Musculoskeletal symptoms and associated risk factors in a large sample of Chinese workers in Henan province of China

Musculoskeletal symptoms among workers of the pulp and paper industry: the contribution of age, gender, body mass index and physical activity level

Objectives. This study aimed to investigate 12-month and 7-day prevalence of musculoskeletal symptoms among workers of the pulp and paper industry, and assess the contribution of age, gender, body mass index (BMI) and physical activity (PA). Methods. The sample comprised 904 workers. Musculoskeletal symptoms were assessed using the Nordic musculoskeletal questionnaire. χ2 tests assessed the association between musculoskeletal symptoms and age/gender/BMI/PA, and multivariate logistic regression models predicted the 12-month occurrence of symptoms in the five most prevalent regions. Results. The five most affected body regions were the lower back, shoulders, neck, knees and wrists/hands. Older workers presented more symptoms in all body regions, except dorsal; female gender was associated with neck symptoms (p = 0.001); overweight was associated with a higher prevalence of lower back (p = 0.01), knee (p = 0.017) and ankle/foot (p = 0.037) symptoms; and a moderate PA level was associated with thigh/hip symptoms (p = 0.006). Age was a significant predictor in all five most affected regions; gender was a significant predictor for shoulders, neck and wrists/hands; and BMI was a significant predictor for lower back symptoms. Conclusion. The 12-month and 7-day prevalence of musculoskeletal symptoms among workers of the pulp and paper industry is higher in the lower back, shoulders, neck, knees and wrists/hands.

The impact of the digital economy on occupational health: A quasi-experiment based on "Broadband China" pilot

The recent years' booming digital economy can not only benefit businesses, but also be an important way to improve people's wellbeing. This paper aimed to identify the relationship between the digital economy based on the "Broadband China" pilot policy and occupational health by applying DID method. The empirical results highlight that occupational health in the pilot cities of "Broadband China" are significantly improved compared with those in non-pilot cities, indicating that the digital economy can significantly improve occupational health. However, this effect varies across regions with different levels of economic development. Compared with developed areas, the digital economy has a more obvious effect on the improvement of occupational health in less developed areas, which indicates that this effect conforms to the law of diminishing marginal effect. Therefore, the digital economy should be continuously promoted to improve occupational health. Governments at all levels should strengthen the network infrastructure to provide a good basic environment for the development of the digital economy. At the same time, governments should introduce more detailed digital economy goals and programs according to the actual situation of their jurisdictions to fully release the economic and social benefits of the digital economy.

Psychosocial risk factors for low back pain in US workers: Data from the 2002-2018 quality of work life survey

BACKGROUND

Examining workplace psychosocial risk factors for back pain becomes increasingly important because of the changing nature of work and rising healthcare costs. Some psychosocial risk factors for back pain, such as work and family imbalance, exposure to a hostile work environment, and job insecurity, are understudied for the working population in the United States.

METHODS

Data used in this study came from the Quality of Work Life Survey (QWL), a supplementary module of the General Social Survey conducted in the United States. Data from the 2002, 2006, 2010, 2014, and 2018 QWL surveys were used in these analyses, giving a total sample size of 6661. Five domains of workplace psychosocial risk factors for back pain were examined, including job strain, low social support, work-family imbalance, exposure to a hostile work environment (harassment and discrimination), and job insecurity. The adjusted odds ratio (aOR) of each psychosocial risk factor for back pain with 95% confidence intervals (CI) was estimated using a multivariable logistic regression model after controlling for job physical factors, occupation, and demographic and socioeconomic characteristics.

RESULTS

Significant associations were found between back pain and several psychosocial factors including job strain (aOR 1.19; CI 1.00,1.41), work-family imbalance (aOR,1.42; CI 1.22,1.64), harassment (aOR 1.40; CI 1.15,1.71), and discrimination (aOR 1.20 CI 1.00,1.44).

CONCLUSION

This study contributes to the understanding of the relationship between a variety of workplace psychosocial factors and back pain. Our findings suggest directions in future longitudinal research to examine emerging workplace psychosocial factors for back pain.

Prevalence status and associated factors of wrist postural injury in the Chinese occupational population

Objective

This study investigated the prevalence of wrist injuries in 15 industries and different types of work in China. Study on the associated factors of wrist injuries provides a scientific basis for prevention and treatment of wrist diseases in occupational workers.

Methods

A cross-sectional study of musculoskeletal symptoms of related practitioners in 15 industries, including automobile manufacturing, was conducted to retrieve worker demographic information, working wrist posture, and pain conditions. Multivariable binary logistic regression analyses were performed to identify factors associated with work-related musculoskeletal disorders (WMSDs).

