Musculoskeletal symptom survey among mason tenders

Adverse Health Effects and Perceived Musculoskeletal Pain in the Sawmill Workers of West Bengal, India

The present study aimed to determine the prevalence of musculoskeletal pain, unfavorable working conditions, and assessment of occupational injuries among sawmill workers. The Nordic Musculoskeletal Questionnaire, measurement of handgrip strength, working environment, and occupational injuries were assessed among 135 sawmill workers participating in the study. The data showed that sawmill workers complained of discomfort (pain) felt primarily in the low back region of the body followed by the shoulders, hands, knees, upper back, and wrist. This study indicated that sawmill workers had less handgrip strength due to more intense manual work than control subjects. Based on the results of this study, it was concluded that sawmill workers were highly affected due to working in an awkward posture with manual material handling for an extended period of time and that these factors may lead to work-related musculoskeletal disorders as well as occupational injuries. Proper training, a proper work-rest schedule, and modifications of some working procedures may reduce injuries and work-related musculoskeletal pain.

A science mapping-based review of work-related musculoskeletal disorders among construction workers

INTRODUCTION

Work-related musculoskeletal disorders (WMSDs) are recognized as a leading cause of nonfatal injuries in construction, but no review of existing studies has systematically analyzed and visualized the trends of WMSDs among construction workers. The current science mapping-based review summarized research published between 2000 and 2021 related to WMSDs among construction workers through co-word, co-author, and citation analysis.

METHOD

A total of 63 bibliographic records retrieved from the Scopus database were analyzed.

RESULTS

The results identified influential authors with high impacts in this research domain. Moreover, the results indicated that MSDs, ergonomics, and construction not only had the highest occurrence of been studied, but also the highest impact in terms of total link strength. In addition, the most significant contributions to research relating to WMSDs among construction workers have originated primarily from the United States, Hong Kong, and Canada. Furthermore, a follow-up in-depth qualitative discussion was conducted to focus on summarizing mainstream research topics, identifying existing research gaps, and proposing directions for future studies.

CONCLUSIONS

This review provides an in-depth understanding of related research on WMSDs among construction workers and proposes the emerging trends in this research field.

Effects of working posture, lifting load, and standing surface on postural instability during simulated lifting tasks in construction

Postural instability is a major contributor to fatal and nonfatal falls in the construction industry. This study investigated the effects of working posture, lifting load and standing surface on perceived postural instability. Thirty young males performed simulated lifting tasks in construction using six different postures under four experimental conditions (2 loads × 2 surfaces). Results showed working postures with bending at the waist and overhead carrying were associated with high postural instability. With lifting load and inclined standing surface both significantly increased postural instability for all working postures except the full squatting. Full squatting with lifting load was more stable than without load for the flat surface, but opposite for the inclined surface. These findings indicate three investigated factors had not only significant main effects, but also complicated interaction effects on postural instability, implying that all three factors should be considered simultaneously for the real practice on fall prevention in construction. Practitioner summary: The leading causes of worker deaths in the construction industry were falls. This study showed that working postures with waist bending and overhead carrying were associated with high postural instability. With lifting load and inclined standing surface both significantly increased postural instability for all working postures except the full squatting.

Effects of ground and load on upper trapezius, biceps brachii muscle and hand forces in one- and two-wheeled wheelbarrow pushing

This study examines the effects of ground surface, load, one- and two-wheeled wheelbarrow on muscular activities, hand force, and subject-perceived exertions while pushing a wheelbarrow in a straight line on a horizontal surface. The experimental results show that wheelbarrow load significantly affected muscular activities, hand force, and subject-perceived exertion. Additionally, different ground surfaces and wheelbarrow types also affected the muscular activities of the dominant hand; grass generated the highest muscle load and asphalt pavement generated the smallest muscle load. The user has to apply 57% and 23% more force in the vertical and horizontal direction while pushing one-vs. two-wheeled wheelbarrow. Muscular activity increased significantly in the dominant hand with the one-wheeled wheelbarrow compared with the two-wheeled wheelbarrow, suggesting that, in terms of muscle loads, the two-wheeled wheelbarrow is better than the one-wheeled wheelbarrow.

