Assessment of physical risk factors for the shoulder using the Posture, Activity, Tools, and Handling (PATH) method in small-scale commercial crab pot fishing

An observational work-sampling technique--Posture, Activity, Tools, and Handling (PATH)--was used to describe the prevalence of awkward postures and other physical risk factors for shoulder symptoms among a purposive sample of 11 small-scale commercial crab pot fishing crews. Fishing activities with awkward shoulder postures included hooking the buoy, feeding the rope into the hydraulic puller, and handling the crab pots. Increasing the size of the crew decreased the frequency of awkward shoulder postures for the captain but not for the mate. Awkward shoulder postures varied by technique, task distribution, equipment, and boat characteristics and setup, indicating these factors may be important determinants of exposure. Care should be taken in assuming personal techniques drives ergonomic exposure variability among these small-scale commercial fishermen.     

Laboratory evaluation of belt usage with apple buckets

BACKGROUND: Migrant and seasonal orchard harvest workers experience musculoskeletal strain caused by carrying heavy loads and holding awkward postures. An ergonomic hip belt designed to redistribute weight from the upper back, neck, and shoulders to the hips was evaluated. METHODS: A comparison of muscle exertion (using electromyography [EMG]) of four key back and shoulder muscles and shoulder surface pressure (using a surface pressure sensor [PS]) was made among 10 laboratory volunteers under intervention and control conditions, in two postures (standing erect [0 degrees ]) and flexed [45 degrees ]). RESULTS: All but one measure showed a significant reduction in the flexed posture with the intervention. Two of eight measures showed a significant reduction in the erect posture. Correlations with shoulder discomfort were found for deep shoulder EMG (r=0.71, P=0.021) and shoulder surface pressure (r=0.58, P=0.082). CONCLUSIONS: The hip belt intervention produces significant reductions in muscle activity while in a posture commonly assumed during orchard work.     

办公室职员与电脑操作相关动作的人类工效学评价

目的　探讨办公室职员与电脑操作相关不适症状的成因与预防措施。方法　采用问卷调查和电脑操作全息摄影人类工效学分析方法。结果　被访者在过去12个月患上与电脑操作相关的肌腱不适以颈部、肩膊、腰背部、大腿部发生率较高,分别为44 . 0 %、47 .0 %、5 9 .0 %、46 .0 %;职员电脑操作在使用鼠标时躯干平均向前倾斜13°,头位处于解剖位置18°、肩部高于解剖位置即耸肩姿态;并习惯将电脑屏幕置于右前方或左前方,导致电脑操作时呈侧身或扭腰不良姿势,与肌腱不适发生率高呈明显因果关系。结论　纠正不良工作姿势,消除过度紧张操作,设计符合工效学原则的作业场所、作业方式,有重要预防作用。     

Evaluation of questionnaire-based information on previous physical work loads. Stockholm MUSIC 1 Study Group. Musculoskeletal Intervention Center.

OBJECTIVES: The principal aim of the present study was to evaluate questionnaire-based information on past physical work loads (6-year recall). METHODS: Effects of memory difficulties on reproducibility were evaluated for 82 subjects by comparing previously reported results on current work loads (test-retest procedure) with the same items recalled 6 years later. Validity was assessed by comparing self-reports in 1995, regarding work loads in 1989, with worksite measurements performed in 1989. RESULTS: Six-year reproducibility, calculated as weighted kappa coefficients (k(w)), varied between 0.36 and 0.86, with the highest values for proportion of the workday spent sitting and for perceived general exertion and the lowest values for trunk and neck flexion. The six-year reproducibility results were similar to previously reported test-retest results for these items; this finding indicates that memory difficulties was a minor problem. The validity of the questionnaire responses, expressed as rank correlations (r(s)) between the questionnaire responses and workplace measurements, varied between -0.16 and 0.78. The highest values were obtained for the items sitting and repetitive work, and the lowest and "unacceptable" values were for head rotation and neck flexion. Misclassification of exposure did not appear to be differential with regard to musculoskeletal symptom status, as judged by the calculated risk estimates. CONCLUSIONS: The validity of some of these self-administered questionnaire items appears sufficient for a crude assessment of physical work loads in the past in epidemiologic studies of the general population with predominantly low levels of exposure.     