Results

The prevalence of wrist injuries among the study population was 13.2%. Toy manufacturing, animal husbandry, automobile manufacturing, shoe manufacturing, and biopharmaceutical manufacturing had the highest wrist injury rates at 29.1, 19.1, 14.9, 14.9, and 14.0%, respectively. Among the types of jobs, enamel workers (63.0%), butchers (43.6%), combers (32.5%), welders (31.3%), and scaffolders (26.5%) had the highest prevalence rates. Based on the final multivariate logistic regression analysis: female [odds ratios (OR) = 1.24; 95% confidence interval (CI), 1.15-1.35], 6-10 years of service (OR = 1.11; 95% CI, 1.03-1.18), >10 years of service (OR = 1.15; 95% CI, 1.06-1.25), frequent upward and downward flexion in wrist posture at work (OR = 1.81; 95% CI, 1.84-2.11), and frequent wrist placement on the edge of angular objects increased the OR of injury (OR = 1.52; 95% CI, 1.44-1.61). Need to squeeze objects tightly while working (OR = 1.72; 95% CI, 1.57-1.89), prolonged wrist flexion (OR = 1.86; 95% CI, 1.75-1.97), and work hand position above the shoulder for prolonged periods (OR = 1.11; 95% CI, 1.04-1.19) also suggested the relationship between these factors and the higher prevalence of wrist injury in the workers. The associated factor was physical activity (OR = 0.86; 95% CI, 0.80-0.94).

Conclusion

This study suggested the relationship between these factors and the higher prevalence of wrist injury in the toy manufacturing, animal husbandry, automobile manufacturing, and shoe-making industries, enamel workers, butchers, and combers. And are work types that require special attention. Females, working age, physical activity, and abnormal posture of the wrist were factors significantly associated with WMSDs.

Prevalence of Musculoskeletal Disorders and Their Associated Risk Factors among Furniture Manufacturing Workers in Guangdong, China: A Cross-Sectional Study

OBJECTIVE

This study aims to investigate the one-year prevalence and the associated factors of work-related musculoskeletal disorders (WMSDs) among furniture manufacturing workers in Guangdong, China.

METHODS

A cross-sectional study of 4181 (2953 males and 1228 females) furniture manufacturing workers was conducted between September 2019 and December 2019. All information about WMSDs was collected by the electronic version of Chinese Musculoskeletal Questionnaires (CMQ). Descriptive statistics and a binary logistic regression model were used to interpret the data.

RESULT

The overall prevalence of WMSDs was 31.57%. The WMSD symptoms most commonly occurred in the neck (16.77%), followed by the shoulders (14.90%), ankles/feet (14.64%), hands/wrists (13.30%), upper back (11.48%), and lower back (10.95%). Multiple logistic regression analysis revealed that several individual, labor organization, and ergonomics-related factors conferred significant risks to WMSDs at different body sites.

CONCLUSIONS

WMSDs remain the major occupational health problem for furniture manufacturing workers. Hence, some effective and feasible protective measures for furniture manufacturing workers are required in order to alleviate the health burden caused by WMSDs.

Derived patterns of musculoskeletal symptoms and their relationships with ergonomic factors among electronic assembly workers: A latent class analysis

INTRODUCTION

Multi-site musculoskeletal symptoms (MSS) are considered to be more common and have more serious consequences than single-site MSS. This study aimed to determine whether derived patterns of MSS may be identified in electronic assembly workers and if extracted MSS classes are associated with personal and work-related factors.

METHOD

A cross-sectional questionnaire study was performed with 700 participating electronic assembly workers. The questionnaire included individual factors, psychosocial and physical exposures, and MSS. The derived patterns of MSS and their relationships with ergonomic factors were analyzed using latent class analysis (LCA) and multinomial logistic regression models (MLRM).

RESULTS

The 1-year prevalence of MSS affecting only one body site or two or more body sites was 14.9% and 32.7%, respectively. The results of LCA showed three distinct classes of MSS patterns, which were labelled 'MSS in most sites' (5.0%), 'MSS in neck and shoulder' (27.0%), and 'MSS in one or no site' (68.0%). The results of MLRM showed that the 'MSS in neck and shoulder' was associated with job tenure (OR 5.579, 95% CI 2.488-12.511), excessive dynamic and static loads (OR 3.868, 95% CI 1.702-8.793 and OR 5.270, 95% CI 2.020-13.747, respectively); while the 'MSS in most sites' was associated with high job demands (OR 4.528, 95% CI 1.647-12.445) and excessive dynamic loads (OR 111.554, 95% CI 4.996-2490.793).