Ergonomic intervention to reduce musculoskeletal disorders among flour factory workers

BACKGROUND

Work-related musculoskeletal disorders are the most common occupational health hazards. In the flour production industry, the fast pace of work, high frequency of repetitive movements, manual handling of loads, and awkward postures put a lot of pressure on the worker's body.

OBJECTIVE

Given the high exposure of the workers of the flour production industry to ergonomic risk factors, this study aimed to reduce the rate of musculoskeletal disorders among a group of flour factory workers through ergonomic interventions.

MATERIALS AND METHODS

This interventional study was performed using the census method on the eligible workers of a flour factory. An ergonomic intervention program was planned and implemented with the goal of reducing musculoskeletal disorders. The effectiveness of the program was evaluated by measuring the prevalence of musculoskeletal disorders before and six months after the interventions.

RESULTS

Before the intervention, musculoskeletal disorders were most prevalent in the lower back, arms, shoulders, legs, thighs, knees, neck and wrists, respectively. Evaluation of the prevalence of musculoskeletal disorders after the intervention showed the positive effect of the ergonomic intervention program on musculoskeletal disorders in the neck, shoulders, lower back, thighs, knees, and legs (P < 0.05).

CONCLUSION

Engineering and management interventions implemented in this study led to a significant reduction in the level of ergonomic risk factors and a reduced rate of musculoskeletal disorders among workers of different units in the flour factory.

Prevalence of work-related musculoskeletal pain in masonry apprentices

The construction industry, specifically masonry, reports more work-related musculoskeletal disorders (WMSD) rates than the general industry. Masonry apprentices are assumed to be healthy, yet may have WMSDs. The purpose of this study was to evaluate the prevalence of musculoskeletal symptoms (MSS), time loss, and healthcare use among apprentices. 183 brick and block masonry apprentices completed surveys on demographics, work history, MSS, and functional well-being. The prevalence of MSS was calculated by body region, time loss, and healthcare use. The relationship between MSS, and perceived global physical and mental health was assessed. Approximately 78% of apprentices reported MSS, most in several body regions. Low back and wrists/hands were most prevalent, although few missed work or sought healthcare. Lower functional health and well-being was reported. Apprentices reported MSS comparable to previous studies of journey-level masons. Apprenticeship programmes could integrate ergonomics education to help apprentices develop safety culture early in their careers. Practitioner Summary: New masonry workers (apprentices) are assumed to be healthy yet work-related musculoskeletal symptoms (MSS) may be common early in their career. The prevalence of MSS was assessed among apprentices. Approximately 78% of apprentices reported MSS, most in several body regions, comparable to journey-level masons. Abbreviations: WMSD: work-related musculoskeletal disorders; MSS: musculoskeletal symptoms; SAVE: SAfety voice for ergonomics; MNQ: modified nordic questionnaire; FTE: full-time equivalent; SF-12: short from-12v2.

Perception of dental students on risk factors of musculoskeletal disorders

OBJECTIVE

To evaluate the validity and reliability of the Job Factors Questionnaire, and the influence of gender, academic level and pain/discomfort on dental students' perception regarding risk factors of musculoskeletal disorders.

METHODS

One hundred forty-five dental students from Stony Brook School of Dental Medicine participated voluntarily in this study. The survey was organised in two sections: (i) Job Factors Questionnaire with 15 items that evaluated students' perceptions about job/study environmental risk factors and their potential contribution to musculoskeletal disorders. The tri-factorial structure (repetitiveness, work posture and external factors) was used; (ii) Part of the Nordic Questionnaire with questions referring to 9 body areas: Neck, shoulders, upper back, elbows, lower back, wrists/hands, hips, knees and ankles/feet. Students answered if they have had a job-related pain/discomfort in any of these body areas in the previous 12 months. The data were evaluated statistically by confirmatory factor analysis, convergent and discriminant validities, internal consistency and Z-test (α = .05).

RESULTS

The tri-factorial structure was considered valid and reliable for the sample after excluding item 8 and inserting correlations between items 11 and 12, and between 14 and 15. The academic level presented a significant effect on the factors "Work Posture" (P = .02) and "External Factors" (P = .01). Most of the students reported pain in their neck (73.79%), lower back (62.06%) and shoulders (53.10%) in the previous 12 months.

