Prevalence of musculoskeletal symptoms among agricultural workers in the United States: an analysis of the National Health Interview Survey, 2004-2008

Evaluation of working conditions, work postures, musculoskeletal disorders and low back pain among sugar production workers

BACKGROUND: It is generally agreed that musculoskeletal disorders (MSDs) are a severe health concern, particularly for agricultural laborers. OBJECTIVES: The study aimed to identify risk factors and work-related disorders among agricultural workers at Amirkabir agro-industry company in Iran. METHOD: A total of 158 workers, of which 66 were manual harvesting workers (four postures), 40 were fertilizer transportation workers (three postures), and 52 were spraying workers (one posture), were included in the study. The research used questionnaires to collect data, and the postures were analyzed using 3DSSPP software. Related risk factors such as age, body mass index, work experience, working hours, and sports activity were analyzed. RESULTS: The incidence rate of lower back pain (94%), knee pain (82%), neck pain (69%), upper-back (63%), and shoulder (63%) were calculated. The logistic regression revealed that working hours and sports activities are significantly correlated to the wrist/hand and neck MSD with 5.62 and 6.38 times more likely among manual harvesting workers. The 3DSSPP software estimated that the lower back pain, especially in the first posture, for manure transportation workers was very high. Maximum L5-S1 compression, shear, and moment forces in the first posture among manure transportation workers were 7113 N and 472 N, -381 N-m, respectively. CONCLUSION: The 3DSSPP results also illustrated that compression, shear, and moment forces exceeded the NIOSH limit for the other postures. After interventions, compression, shear, and moment forces among all farm workers decreased. These findings emphasize that farm workers need to be under surveillance continuously at their workstations where interventions and improvement in specific tasks are required.

Factors Associated with Musculoskeletal Discomfort in Farmers and Ranchers in the U.S. Central States

Agricultural work involves ergonomic and psychosocial strain, which contribute to musculoskeletal conditions. The aim of this study was to assess if specific ergonomic, psychosocial, and preventive factors are linked to musculoskeletal pain or discomfort symptoms (MSS) in farmers and ranchers. We analyzed data from the Central States Center for Agricultural Safety and Health survey that was conducted in 2018 in a seven-state region of the central United States. MSS were assessed with questions from the Standardized Nordic Questionnaire. The survey included questions on demographic, ergonomic, psychosocial and preventive factors. Farm production variables were added from the Farm Market iD database. We analyzed the data using Generalized Estimating Equations. The overall prevalence of MSS for all body sites combined was 59% among 4,354 farmers and ranchers who responded (19% response rate). After controlling for age, sex, and operator status, three factors (high stress level, sleep deprivation, and exhaustion/fatigue) showed the strongest associations with MSS in any body site, with adjusted odds ratios (OR) ranging from 4.8 to 5.6. Forceful exertions, repetitive tasks, awkward postures, frequent manual labor, and vibration were also significantly associated with MSS, with adjusted ORs ranging from 1.8 to 3.3. Recommended preventive techniques were not protective for MSS. New effective strategies are needed to reduce the high burden of musculoskeletal outcomes among farmers and agricultural workers.

Gender differences in experience and reporting of acute symptoms among cleaning staff

BACKGROUND

Cleaning tasks pose risks of hazardous chemical exposure and adverse health effects for cleaning workers. We examined gender differences among cleaning staff in the experience of chemical-related symptoms and in reporting to supervisors.

METHODS

We analyzed cross-sectional reports from 171 university hospital or campus cleaning staff on chemical exposures to cleaning products, experience of acute symptoms, reporting of symptoms to supervisors, as well as demographic and psychosocial factors (risk perception, job demand/control, supervisor/co-worker support, and safety climate). Results were analized using multivariable logistic regression, adjusting for demographic, job, and psychosocial factors. Interactions of gender and psychosocial variables were also examined.

RESULTS

Men and women reported different frequencies for exposure-related tasks. Acute symptoms of chemical exposure were more prevalent in women compared with men (46.0% vs. 25.4%; adjusted odds ratio [OR] = 2.63; 95% confidence interval [CI] 1.27-5.46). Women were more concerned about exposure to cleaning chemicals (p = 0.029) but reported symptoms to their supervisor less often than men (18.5% vs. 40.6%, adjusted OR = 0.28; 95% CI 0.09-0.93). More supervisor support was significantly associated with less frequent symptom experience among women (OR = 0.83; 95% CI 0.70-0.99). Asian workers and less educated workers were less likely than others to report symptoms to supervisors. Gender differences in symptom reporting to supervisors were not explained by psychosocial factors.