CONCLUSIONS

The results showed unique patterns of MSS among electronic assembly workers that were associated with personal and work-related factors.

PRACTICAL APPLICATIONS

The findings highlight that the high prevalence of multi-site MSS in this group should be a focus. It also provides further evidence that LCA considering the number and location of anatomical sites involving MSS can be used to determine distinct classes of MSS patterns, which is of great significance for the epidemiological study and management of MSS in the future.

Assessment of the influence of psychosocial factors on musculoskeletal disorder symptom intensity

BACKGROUND

Previous studies have observed that psychosocial factors are associated with an increase in work-related musculoskeletal disorders (WMSDs) in European countries. However, the influence of psychosocial factors on the WMSD symptoms has not been studied in detail. Additionally, working conditions differ between developing and developed countries.

OBJECTIVE

In this study, the influence of psychosocial factors on WMSD symptoms among men and women in the footwear industry in northeastern Brazil is investigated.

METHODS

A questionnaire survey was conducted to evaluate workers' perceptions of psychosocial factors and WMSD symptoms. The influence of psychosocial factors on WMSD symptom trends was observed through ordinal logistic regression models.

RESULTS

It was found that different psychosocial factors are related to WMSD symptom intensification. Factors such as "job insecurity" and "low social support," which are not associated with the worsening of WMSD symptoms in developed countries, showed a noticeable influence in the sample analyzed.

CONCLUSION

These findings may be associated with differences in working conditions and economic problems in developing countries, suggesting that some psychosocial factors have a different effect on workers' perceptions in developing countries.

Evaluation of work-related musculoskeletal disorders among sonographers in general hospitals in Guangdong province, China

Introduction. Research on the prevalence of and potential risk factors associated with work-related musculoskeletal disorders (WMSDs) among sonographers in China is scarce. More evidence is required to mitigate WMSDs among sonographers in Guangdong province, China. Objective. The present study aimed to determine the prevalence of and potential associated factors for WMSDs among sonographers in general hospitals in Guangdong province, China. Methods. A self-reported questionnaire was distributed to sonographers from 14 general hospitals selected by convenience sampling in Guangdong province. Multivariate logistic regression was used to analyze associations between potential factors and WMSDs in the most affected body areas. Results. In this study, 249 sonographers completed the questionnaire, yielding a response rate of 75.5%. The 12-month period prevalence of WMSDs was 95.2%, and the four most affected regions were the right shoulder (81.1%) followed by the neck (74.7%), right wrist/hand (59.4%) and lower back (57.0%). Among symptomatic sonographers, 31.2% were absent from work. Gender, years of experience, number of patients per day, shift type and lumbar support were associated with WMSDs in the most affected regions. Conclusion. Lower workload, more regular rest breaks and good ergonomics of working conditions are encouraged to alleviate WMSDs among sonographers in Guangdong province.

Low back pain in emergency ambulance workers in tertiary hospitals in China and its risk factors among ambulance nurses: a cross-sectional study

OBJECTIVE

Low back pain (LBP) could cause serious consequences and has been shown to be prevalent among emergency ambulance workers. Studies on the prevalence of and risk factors for LBP among emergency ambulance workers are scarce in China. The study aimed to determine the prevalence of LBP among ambulance workers, including doctors, nurses and drivers, and to explore the risk factors for ambulance nurses' chronic LBP (lasting for at least 3 months).

DESIGN

Cross-sectional study.

SETTING

Emergency ambulance systems from 38 tertiary hospitals in Shandong, China were selected by random cluster sampling.

PARTICIPANTS

A total of 1560 ambulance workers completed the study.

OUTCOME MEASURES

A paper-based questionnaire that included the Nordic Musculoskeletal Questionnaire, which evaluated LBP, the Dutch Musculoskeletal Questionnaire, which assessed ergonomic factors, and the Job Content Questionnaire, which assessed stress, was used. Multivariate logistic regression analysis was conducted to quantify the association of potential risk factors with chronic LBP among ambulance nurses.

RESULTS

The 1 year prevalence of LBP lasting for at least 24 hours, 7 days and 3 months was 86.1%, 50.6% and 21.1%, respectively, among 498 ambulance nurses; 70.5%, 36.4% and 15.8% among 519 doctors; and 57.5%, 23.8% and 12.3% among 543 drivers. The factors contributing to chronic LBP among ambulance nurses were the frequent bending of the trunk, heavy or awkward lifting, shift work, low job satisfaction, high psychological fatigue, high psychological job demand, low job control, low supervisor support, older age, female sex and obesity.