CONCLUSION

The Work Posture and External Factors were influenced only by academic level. The lower the students' academic level, the higher their perception for both factors of musculoskeletal disorders.

The prevalence of musculoskeletal symptoms in the construction industry: a systematic review and meta-analysis

PURPOSE

Although individual studies have reported high prevalence of musculoskeletal symptoms (MSS) among construction workers, no systematic review has summarized their prevalence rates. Accordingly, this systematic review/meta-analysis aimed to synthesize MSS prevalence in different construction trades, gender and age groups, which may help develop specific ergonomic interventions.

METHODS

Nine databases were searched for articles related to the research objective. Two reviewers independently screened citations, extracted information and conducted quality assessment of the included studies. Meta-analyses were conducted on clinical and statistical homogenous data.

RESULTS

Thirty-five out of 1130 potential citations were included reporting diverse types of period prevalence and case definitions. Only the 1-year prevalence rates of MSS (defined as at least one episode of pain/MSS in the last year) at nine anatomical regions had sufficient homogeneous data for meta-analysis. Specifically, the 1-year prevalence of MSS was 51.1% for lower back, 37.2% for knee, 32.4% for shoulder, 30.4% for wrist, 24.4% for neck, 24.0% for ankle/foot, 20.3% for elbow, 19.8% for upper back, and 15.1% for hip/thigh. Female workers demonstrated a higher prevalence of MSS while there was insufficient information on the prevalence of trade-specific or age-related MSS. The quality assessments revealed that many included studies estimated prevalence solely based on self-reported data, and did not report non-respondents' characteristics.

CONCLUSIONS

Lumbar, knee, shoulder, and wrist MSS are the most common symptoms among construction workers. Future studies should standardize the reporting of period prevalence of MSS in different construction trades to allow meta-analyses and to develop relevant MSS prevention program.

Combined effect of low back muscle fatigue and passive tissue elongation on the flexion-relaxation response

Previous literature has documented the alterations in the flexion-relaxation response of the lumbar extensor musculature to passive tissue elongation (PTE) and muscle fatigue (MF). There is no study, however, that has explored this response as a function of the combined effect of both PTE and MF, which is often seen in occupational settings. Twelve participants performed three experimental protocols on three different days to achieve (1) PTE, (2) MF and (3) PTE&MF (combined). Trunk kinematics and muscle activities were monitored to assess the effects of these protocols on the peak lumbar flexion angle and the lumbar angle of the flexion-relaxation of the trunk extensor muscles. Results showed responses to the uni-dimensional stresses (PTE and MF) consistent with those seen in the previous literature, while the combined protocol elicited responses that more closely matched the PTE protocol.

Prevalence of musculoskeletal pain in construction workers in Saudi Arabia

The objective of this study was to find out the prevalence, characteristics, and distribution of musculoskeletal pain among construction workers in Saudi Arabia. A questionnaire about musculoskeletal pain in different parts of the body was completed by 165 construction workers from the construction industries in Dammam and Riyadh cities. The descriptive data were analyzed using chi-square test. The level of statistical significance was set at P < 0.05. Eighty (48.5%) of the responding workers had pain in neck, shoulders, lower back, hand, knee, or ankle. The majority of respondents had low back pain (50%) followed by knee pain (20%). The average intensity of pain at all sites during activity and rest was 6.65 and 3.59, respectively. Thirty-four (42.5%) respondents had dull aching pain and 24 (30%) had cramping pain. There was an association between years of experience, duration of break during work, and use of protective equipment with the prevalence of musculoskeletal pain in construction workers (P < 0.05). Most of the workers complaining of pain got medical treatment (62.5%) and only 25% received physical therapy. It can be concluded from this study that the prevalence of musculoskeletal pain among construction workers in Saudi Arabia is high.

