job control, and social support from managers and coworkers were used as psychosocial exposure criteria.

RESULTS

The highest increase in risk was found in the high physical and high psychosocial exposure group for symptoms of back disorders. In the crude and multivariate analyses, a departure from an additive risk model was found for the 7 day prevalence of symptoms of a low back disorder and also for a recurrent back disorder not present before the current job but also experienced in the past 7 days.

CONCLUSION

This study suggests that an interaction between physical and psychosocial risk factors at work may exist to increase the risk of self reported back disorders. Ergonomic prevention strategies that aim to minimise the risks of symptoms of work related back disorders should not only focus on physical but also on psychosocial risk factors at work. The greatest benefits are likely to be realised when both physical and psychosocial factors are put right.

Are risk factors for atherothrombotic disease associated with back pain sickness absence? The Whitehall II Study

STUDY OBJECTIVE

To explore the previously stated hypothesis that risk factors for atherothrombotic disease are associated with back pain.

DESIGN

Prospective (mean of four years of follow up) and retrospective analyses using two main outcome measures: (a) short (< or = 7 days) and long (> 7 days) spells of sickness absence because of back pain reported separately in men and women; (b) consistency of effect across the resulting four duration of spell and sex cells.

SETTING

14 civil service departments in London.

PARTICIPANTS

3506 male and 1380 female white office-based civil servants, aged 35-55 years at baseline.

MAIN RESULTS

In age adjusted models, low apo AI was associated with back pain across all four duration-sex cells and smoking was associated across three cells. Six factors were associated with back pain in two cells: low exercise and high BMI, waist-hip ratio, triglycerides, insulin and Lp(a). On full adjustment (for age, BMI, employment grade and back pain at baseline), each of these factors retained a statistically significant effect in at least one duration-sex cell. Triglycerides were associated with short and long spells of sickness absence because of back pain in men in fully adjusted models with rate ratios (95% confidence intervals) of 1.53 (1.1, 2.1) and 1.75 (1.0, 3.2) respectively. There was little or no evidence of association in age adjusted models with: fibrinogen, glucose tolerance, total cholesterol, apoB, hypertension, factor VII, von Willebrand factor, electrocardiographic evidence of coronary heart disease and reported angina.

CONCLUSIONS

In this population of office workers, only modest support was found for an atherothrombotic component to back pain sickness absence. However, the young age of participants at baseline and the lack of distinction between different types of back pain are likely to bias the findings toward null. Further research is required to ascertain whether a population sub-group of atherothrombotic back pain can be identified.

[Ergonomics and the occupational activities of the nursing staff]

This paper discusses some of the ergonomics conditions that contribute to the development of musculoskeletal disorders of the vertebral column and relates these conditions to the occupational activities of the nursing staff.

Back problems and atherosclerosis. The Study of Osteoporotic Fractures

STUDY DESIGN

A cross-sectional and prospective study of osteoporotic fractures.

OBJECTIVES

To investigate the correlation between lower extremity arterial disease or history of cardiovascular disease and back pain, back function, osteoporosis, and vertebral fractures.

BACKGROUND

It has been postulated that atherosclerosis may compromise blood flow to bone and soft tissues in the back, causing pain and disability. Recent studies have presented conflicting results.

METHODS

At baseline, information on back pain and function, general functional status, cardiovascular history, and general lifestyle variables was obtained from 1492 elderly white women (mean age, 71 years) enrolled in the Study of Osteoporotic Fractures. Lateral radiographs of the lumbar and thoracic spine were obtained, and lower extremity arterial disease was assessed. Follow-up information was obtained an average of 3.7 years later.

RESULTS

At baseline, 82 women had arterial disease, 443 had a history of cardiovascular disease, and 277 had vertebral fractures; 58 women had one or more additional vertebral fractures during the follow-up period. After adjustment for age, women with cardiovascular disease were more likely to have back pain and disability as a result of the back pain than women free of cardiovascular disease; at the follow-up examination, the back-related disability was more than twice as likely to have worsened in the cardiovascular disease group. No correlation was found between arterial disease and back problems. Neither the prevalence of vertebral fractures at baseline, nor the incidence of vertebral fractures was associated with the presence of arterial disease or cardiovascular disease.

CONCLUSIONS

Results indicated that back problems in elderly women are associated with self-reported cardiovascular disease, but not with objectively assessed lower extremity arterial disease.