CONCLUSIONS

LBP was more prevalent among ambulance nurses than among ambulance doctors and drivers. Many factors, especially psychosocial and ergonomic factors, contributed to ambulance nurses' chronic LBP. Comprehensive measures might be needed to control LBP.

Prevalence and associated factors of musculoskeletal disorders among Chinese healthcare professionals working in tertiary hospitals: a cross-sectional study

BACKGROUND

Musculoskeletal disorders (MSDs) are prevalent in working populations and could result in a number of detrimental consequences. In China, healthcare professionals (HCP) in large hospitals may be likely to suffer from MSDs considering the facts of shortages in medical staff, the large Chinese population base, the aging of the population and patients' inclination to go to large hospitals. This study aimed to determine the prevalence and factors associated with MSDs among HCP working in tertiary hospitals.

METHODS

A self-administered questionnaire incorporating the Nordic Musculoskeletal Questionnaire and the Dutch Musculoskeletal Questionnaire was conducted among 14,720 HCP in eight tertiary hospitals selected by random cluster sampling in Shandong, China. Multivariable logistic regression analysis was used to quantify the association of psychological, ergonomic, organizational and individual factors with MSDs.

RESULTS

The 12-month period prevalence rate of experiencing an MSD in at least one body region for at least 24 h, experiencing an MSD for at least three months, and seeking health care for this condition were 91.2, 17.1 and 68.3%, respectively; these rates were highest for the lower back (72.8, 14.3, 60.3%) and knees (65.7, 8.1, 46.7%), followed by the shoulders (52.1, 6.2, 38.9%), neck (47.6, 4.8, 32.6%), wrists/hands (31.1, 3.2, 23.1%), ankles/feet (23.6, 1.9, 13.4%), upper back, hips/thighs and elbows. MSDs were associated with workload (work hours per week, break times during workday), psychological factors (psychological fatigue, mental stress), employment status and ergonomic factors. Regarding the ergonomic factors, lower back MSDs were associated with bending the trunk frequently, heavy or awkward lifting, and bending or twisting the neck; knee MSDs were associated with walking or standing for long periods of time; and shoulder MSDs were associated with maintaining shoulder abduction for long periods of time and bending or twisting the neck.

CONCLUSIONS

MSDs among HCP in tertiary hospitals in Mainland China were highly prevalent. The many factors listed above should be considered in the prevention of MSDs in HCP.

Prevalence of musculoskeletal symptoms among industrial employees in a modern industrial region in Beijing, China

BACKGROUND

Growing industrialization of China exposes its labor population to the risk of musculoskeletal disorders (MSDs). This study aimed to investigate the prevalence and risk factors of MSDs in a modern industrial region of Beijing.

METHODS

A cross-sectional study included 1415 employees in six industrial companies was conducted between January 2018 and May 2018 in Fangshan district, Beijng, China. Nordic Musculoskeletal Questionnaire (NMQ) was used to collect the information about MSDs. Demographic factors, lifestyle factors, health and medical factors, and work-related factors were collected as independent variables. Descriptive statistics, the chi-squared (χ) test, and binary logistic regression analysis were used to analyze data.

RESULTS

Among 1415 participants, 498 reported MSDs. The regions involved were the neck (25.16%), shoulders (17.17%), and upper back (13.29%). There was a significant statistical difference between frontline industrial workers and other staff in the prevalence of self-reported symptoms involving the shoulders (χ = 4.33, P = 0.037), wrists and hands (χ = 8.90, P = 0.003), and ankles and feet (χ = 12.88, P < 0.001). Increased age (P = 0.005, OR = 1.63; P = 0.001, OR = 2.33), a high or a low salary (P < 0.001, OR = 0.49; P < 0.001, OR = 0.30), night-shift (P = 0.027, OR = 1.46), two-week-history of illness and treatment (P = 0.004, OR = 5.60; P = 0.013, OR = 4.19), concurrent chronic diseases (P = 0.001, OR = 3.45; P = 0.092, OR = 7.81), limited access to health information (P = 0.004, OR = 0.49), and negative attitude towards seeking healthcare (P = 0.010, OR = 1.77; P = 0.009, OR = 2.75) were associated with MSDs in frontline workers. Female gender (P < 0.001, OR = 2.30), high education (P = 0.001, OR = 1.96), no exercises (P = 0.027, OR = 0.59), night-shift (P = 0.017, OR = 1.98), concurrent chronic diseases (P = 0.002, OR = 3.73; P = 0.020, OR = 13.42), limited access to health information (P = 0.013, OR = 0.53), far distance to medical institution (P = 0.009, OR = 1.83), and negative propensity (P = 0.009, OR = 1.94; P = 0.014, OR = 2.74) were associated with MSDs in other staffs.