Psychometric properties evaluation of a new ergonomics-related job factors questionnaire developed for nursing workers

The objectives of this study were to develop a questionnaire that evaluates the perception of nursing workers to job factors that may contribute to musculoskeletal symptoms, and to evaluate its psychometric properties. Internationally recommended methodology was followed: construction of domains, items and the instrument as a whole, content validity, and pre-test. Psychometric properties were evaluated among 370 nursing workers. Construct validity was analyzed by the factorial analysis, known-groups technique, and convergent validity. Reliability was assessed through internal consistency and stability. Results indicated satisfactory fit indices during confirmatory factor analysis, significant difference (p < 0.01) between the responses of nursing and office workers, and moderate correlations between the new questionnaire and Numeric Pain Scale, SF-36 and WRFQ. Cronbach's alpha was close to 0.90 and ICC values ranged from 0.64 to 0.76. Therefore, results indicated that the new questionnaire had good psychometric properties for use in studies involving nursing workers.

Musculoskeletal Disorders Among Thai Women in Construction-Related Work

A cross-sectional study was conducted to determine the prevalence of musculoskeletal disorder symptoms and its risk factors among women rebar workers. A simple random sampling method was used and data were collected by face-to-face interview and ergonomic assessment from February to March 2011. A total of 272 women rebar workers with at least 6 months’ job experience participated in this study. The findings revealed that 57.7% of workers reported musculoskeletal disorder symptoms with low back and shoulders as the most common body parts affected (46.0%). Multiple logistic regression analysis indicated 2 variables that are significantly associated with musculoskeletal disorders: prolonged working hours (adjusted odds ratio = 7.63; 95% confidence interval = 2.06-28.31) and awkward posture (adjusted odds ratio = 43.79; 95% confidence interval = 17.09-112.20). The high prevalence of musculoskeletal disorders among women rebar workers suggests that an appropriate ergonomic workstation design and ergonomic training for women rebar workers are necessary.

Individual participant data meta-analysis of mechanical workplace risk factors and low back pain

OBJECTIVES

We used individual participant data from multiple studies to conduct a comprehensive meta-analysis of mechanical exposures in the workplace and low back pain.

METHODS

We conducted a systematic literature search and contacted an author of each study to request their individual participant data. Because outcome definitions and exposure measures were not uniform across studies, we conducted 2 substudies: (1) to identify sets of outcome definitions that could be combined in a meta-analysis and (2) to develop methods to translate mechanical exposure onto a common metric. We used generalized estimating equation regression to analyze the data.

RESULTS

The odds ratios (ORs) for posture exposures ranged from 1.1 to 2.0. Force exposure ORs ranged from 1.4 to 2.1. The magnitudes of the ORs differed according to the definition of low back pain, and heterogeneity was associated with both study-level and individual-level characteristics.

CONCLUSIONS

We found small to moderate ORs for the association of mechanical exposures and low back pain, although the relationships were complex. The presence of individual-level OR modifiers in such an area can be best understood by conducting a meta-analysis of individual participant data.

Comparison of biomechanical loading during use of conventional stud welding equipment and an alternate system

We investigated the effect of an alternative welding system designed to reduce exposure to extreme trunk flexion on measures of trunk inclination and muscle activity. Among 10 participants, data were collected while using conventional stud welding equipment and while using the alternate system. Paired t-tests were used to compare results between the two welding systems. Mean trunk inclination angle was reduced with the alternate system (34.4° versus 9.7°, p < 0.01). Percent time with trunk inclination angles greater than 60° was also reduced (40.0% versus 4.7%, p < 0.01). In general, the alternate system resulted in less desirable upper trapezius muscle activity levels. The alternate system appears to be effective in reducing exposure to extreme trunk flexion among stud welders. Continued development of the system should explore features designed to reduce shoulder forces and improve productivity.

Physical ergonomic hazards in highway tunnel construction: overview from the Construction Occupational Health Program

This report provides an overview of physical ergonomic exposures in highway construction work across trades and major operations. For each operation, the observational method "PATH" (Posture, Activity, Tools and Handling) was used to estimate the percentage of time that workers spent in specific tasks and with exposure to awkward postures and load handling. The observations were carried out on 73 different days, typically for about 4 h per day, covering 120 construction workers in 5 different trades: laborers, carpenters, ironworkers, plasterers, and tilers. Non-neutral trunk postures (forward or sideways flexion or twisting) were frequently observed, representing over 40% of observations for all trades except laborers (28%). Kneeling and squatting were common in all operations, especially tiling and underground utility relocation work. Handling loads was frequent, especially for plasterers and tilers, with a range of load weights but most often under 15 pounds. The results of this study provide quantitative evidence that workers in highway tunnel construction operations are exposed to ergonomic factors known to present significant health hazards. Numerous opportunities exist for the development and implementation of ergonomic interventions to protect the health and safety of construction workers.