Does the menstrual cycle and use of oral contraceptives influence the risk of low back pain? A prospective study among female soccer players

Female sex hormones have been suggested to affect the risk of low back pain. One reason is the fact that back pain is a very common symptom during pregnancy. It also seems to be a more common problem among female than male athletes, e.g. in soccer. Although there are few scientific data supporting a relationship between female sex hormones, use of oral contraceptives and low back pain, many doctors and physiotherapists advise women with low back pain to avoid oral contraceptives. The aim of this study was to evaluate whether low back pain fluctuated during the menstrual cycle and differed between women using and not using oral contraceptives. A questionnaire was sent to 12 female soccer teams; 261 players answered and 50 players (28 with back pain and 22 controls) fulfilled the prospective study. At baseline the players underwent a thorough clinical examination and then filled in a diary concerning menstrual data, back pain, training and matches during one season. A total of 296 menstrual cycles was analysed. No difference in prevalence or severity of back pain was seen between the different phases of the menstrual cycle or between users and non-users of oral contraceptives. Our data do not support the hypothesis that low back pain is influenced by hormonal fluctuations during the menstrual cycle or by use of oral contraceptives.

Work environment and low back pain: the influence of occupational activities

OBJECTIVES

To find associations between the prevalence of low back pain and occupational activities.

METHODS

Interviews of a random sample of 5185 19-59 year old Danish employees analysed by logistic regression.

RESULTS

Increased risks of low back pain were found for "vibration affecting the whole body" (odds ratio (OR) = 1.28), "physically hard work" (OR = 1.28), "frequently twisting or bending" (OR = 1.71), "standing up" (OR = 1.20), and "concentration demands" (OR = 1.28). In the analysis of dose-response relations between low back pain and the risk factors, the one year period prevalence increased with increasing exposure time during a working day to each of the risk factors. The prevalence proportion ratio for those reporting to be exposed for most of the working time were 1.30 for vibrations affecting the whole body, 1.54 for physically hard work, 1.48 for frequently twisting or bending, 1.29 for standing up, and 1.13 for concentration demands. These associations seemed to be stronger in the subset of subjects who worked for 37 hours or more per week. The population attributable fractions were 15.1% for frequently twisting or bending, 15.0% for standing up, 7.6% for concentration demands, and 4.4% for physically hard work.

CONCLUSION

Vibrations affecting the whole body, physically hard work, frequently twisting or bending, standing up, and concentration demands proved to be risk factors for the occurrence of low back pain, even after controlling for age, sex, educational level, and duration of employment in a specific occupation.

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.

Back Pain among U.S. Workers: Comparison of Worker Attributes According to Self-reported Causes of Back Pain

Back pain is a significant health problem, especially in industry. To gain a better understanding of back pain in light of its diverse causality, data for 29,322 working adults interviewed in the Occupational Health Supplement to the 1988 National Health Interview Survey were analyzed by self-reported cause of back pain. The 12-month prevalences of back pain for "injury or repeated activities at work," "injury or repeated activities not at work," and "other reasons," were 9.1%, 4.4%, and 4.0%, respectively. The worker attributes and work impacts associated with these self-reported causes were compared for this nationally representative sample. Results from multivariate logistic regressions indicated different profiles of worker attributes among the three cause-specific subgroups of back-pain sufferers. Work impact was substantial in all cases, but was highest for workers with work-related back pain.

The relation of self-reported back pain to psychosocial, behavioral, and health-related factors in a working population in Switzerland

Back pain causes a considerable loss of working days as well as health care costs and therefore represents a major public health problem in industrialized countries. Psychosocial factors have received increasing attention from researchers studying the causal factors of non-specific back pain. However, most studies focus on few dimensions, like individual or work-related factors. We studied the simultaneous association of various factors representing psychosocial, behavioral, and health-related dimensions to self-reported back pain. Data from the Berne Workplace Health Project on 850 employed men and women was analyzed. Back pain was operationalized by a dichotomized variable (having suffered moderately to severely from back pain in the preceding four weeks). The theoretical model guiding the underlying project was a general demand-resource model. Variables that--according to that model--were hypothesized to be related to back pain as well as more specific factors--like physical work load--were analyzed by stepwise logistic regression analysis. In men, there was a statistical trend (P < 0.1) for several work-related factors (low job discretion, high job demands, low job satisfaction). In women, dissatisfaction with salary was the only work-related factor associated with back pain. There was no significant association between private context factors, like poor social network or high demands/low control, and back pain. Only in men, the likelihood of back pain increased with age, while only in women, back pain was associated with emotional problems (individual factors). Among the behavioral factors, smoking was associated to back pain in men, while in women none of the behavioral factors was significant. In both men and women reporting more than two functional symptoms and a history of intestinal problems were associated to back pain. All of our findings were in the expected direction, i.e., it was invariably unfavorable categories of explanatory variables that were associated with higher prevalence of back pain. However, most associations seem to be quite unspecific. There is a need for theoretically guided research aiming at the development of a more complex process model of back pain.