CONCLUSIONS

The prevalence of MSDs among industrial employees has changed. Frontline workers had different prevalence and risk factors for MSDs compared with other employees. Negative propensity to healthcare, limited ways to obtain health knowledge, and concomitant chronic diseases were associated with MSDs. Surprisingly, highly educated and high-income employees had a higher risk of MSDs.

Knee musculoskeletal impairments and associated pain factors among rice farmers

BACKGROUND

Rice farming is done using manual methods and involves strenuous labour, which can lead to musculoskeletal disorders.

OBJECTIVE

To identify the factors associated with knee musculoskeletal impairments and related pain among rice farmers complaining of knee pain.

METHODS

The study employed a community-based, cross-sectional design. Full-time rice farmers (n= 201) were surveyed. A questionnaire was used to record demographics and details of farm work; followed by a physical examination of knee structures impairments.

RESULTS

The prevalence of knee impairment was highest among farmers with joint dysfunction (79.6%), followed by those with dysfunctional hamstring muscles (52.74%), quadriceps muscles (44.28%), neural tissue (38.81%), and ligaments (1.99%). It was lowest among farmers with meniscus dysfunction (1.49%). Stooping with twisting was strongly associated with knee joint and quadricep muscle impairment. Stooping with twisting and carrying loads were associated with hamstring muscle impairment. Stooping while twisting and being overweight was associated with neural tissue impairment. Being overweight was significantly associated with ligament impairment. There were no factors significantly associated with meniscus dysfunction.

CONCLUSIONS

Knee musculoskeletal impairments is common among Thai rice farmers. Joint dysfunction was common. The factors associated with knee musculoskeletal impairments included being overweight, stooping while twisting and carrying heavy weight.

Satisfaction with life and the risk of occupational injury

Background

Occupational injuries increase burden on society as well as personal health. Low satisfaction with life may not only increases the risk of occupational injuries directly, but also influences other factors that increase the risk of occupational injury. Along with previous studies on the risk of occupational injury, we sought to explore the relationship between satisfaction with life and occupational injury.

Methods

The study participants were 6234workers health screened at a university hospital in Incheon. Information on occupational injury and satisfaction with life scale (SWLS) was obtained in a self-report format. Participants were allocated to one of four SWLS groups; the dissatisfied group, the slightly dissatisfied group, the slightly satisfied group, and the satisfied group. The analysis was performed using the chi-square test primarily and by logistic regression adjusted for potential confounders.

Results

In men, the un-adjusted and adjusted odds ratios (ORs) of low satisfaction with life (SWLS< 20) were 1.98(CI1.55-2.53) and 1.81(CI 1.41-2.32), respectively. When the SWLS were divided into four groups, the adjusted ORs of the slightly satisfied (20-25), slightly dissatisfied(15-19), and dissatisfied(≤14) groups were 1.21, 1.72, and 2.70, respectively. That is ORs tended to increase linearly with decreasing SWLS score (p for trend < 0.001). In women, this relation was of borderline significance at best.When subjects were dichotomized based on SWLS scores, for males, the cured and adjusted RRs of occupational injury in the low satisfaction with life group were1.91 (95% CI: 1.50-2.42) and 1.66 (95% CI: 1.30-2.13), and for females, the adjusted-RR was marginally significant (1.67; 95% CI: 0.93-2.99).When subjects were divided into four groups by SWLS scores, adjusted RRs tended to increase linearly with decreasing SWLS score for males (slightly satisfied: 1.18, 95% CI: 0.77-1.82; slightly dissatisfied: 1.65, 95% CI: 1.08-2.52; dissatisfied: 2.22, 95% CI: 1.44-3.42; p for trend < 0.001) and for females (slightly satisfied: 1.17, 95% CI: 0.42-3.30; slightly dissatisfied: 1.56, 95% CI: 0.56-4.36; dissatisfied: 2.38, 95% CI: 0.84-6.74; p for trend = 0.040).

Conclusions

This study suggests that the risk of occupational injury was higher in workers not satisfied with life, and indicates attention to satisfaction with life may promote the health of workers.

Identification of influential demographic and work-related risk factors associated to lower extremity pain perception among rice farmers

BACKGROUND

A high prevalence of musculoskeletal disorders and abnormal alignments of the lower extremities (LE) was found for rice farmers. It is important to investigate demographic and work-related risk factors associated with LE pain prior to developing intervention strategies addressing the problematic factors of the highest-risk task.

OBJECTIVE

To identify factors associated with LE pain in rice farmers for every stage of the cultivation process.