The estimated national burden of physical ergonomic hazards among US workers

PURPOSE

To estimate the national burden of physical ergonomic hazards among working adults in the US.

METHODS

We estimated the population prevalence of and the total number of workers who are exposed to physical ergonomic hazards, such as vibration, working in cramped space, kneeling, body bending or twisting, climbing, and repetitive motions using Occupational Information Network (O*NET) data and the Occupational Employment Statistics (OES) from the U.S. Bureau of Labor Statistics (BLS) stratified by occupation title.

RESULTS

Repetitive motion was the most prevalent of all ergonomic hazards (27% of US workers are estimated to be exposed continually). Bending or twisting of the body more than half their time at work was also common, involving over 32 million US workers (25% of US workforce). Kneeling, crouching, stooping, or crawling was another ergonomic hazard that 14 million US workers perform more than half their time at work. Almost 4 million workers climb ladders, scaffolds, poles, etc. for more than half their time at work. We estimate that over 13 million workers (10% of US workforce) were exposed to cramped workspace that requires getting into awkward positions every day. Finally, about 3.5 million workers (2.7% of US workforce) were estimated to be exposed to whole body vibration every day.

CONCLUSION

A large portion of the US work force is exposed to ergonomic hazards known to be associated with musculoskeletal disorders (MSDs). The occupations with the highest prevalence of each ergonomic hazard may be deserving of prompt efforts toward prevention of MSDs.

Investigating reduced bag weight as an effective risk mediator for mason tenders

Masonry workers face some of the highest physical demands in the construction industry where large bags of masonry material weighing 42.7 kg are commonly handled by mason tenders who mix the mortar, distribute mortar and bricks/blocks, and erect/dismantle scaffolding throughout the day. The objective of this study was to determine the effectiveness of using half-weight bags (21.4 kg) on reducing the biomechanical loading, physiological response, and perceived exertions. Ten male subjects performed asymmetric lifting tasks simulating unloading bags from a pallet. Muscle activity, trunk kinematics, heart rate, blood pressure and subjective rating data were collected. Spine loads were predicted from a well-validated EMG-assisted model. Bag weight, lift type, bag height at origin, and asymmetry at destination significantly impacted the spine loads. While there was a 50% reduction in bag weight, the peak loads for the half-weight bags were only 25% less than the more available full-weight bags (a reduction of about 320 N of shear and 1000 N of compression). Lifts allowing movement of the feet reduced the loads by about 22% in shear and 27% in compression compared to constrained postures. Interestingly, cumulative spine loads were greater for the lighter bags than the heavy bags ( approximately 40%). The subjective ratings of exertion and risk were significantly lower for the lighter bags. RELEVANCE TO INDUSTRY: The reduction in peak spine loading for the half-weight bags, particularly at the higher heights and when the feet were allowed to move could significantly reduce the injuries of masonry workers. However, there were trade-offs with cumulative loads that may minimize the reduced risk. Overall, given the limited amount of time lifting bags, the reduction of peak loads.

A multivariate analysis of factors associated with early offer and acceptance of a work accommodation following an occupational musculoskeletal injury

OBJECTIVE

To identify factors associated with offer and acceptance of work accommodation.

METHODS

In 401 claimants with musculoskeletal injuries, two logistic regressions identified individual and workplace factors associated with work accommodation offer and acceptance.

RESULTS

Unionized status, strong disability management policies and practices, low supervisor support, and pink collar occupation were associated with work accommodation offer. Job tenure over 1 year and lighter physical work were associated with acceptance. Younger age and more repetitive physical work demands were positively associated with both outcomes. Pink-collar status was positively associated with offers, but negatively with acceptance. Gender, mental health, pain, job satisfaction, firm size, people-oriented culture, safety climate, and ergonomic practices were not significant predictors.

CONCLUSIONS

One month post-injury, workplace factors and age are determinants of offer and acceptance of work accommodation, while individual health factors play no significant role.