A one-year prospective study on back pain among novice golfers

We conducted a 1-year follow-up study on back pain among 196 men taking up golf. A questionnaire on individual characteristics, occupation, sports, and back pain was distributed at the start of the study and was followed by another questionnaire after 12 months. Eleven percent of the original subjects (25 of 211) were lost to followup, but withdrawal from the survey was not associated with health status. In the baseline survey (N = 221), the self-reported lifetime cumulative incidence of back pain was 63%; 28% reported back pain during the month before answering the questionnaire, and 13% reported current back pain. Athletes had an increased odds ratio of 2.1 (95% confidence interval, 1.1 to 4.0) for previous back pain. During the 12 months between the surveys, the incidence of first-time back pain was 8% and the incidence of recurrent back pain was about 45%. Men involved in golf and another sport demonstrated a risk of 1.4 for recurrence of back pain, compared with men playing golf only. Six subjects attributed the recurrent back pain to playing golf. Given the high proportion of athletes in this study (68%), the risk factor of playing golf failed to demonstrate an additional significant effect on the general relationship between sport and back pain.

A national cross-sectional study in the Danish wood and furniture industry on working postures and manual materials handling

Musculoskeletal disorders constitute a major problem in the wood and furniture industry and identification of risk factors is needed urgently. Therefore, exposures to different work tasks and variation in the job were recorded based on an observation survey in combination with an interview among 281 employees working in wood working and painting departments. A questionnaire survey confirmed high frequencies of symptoms from the musculoskeletal system: The one-year prevalence of symptoms from the low back was 42% and symptoms from the neck/shoulder was 40%. The exposure was evaluated based on: (1) classification of work tasks, (2) work cycle time, (3) manual materials handling, (4) working postures, and (5) variation in the job. Among the employees 47% performed feeding or clearing of machines, 35% performed wood working or painting materials, and 18% performed various other operations. Among the employees 20% had no variation in their job while 44% had little variation. Manual materials handling of 375 different burdens was observed, which most often occurred during feeding or clearing of machines. The weight of burdens lifted was 0.5-87.0 kg, where 2% had a weight of more than 50 kg. Among the lifting conditions 30% were evaluated as implying a risk of injury. An additional risk factor was the high total tonnage lifted per day, which was estimated to range from 132 kg to 58,800 kg. Working postures implied a risk of injury due to prolonged forward and lateral flexions of the neck, which was seen most frequently during wood working or painting materials. These data substantiate the finding that work tasks mainly during feeding or clearing of machines imply a risk of injury to the low back and a risk of injury to the neck and shoulder area mainly during wood working or painting materials. Optimal strategies for job redesign may be worked out by using these data in order to prevent occupational musculoskeletal disorders.

[An epidemiological study on the relationship between musculoskeletal disorders and work load]

965 workers engaged in working tasks of work intensity grade 2, 3, 4 (based on Chinese National Standard) were investigated on the musculoskeletal disorders with a questionnaire. The lumbar vertebra of 136 randomly chosen workers were also radiologically examined. The result revealed that the prevalence of low-back disorders was 51.2% on average and it was obviously correlated with such factors as age, standing, previous back injury, education level, sport activity, work intensity, working posture, satisfaction with the tools as well as work condition and house work. Heavy work load and unneutral working posture were proved to be the main factors as revealed by the multifactor analysis and further supported by the findings of X-ray examination.

[Lifestyle and work of nursing personnel and back pain]

This paper is part of a broader study. In order to describe life style and occupational history possibly related to back pain, 75 female workers of the nursing staff from a University Hospital were interviewed during clinical evaluation.

CONSIDERAÇÕES SOBRE UMA AVALIAÇÃO CLÍNICA ESPECÍFICA DA COLUNA VERTEBRAL EM TRABALHADORES DE ENFERMAGEM

Este trabalho é parte de um estudo mais abrangente. Um grupo interdisciplinar realizou uma avaliação clínica especifica em 75 funcionárias da enfermagem, com o objetivo de demonstrar o diagnóstico e detectar defeitos posturais e alterações musculoligamentares.