METHODS

Thirty experienced farmers (age of 45.9±6.21 (mean±SD)) rated LE pain experienced before and after each cultivation stage using the Standardized Nordic Questionnaire. Risk factors of pain were characterized based on expert risk assessment of tasks due to force, posture and motion, in addition to a conventional survey of demographic and other work-related information.

RESULTS

Ergonomic risk factors were found to be the strongest predictors of knee and foot pain perception, which induced a substantial increase of pain perception (up to 4.6 times) with varying extent for individual cultivation stages. The highest risk and pain perception was found during the planting performance. Age exhibited significantly positive association with foot pain during planting and harvesting. However, more experienced farmers perceived less foot pain, presumably by developing effective movement strategies.

CONCLUSIONS

The findings suggest that the planting process should be subject of further intervention development, especially for older farmers, with focus on reducing force, awkward posture and repetitive movement to minimize risk of LE pain.

Association between psychosocial job characteristics and sickness absence due to low back symptoms using combined DCS and ERI models

OBJECTIVE

To evaluate the combined demand-control-support (DCS) and effort-reward-overcommitment (ERI-OC) stress models in association with sickness absence due to low back symptoms (SA-LBS).

METHODS

A total of 2,737 blue-collar workers recruited from 13 companies in the most populous province (Henan) of China were included in the study. Personal and physical job characteristics, psychosocial scales of the stress models, and SA-LBS data in the preceding year were collected by a self-reported questionnaire and analyzed by a multivariable logistic regression model. Tertile exposure levels (low, medium and high) were constructed to discriminate a risk level. Odds ratios (OR) with 95% confidence intervals (CI) were used as the association with SA-LBS.

RESULTS

A large percentage (84.5%) of the Chinese workers did not take sick leave after reporting low back symptoms during the preceding year. High job demand or medium-high reward was associated with SA-LBS. The association of the combined stress models and SA-LBS was not evident.

CONCLUSIONS

The ERI-OC model appeared to be more predictive of SA-LBS than the DCS model in the study population. The advantage of using combined stress models for predicting SA-LBS is not evident.

The Prevalence of and Risk Factors Associated with Musculoskeletal Disorders among Sonographers in Central China: A Cross-Sectional Study

Objective

Studies from industrialized countries show that musculoskeletal disorders (MSD) occur commonly in sonographers. However, little is known about sonographers in China, where the awareness of ergonomics and MSD, workload, and available equipment/facilities may differ. We aimed to investigate the prevalence of MSD and associated risk factors in sonographers in central China.

Methods

A cross-sectional survey was conducted with 381 sonographers from 14 randomly selected tertiary hospitals in Hubei province, central China. Musculoskeletal symptoms (using the Nordic Questionnaire) and risk factors (mostly derived from the Health Benefit Trust survey instrument and the Dutch Musculoskeletal Questionnaire) were recorded. Multivariate logistic regression was used to quantify associations between risk factors and MSD.

Results

The 12-month period prevalence of MSD was 98.3%, being highest in the neck (93.5%) and shoulder (92.2%), followed by the lower back (83.2%), wrist/hand, upper back, and elbow. Factors contributing to neck pain were psychological fatigue, shoulder abduction and trunk bend-and-twist posture. Height-adjustable tables and chairs were protective factors. Shoulder pain was associated with female sex, health status, mental stress, shoulder abduction, and trunk bend-and-twist posture. Height-adjustable chairs and the awareness of adjusting the workstation before scanning were protective factors. Elbow pain was associated with health status and height-adjustable tables. Wrist/hand pain was associated with female sex, bending the wrist, and working with obese patients. Upper back pain was associated with shoulder abduction, height-adjustable chairs, and device location. Lower back pain was associated with the number of scans performed per day, awkward postures, bending the trunk, twisting or bending the neck forward, and using a footrest.

Conclusions

This study suggests a high prevalence of MSD in sonographers in central China. Hence, it is necessary to improve the awareness of MSD by training, and the ergonomics of their current work environment by addressing physical workload, and psychological and equipment/facility-related factors.

Low Back Pain Prevalence and Related Workplace Psychosocial Risk Factors: A Study Using Data From the 2010 National Health Interview Survey

OBJECTIVES

The objectives of this study were to estimate prevalence of low back pain, to investigate associations between low back pain and a set of emerging workplace risk factors, and to identify worker groups with an increased vulnerability for low back pain in the United States.

METHODS

The data used for this cross-sectional study came from the 2010 National Health Interview Survey, which was designed to collect data on health conditions and related risk factors from the US civilian population. The variance estimation method was used to compute weighted data for prevalence of low back pain. Multivariable logistic regression analyses stratified by sex and age were performed to determine the odds ratios (ORs) and the 95% confidence interval (CI) for low back pain. The examined work-related psychosocial risk factors included work-family imbalance, exposure to a hostile work environment, and job insecurity. Work hours, occupation, and other work organizational factors (nonstandard work arrangements and alternative shifts) were also examined.