Occupational safety: the role of workplace sleepiness

Workplace sleepiness refers to how sleepy a person feels at work, and it is thought to be associated with negative occupational safety outcomes such as injuries because sleepiness can lead to behavioral decrements at work. This study explored safety behavior as a mediator of the relationship between workplace sleepiness and occupational safety outcomes (e.g., occupational injuries). A survey was conducted on certified nursing assistants working in long term care facilities. The Stanford Sleepiness Scale was used to measure workplace sleepiness. Occupational injuries were assessed in multiple ways: injury frequency, injury severity, pain frequency, pain severity-duration, and pain severity-intensity. This study provided support for a negative relationship between workplace sleepiness and safety behavior and limited support for a positive relationship between workplace sleepiness and occupational injuries. Workplace sleepiness was significantly related to pain frequency and pain severity (as indexed by both duration and intensity); however, it was not significantly related to injury frequency or severity. The results of the study also suggest very limited support for safety behavior as a mediator of this relationship. The findings suggest that the relationship between workplace sleepiness and occupational injuries might be more complex than originally assumed.

Creep and fatigue development in the low back in static flexion

STUDY DESIGN

In vivo measurements of low back flexion posture and muscle activity before, during, and after static flexion.

OBJECTIVE

To identify the occurrence of creep and muscle fatigue development in the low back during static upper body deep flexion that resembled an above ground work posture.

SUMMARY OF BACKGROUND DATA

Static lumbar flexion has been related to the development of low back disorders, and its injury mechanism has been focused on the changes in passive spinal tissues. Potential influences of muscle fatigue of extensor muscles have not been explored.

METHODS

A total of 20 asymptomatic subjects performed submaximal isometric trunk extension exertions and an isokinetic trunk flexion before and immediately after 5-minute static flexion while the trunk sagittal flexion angle and the myoelectric activities (electromyography [EMG]) of back extensor muscles were recorded simultaneously. Changes in the flexion-relaxation onset angle, maximum flexion angle, muscle activity level, and the median power frequency of EMG associated with the static flexion were evaluated.

RESULTS

Flexion-relaxation onset angle in isokinetic flexion and EMG amplitude of isometric extension were significantly greater after static flexion, indicating creep of spinal tissues in static flexion. Median power frequency of lumbar erector spinae EMG during isometric extension was significantly lower after static flexion, suggesting the development of muscle fatigue. Consistent but low level of EMG was observed together with sporadic muscle spasms during the static flexion period.

CONCLUSION

Fatigue of low back extensor muscles may occur in static flexion due to prolonged passive stretching of the muscles. Low back extensor muscles are required to generate more active forces in weight holding or lifting after static flexion to compensate for the reduced contribution of creep deformed passive tissues in maintaining spinal stability and the posture. The degraded force generating capacity of the fatigued muscles can be a significant risk factor for low back pain.

Adaptação cultural de instrumento que avalia atividades do trabalho e sua relação com sintomas osteomusculares

OBJETIVO: Traduzir e adaptar culturalmente o questionário Work-related activities that may contribute to job-related pain and/or injury para o português falado no Brasil e verificar a validade de conteúdo desta nova versão. MÉTODOS: A adaptação cultural seguiu normas internacionalmente aceitas com as etapas de tradução, síntese, retro-tradução, avaliação por um comitê de especialistas e pré-teste. Esta versão do instrumento foi aplicada em 40 trabalhadores. RESULTADOS: O procedimento de adaptação cultural foi realizado com sucesso. O comitê de especialistas verificou a validade de conteúdo e realizou algumas modificações. No pré-teste, 7,5% dos indivíduos indicaram sugestões para um item do questionário e 17,5% demonstraram dificuldades no entendimento da instrução. Informações adicionais foram incluídas para tornar o instrumento final mais compreensível. CONCLUSÕES: A versão brasileira deste instrumento foi obtida com sucesso.

An in vivo assessment of the low back response to prolonged flexion: Interplay between active and passive tissues

BACKGROUND

Full flexion lumbar postures maintained over a prolonged period of time have been shown to lead to changes in the supporting passive structures of the spine and it has been hypothesized that this may lead to low back pain/disorders. However, the specific biomechanics and physiology of this link have not been fully developed. Of particular interest is the interplay between the active and passive extensor mechanisms and the role of rest break in this response.