CONCLUSIONS

Women may have increased susceptibility or perception of symptoms from cleaning compared to men, but this may be mitigated by supervisor support. Female Asian workers with lower education may perceive more significant barriers in reporting work-related symptoms to supervisors. Further research is needed to explore factors related to underreporting.

Biomechanical factors during common agricultural activities: Results of on-farm exposure assessments using direct measurement methods

Agricultural work is associated with increased risk of adverse musculoskeletal health outcomes. The purpose of this study was to quantify exposure to biomechanical factors among a sample (n = 55) of farmers in the Midwest region of the U.S. while they performed a variety of routine agricultural activities, and to compare exposure levels between these activities. Surface electromyography was used to estimate activity levels of the erector spinae, upper trapezius, forearm flexor, and forearm extensor muscle groups. Simultaneously, inertial sensors were used to measure kinematics of the trunk, upper arm, and wrist. In general, lower muscle activity levels, less extreme postures, and slower movement speeds were observed during activities that involved primarily the use of agricultural machinery in comparison to manual activities, suggesting a potential advantage of mechanization relative to musculoskeletal health. Median wrist movement speeds exceeding recently proposed exposure thresholds were also observed during many manual activities, such as milking animals and repairing equipment. Upper arm postures and movement speeds did not appear to confer excessive risk for shoulder-related outcomes (on the whole), but interpretation of the results is limited by a sampling approach that may not have captured the full extent of exposure variation. Not surprisingly, substantial variation in exposure levels were observed within each agricultural activity, which is related to substantial variation in the equipment, tools, and work practices used by participants. Ultimately, the results of this study contribute to an emerging literature in which the physical demands of routine agricultural work have been described on the basis of sensor-based measurements rather than more common self-report or observation-based approaches.

Work-related upper extremity musculoskeletal disorders in the United States: 2006, 2009, and 2014 National Health Interview Survey

BACKGROUND

The annual incidence rate of work-related upper extremity musculoskeletal disorders (WUEMSDs) is increasing in US workers according to the United States Bureau of Labor Statistics (BLS). However, the prevalence of WUEMSDs among US total workers has not been estimated.

OBJECTIVE

We aimed to estimate the prevalence of WUEMSDs among US total workers and among each of major occupations and industries.

METHODS

We analyzed data from the National Health Interview Survey Arthritis supplements (2006, 2009, and 2014) among 50,218 current workers (age ≥18 years) to estimate the 30-day prevalence of WUEMSDs and of WUEMSDs affecting work using the SAS-callable SUDAAN software.

RESULTS

About 11.2 million workers reported WUEMSDs based on three surveys (2006, 2009, and 2014). The 30-day prevalence of WUEMSDs was 8.23% the prevalence of WUEMSDs affecting work was 1.24%. The Construction occupation and industry had the highest age- and sex-adjusted 30-day prevalence of WUEMSDs (10.98% for Construction occupation; 9.94% for Construction industry) and WUEMSDs affecting work (3.32% for Construction occupation; 2.31% Construction industry).

CONCLUSIONS

Our results show that construction workers had the highest prevalence of both WUEMSDs and WUEMSDs affecting work. They may be a priority group for interventions to reduce upper extremity musculoskeletal disorders.

Immigrant Legal Status and Health: Legal Status Disparities in Chronic Conditions and Musculoskeletal Pain Among Mexican-Born Farm Workers in the United States

Immigrant legal status determines access to the rights and privileges of U.S. society. Legal status may be conceived of as a fundamental cause of health, producing a health disparity whereby unauthorized immigrants are disadvantaged relative to authorized immigrants, a perspective that is supported by research on legal status disparities in self-rated health and mental health. We conducted a systematic review of the literature on legal status disparities in physical health and examined whether a legal status disparity exists in chronic conditions and musculoskeletal pain among 17,462 Mexican-born immigrants employed as farm workers in the United States and surveyed in the National Agricultural Workers Survey between 2000 and 2015. We found that unauthorized, Mexican-born farm workers have a lower incidence of chronic conditions and lower prevalence of pain compared with authorized farm workers. Furthermore, we found a legal status gradient in health whereby naturalized U.S. citizens report the worst health, followed by legal permanent residents and unauthorized immigrants. Although inconsistent with fundamental cause theory, our results were robust to alternative specifications and consistent with a small body of existing research on legal status disparities in physical health. Although it is well known that Mexican immigrants have better-than-expected health outcomes given their social disadvantage, we suggest that an epidemiologic paradox may also apply to within-immigrant disparities by legal status. We offer several explanations for the counterintuitive result.