RESULTS

The prevalence of self-reported low back pain in the previous 3 months among workers in the United States was 25.7% in 2010. Female or older workers were at increased risk of experiencing low back pain. We found significant associations between low back pain and a set of psychosocial factors, including work-family imbalance (OR 1.27, CI 1.15-1.41), exposure to hostile work (OR 1.39, CI 1.25-1.55), and job insecurity (OR 1.44, CI 1.24-1.67), while controlling for demographic characteristics and other health-related factors. Older workers who had nonstandard work arrangements were more likely to report low back pain. Women who worked 41 to 45 hours per week and younger workers who worked >60 hours per week had an increased risk for low back pain. Workers from several occupation groups, including male health care practitioners, female and younger health care support workers, and female farming, fishing, and forestry workers, had an increased risk of low back pain.

CONCLUSIONS

This study linked low back pain to work-family imbalance, exposure to a hostile work environment, job insecurity, long work hours, and certain occupation groups. These factors should be considered by employers, policymakers, and health care practitioners who are concerned about the impact of low back pain in workers.

Variable Lifting Index for Manual-Lifting Risk Assessment: A Preliminary Validation Study

OBJECTIVE

The aim of this study was to evaluate the efficacy of the new Variable Lifting Index (VLI) method, theoretically based on the Revised National Institute for Occupational Safety and Health [NIOSH] Lifting Equation (RNLE), in predicting the risk of acute low-back pain (LBP) in the past 12 months.

BACKGROUND

A new risk variable termed the VLI for assessing variable manual lifting has been developed, but there has been no epidemiological study that evaluates the relationship between the VLI and LBP.

METHOD

A sample of 3,402 study participants from 16 companies in different industrial sectors was analyzed. Of the participants, 2,374 were in the risk exposure group involving manual materials handling (MMH), and 1,028 were in the control group without MMH. The VLI was calculated for each participant in the exposure group using a systematic approach. LBP information was collected by occupational physicians at the study sites. The risk of acute LBP was estimated by calculating the odds ratio (OR) between levels of the risk exposure and the control group using a logistic regression analysis. Both crude and adjusted ORs for body mass index, gender, and age were analyzed.

RESULTS

Both crude and adjusted ORs showed a dose-response relationship. As the levels of VLI increased, the risk of LBP increased. This risk relationship existed when VLI was greater than 1.

CONCLUSION

The VLI method can be used to assess the risk of acute LBP, although further studies are needed to confirm the outcome and to define better VLI categories.

Chinese cross-cultural adaptation and validation of the Oxford shoulder score

Background

The Oxford Shoulder Score (OSS) is a reliable and valid construct measuring non-specific shoulder pain, which are widely used to evaluate shoulder related quality of life. This study was to cross-culturally adapt and psychometrically validate a simplified Chinese version of the OSS (SC-OSS).

Methods

Cross-cultural adaptation was performed according to the international recognized guidelines. Consecutive patients with nonspecific shoulder pain were recruited to test the psychometric properties of SC-OSS. Item response trend and item-total correlation were evaluated to measure homogeneity. Principal component analysis (PCA) was used to evaluate the factorial structure. Cronbach's α and intra-class correlations were used to determine the reliability. Construct validity was analyzed by evaluating the correlations between SC-OSS and the Constant-Murley shoulder outcome score (CMSOS), the short form (36) health survey (SF-36) containing eight domains, and pain visual analogue scale (VAS).

Results

Overall, 121 patients were recruited. Each of the 12 items was properly responded and correlated with the total items. PCA extracted one factor for SC-OSS. SC-OSS had excellent reliability, with a Cronbach's α of 0.92 and intra-class correlation coefficient of 0.97 (95 % CI: 0.94-0.98). SC-OSS had a high correlation with CMSOS, physical functioning (PF) and bodily pain (BP) domains of SF-36 and VAS (r = -0.70, -0.65, -0.53, and -0.66, respectively). SC-OSS moderately correlated with role-physical (RP), social functioning (SF), general health perception (GH) and vitality (VT) (r = -0.45, -0.42, -0.39 and -0.36, respectively), but had a low correlation with role-emotional (RE) and mental health (MH) domains of SF-36 (r = -0.28 and -0.23, respectively).

Conclusions

SC-OSS demonstrated excellent acceptability, internal consistency, reliability and construct validity, which can be recommended for application in mainland China.