METHODS

Ten healthy participants performed a regimen of a 10-min full lumbar flexion followed by a 10-min upright standing, with a slow speed isokinetic lift every 2.5min. Changes in the full lumbar flexion angle (system creep) and the electromyographic activity of back extensors in the isokinetic lifts were evaluated.

FINDINGS

Results showed significant increases in the full flexion angle and increased activity of the extensor muscles in the prolonged flexion to compensate for the reduced extension moment producing capability of the passive tissues. A 30-s rest break in the middle of the flexion moderated these viscoelastic responses.

INTERPRETATION

The results suggest that prolonged lumbar flexion results in the systematic transfer of an extension moment from passive tissues to active muscles. Heavy lifting or high force exertion of back muscles immediately after prolonged flexion could be a risk factor for low back disorders when the muscles lose their force generating capacity due to passive stretching. This study also indicated the importance of sufficient rest between consecutive full flexion tasks in reducing the risk.

Best practices for preventing musculoskeletal disorders in masonry: stakeholder perspectives

Brick masons and mason tenders report a high prevalence of work-related musculoskeletal disorders (WMSDs), many of which can be prevented with changes in materials, work equipment or work practices. To explore the use of "best practices" in the masonry industry, NIOSH organized a 2-day meeting of masonry stakeholders. Attendees included 30 industry representatives, 5 health and safety researchers, 4 health/safety specialists, 2 ergonomic consultants, and 2 representatives of state workers' compensation programs. Small groups discussed ergonomic interventions currently utilized in the masonry industry, including factors affecting intervention implementation and ways to promote diffusion of interventions. Meeting participants also identified various barriers to intervention implementation, including business considerations, quality concerns, design issues, supply problems, jobsite conditions and management practices that can slow or limit intervention diffusion. To be successful, future diffusion efforts must not only raise awareness of available solutions but also address these practical concerns.

Gonalgia entre trabalhadores e fatores ocupacionais associados: uma revisão sistemática

Com o objetivo de reunir informações sobre gonalgia entre trabalhadores e fatores ocupacionais associados, foi realizada uma revisão sistemática nas bases de dados MEDLINE, LILACS, SciELO, Free Medical Journals, entre outros, referentes ao período 1990-2006, usando-se os descritores gonalgia, knee, knee pain, knee joint, knee dislocation, knee injuries, work, workplace, workload, employment, occupations, industry, occupational, workers, arthrosis, osteoarthritis e seus equivalentes em português e espanhol. Dos 2.263 estudos inicialmente encontrados, somente 26 cumpriram os critérios necessários para permanecer na revisão. As prevalências de gonalgia nos últimos 12 meses variaram entre 11,2% e 60,9%, e os principais fatores associados foram: sexo feminino, idade avançada, índice de massa corporal elevado, trabalhar ajoelhado e carregar peso no trabalho.

Low back pain and musculoskeletal symptoms among Kansas farmers

BACKGROUND

Farming continues to rank as one of the most dangerous occupations in the United States. The purpose of this study was to determine the prevalence of low back pain and other musculoskeletal disorders (MSDs) among the farmers and to examine the factors associated with occupational back pain. Farmers in a predominately corn and soybean growing region of Kansas served as the study sample.

METHODS

Questionnaires were mailed out to 499 active farmers of a Farmers' Cooperative in Southeast Kansas. The self-administered questionnaire was used to determine the prevalence of self-reported symptoms of back pain and other MSDs and to determine the strength of associations between back pain and work factors.

RESULTS

The participation rate was 57.2%. The low back was the anatomical area with the highest prevalence of self-reported work-related pain (37.5%), followed by the shoulders (25.9%), knees (23.6%), and neck (22.4%). Close to 60% of the farmers reported that they experienced farm work-related MSD symptoms in at least one of the nine body areas in the previous year. Nearly one quarter of the farmers reported seeing a physician for their low back symptoms, and one in five farmers had to modify their work habits due to low back symptoms during the previous year.

CONCLUSIONS

Low back pain and other musculoskeletal conditions are a significant problem for Kansas farmers. This group of Kansas farmers experienced low back pain at a much higher rate than the general working population and higher than other groups of farmers previously studied.