Frequent Exertion and Frequent Standing at Work, by Industry and Occupation Group - United States, 2015

Repeated exposure to occupational ergonomic hazards, such as frequent exertion (repetitive bending or twisting) and frequent standing, can lead to injuries, most commonly musculoskeletal disorders (1). Work-related musculoskeletal disorders have been estimated to cost the United States approximately $2.6 billion in annual direct and indirect costs (2). A recent literature review provided evidence that prolonged standing at work also leads to adverse health outcomes, such as back pain, physical fatigue, and muscle pain (3). To determine which industry and occupation groups currently have the highest prevalence rates of frequent exertion at work and frequent standing at work, CDC analyzed data from the 2015 National Health Interview Survey (NHIS) Occupational Health Supplement (OHS) regarding currently employed adults in the United States. By industry, the highest prevalence of both frequent exertion and frequent standing at work was among those in the agriculture, forestry, fishing, and hunting industry group (70.9%); by occupation, the highest prevalence was among those in the construction and extraction occupation group (76.9%). Large differences among industry and occupation groups were found with regard to these ergonomic hazards, suggesting a need for targeted interventions designed to reduce workplace exposure.

Optimizing implementation of interventions in agriculture for occupational upper extremity musculoskeletal disorders: Results of an expert panel

BACKGROUND

Upper extremity musculoskeletal disorders (UEMSD) is reported worldwide as the second-largest occupational musculoskeletal disorder in agriculture.

OBJECTIVE

The objective of the study is to identify facilitators and barriers for employers and workers for implementing interventions to reduce work-related risk factors associated with occupational UEMSD in the agricultural sector, according to health and safety consultants.

METHODS

An expert panel was used comprising nine health and safety consultants from the Dutch agricultural sector.

RESULTS

Facilitators and barriers for employers and workers were categorized in the following themes: knowledge, skills, attitude, culture, costs, loss of income, facilitation and employability. There were no differences in facilitators and barriers between UEMSD.

CONCLUSIONS

Facilitators and barriers for implementing preventive interventions in agriculture were on organizational level, like diversity in choice of preventive devices, and personal level such as willingness if there is no work disability.

Musculoskeletal pain, depression, and stress among Latino manual laborers in North Carolina

The jobs of Latino manual laborers place their mental and physical health at risk. This study evaluates the associations among musculoskeletal pain, mental health, and work organization in Latino manual laborers. Farmworkers and nonfarmworkers (n = 189) in North Carolina were interviewed for self-reported musculoskeletal pain, depressive symptoms, stress, work safety climate, and precarious job status. More nonfarmworkers than farmworkers had neck and shoulder pain, but they did not differ in other areas of musculoskeletal pain. Depressive symptoms had a significant association with neck and shoulder pain (p < .05). Precariousness had a significant association with back pain (p < .05). Farmworker participants had H-2A visas and were afforded some protection compared to nonfarmworker manual workers. Research is needed to improve policy that relieves pain and improves mental health for all Latino manual workers.

Effects of Zusanli and Ashi Acupoint Electroacupuncture on Repair of Skeletal Muscle and Neuromuscular Junction in a Rabbit Gastrocnemius Contusion Model

Objective. To explore the effects of electroacupuncture (EA) at ST36 (EA-ST36) and at Ashi acupoints (EA-Ashi) on skeletal muscle repair. Methods. Seventy-five rabbits were randomly divided into five groups: normal, contusion, EA-Ashi, EA-ST36, and EA at Ashi acupoints and ST36 (EA-AS). EA (0.4 mA, 2 Hz, 15 min) was applied after an acute gastrocnemius contusion. The morphology of myofibers and neuromuscular junctions (NMJs) and expressions of growth differentiation factor-8 (GDF-8), acetylcholinesterase (AChE), Neuregulin 1 (NGR1), and muscle-specific kinase (MuSK) were assessed 7, 14, and 28 days after contusion. Results. Compared with that in contusion group, there was an increase in the following respective parameters in treatment groups: the number and diameter of myofibers, the mean staining area, and continuities of NMJs. A comparison of EA-Ashi and EA-ST36 groups indicated that average myofiber diameter, mean staining area of NMJs, and expressions of AChE and NRG1 were higher in EA-Ashi group, whereas expression of GDF-8 decreased on day 7. However, increases in myofiber numbers, expressions of MuSK and AChE, as well as decreases in GDF-8 expression, and the discontinuities were observed in EA-ST36 group on the 28th day. Conclusion. Both EA-ST36 and EA-Ashi promoted myofiber regeneration and restoration of NMJs. EA-Ashi was more effective at earlier stages, whereas EA-ST36 played a more important role at later stages.