Prevalence and risk factor analysis of lower extremity abnormal alignment characteristics among rice farmers

BACKGROUND

Rice farming activities involve prolonged manual work and human-machine interaction. Prolonged farming risk-exposure may result in lower limb malalignment. This malalignment may increase the risk of lower extremity injury and physical disabilities. However, the prevalence and factors associated with lower extremity malalignment have not yet been reported. This study aimed to investigate the prevalence and risk factors of lower extremity malalignment among rice farmers.

METHODS

A cross-sectional survey was conducted with 249 rice farmers. Lower extremity alignment assessment included: pelvic tilt angle, limb length equality, femoral torsion, quadriceps (Q) angle, tibiofemoral angle, genu recurvatum, rearfoot angle, and medial longitudinal arch angle. Descriptive statistics were used to analyze participant characteristics and prevalence of lower extremity malalignment. Logistic regression analysis was used to identify risk factors.

RESULTS

The highest prevalence of lower extremity malalignment was foot pronation (36.14%), followed by the abnormal Q angle (34.94%), tibiofemoral angle (31.73%), pelvic tilt angle (30.52%), femoral antetorsion (28.11%), limb length inequality (22.49%), tibial torsion (21.29%), and genu recurvatum (11.24%). In females, the risk factors were abnormal Q angle, tibiofemoral angle, and genu recurvatum. Being overweight was a risk factor for abnormal pelvic tilt angle, Q angle, and tibiofemoral angle. Age was a risk factor for limb length inequality. Years of farming were a major risk factor for abnormal Q angle, tibiofemoral angle, and foot malalignment.

CONCLUSION

Prevalence of lower extremity malalignment was reported in this study. Female sex, being overweight, and years of farming were major risk factors for lower extremity malalignment. Lower extremity screening should assist in the identification of foot and knee malalignment in rice farmers. This may then lead to early prevention of musculoskeletal disorders arising from such malalignment.

Workplace psychosocial factors associated with work-related injury absence: a study from a nationally representative sample of Korean workers

BACKGROUND

Little is known about the association between psychosocial factors and injury absence in the workplace.

PURPOSE

This study aims to assess the association of comprehensive workplace psychosocial factors with work-related injury absence among Korean workers.

METHODS

The data (n = 7,856) were derived from the First Korean Working Conditions Survey conducted in 2006 with a representative sample (n = 10,043) of the Korean working population. The survey instrument contained questions about hours of work, physical risk factors, work organization, and the effect of work on health/injury. Work-related injury absence was indicated by a dichotomous variable with at least 1 day absence during the preceding 12 months. Logistic regression models were used to calculate odds ratio and confidence interval (CI). Incremental adjustments for sociodemographic, health behavior, and occupational confounding variables were employed in the models.

RESULTS

The overall 1-year prevalence of work-related injury absence in this study was 1.37 % (95 % CI, 1.11-1.63 %). Those who experienced violence at work (adjusted odds ratio (aOR), 7.05 (95 % CI, 2.69-18.5)), threat of violence at work (aOR, 4.25 (95 % CI, 1.32-13.64)), low job autonomy (aOR, 1.79 (95 % CI, 1.17-2.74)), and high job strain (aOR, 2.38 (95 % CI, 1.29-4.42) had an increased risk of injury absence, compared with their respective counterparts (p < 0.05). Among all job types, skilled workers in Korea were at a near fourfold risk of work absence due to occupational injuries, compared with managers in low-risk jobs.

CONCLUSION

Workplace violence and increased job strain were two key workplace psychosocial factors associated with work-related injury absence.

Job stress and work-related musculoskeletal symptoms among intensive care unit nurses: a comparison between job demand-control and effort-reward imbalance models

BACKGROUND

The aims of this study were to compare job demand-control (JDC) and effort-reward imbalance (ERI) models in examining the association of job stress with work-related musculoskeletal symptoms and to evaluate the utility of a combined model.

METHODS

This study analyzed cross-sectional survey data obtained from a nationwide random sample of 304 intensive-care unit (ICU) nurses. Demographic and job factors were controlled in the analyses using logistic regression.

RESULTS

Both JDC and ERI variables had strong and statistically significant associations with work-related musculoskeletal symptoms. Effort-reward imbalance had stronger associations than job strain or iso-strain with musculoskeletal symptoms. Effort-reward imbalance alone showed similar or stronger associations with musculoskeletal symptoms compared to combined variables of the JDC and ERI models.

CONCLUSIONS

The ERI model appears to capture the magnitude of the musculoskeletal health risk among nurses associated with job stress at least as well and possibly better than the JDC model. Our findings suggest that combining the two models provides little gain compared to using effort-reward imbalance only.