Effects of a Proximity-Sensing Feedback Chair on Head, Shoulder, and Trunk Postures When Working at a Visual Display Terminal

Introduction: This study was designed to identify the effects of feedback from a proximity-sensing chair on head, shoulder, and trunk postures when working at a visual display terminal (VDT). Methods: Twenty healthy adults were asked to perform VDT work, and their forward head, forward shoulder, and trunk flexion angles were analyzed using a 3-D motion analysis system. The statistical significance of differences between without and with an auditory feedback device was tested by paired t-tests, with the significance cutoff set at α=0.05. Results: The forward head, forward shoulder, and trunk flexion angles significantly decreased during VDT work when using the proximity sensor with auditory feedback. Conclusion: We suggest that a feedback device promotes the adoption of beneficial postures, which may be effective in preventing VDT-work-related neck and upper-limb disorders.     

Work-related psychosocial and mechanical risk factors for neck/shoulder pain: a 3-year follow-up study of the general working population in Norway

Purpose

This study examines the impact of work-related psychosocial and mechanical exposure on the development of neck/shoulder pain in the general working population.

Methods

A randomly drawn cohort from the general population in Norway aged 18–66 was followed up for 3 years (n = 12,550, response rate = 67 %). Eligible respondents were in paid work during the reference week in 2006 and 2009, or temporarily absent from such work (n = 6,745). Four work-related psychosocial factors and six mechanical exposures were measured. Outcomes of interest were moderate or severe neck/shoulder pain at follow-up adjusted for baseline neck/shoulder pain.

Results

In total, 16.9 % (1,138 individuals) reported neck/shoulder pain during the last month at follow-up. Work related psychosocial predictors of neck/shoulder pain were high job demands (highest OR 1.41, 95 % CI 1.11–1.78) and low levels of supportive leadership (highest OR 1.66, 95 % CI 1.08–2.54). Mechanical factors were neck flexion (highest OR 1.77, 95 % CI 1.31–2.39) and lifting in awkward postures (highest OR 1.81, 95 % CI 1.21–2.71). The estimated population risk attributable to these factors was about 23 %. The relative risk for neck/shoulder pain associated with psychosocial exposure was slightly influenced by adjustment for physical risk factors, and vice versa. There was no substantial confounding related to age, gender, education, occupation or psychological distress.

Conclusions

Highly demanding jobs, neck flexion and awkward lifting appear as the most important predictors of neck/shoulder pain.     

Trunk Posture Exposure Patterns among Prairie Ranch and Grain Farmers

ABSTRACT

Objectives: Low back disorders (LBD) are the most common musculoskeletal disorder among farmers, and awkward trunk postures such as repetitive bending are often cited as a contributor. However, it is not clear whether trends of increasing mechanization in agriculture may be impacting the requirement for trunk-intensive tasks. This study compared the patterns of working trunk posture among prairie farmers during both machine-intensive and non-intensive work days.

Methods: Forty-nine adult farm workers from 22 farms participated in this study. Individual and farm characteristics were documented via questionnaire. Trunk angles and velocities were measured with an I2M inertial sensor placed on the chest. Participants completed electronic posture assessments during up to three regular work days throughout the growing season for a total of 91 electronic posture measurements. Forward and lateral trunk bending patterns were expressed in three domains: magnitude, duration, and frequency.

Results: Working tasks were categorized into driving, manual, and mixed. Driving was the most commonly measured task (52% of work days), and mixed tasks the least (12%). Both 90th percentile trunk flexion-extension angles and velocities were significantly higher for manual as compared to driving tasks. Participants spent 38% of their working time in trunk forward flexion ≥ 20°, which, according to previous epidemiological studies, may increase their risk for LBD.

Conclusion: The directly-measured trunk posture exposure patterns in this study suggest that machinery-intensive workdays result in less awkward trunk posture and lower velocities. Increasing mechanization invites more research on the exposures associated with machinery operation and increasing automation.     

Postures and movements in the most common tasks of power line workers

The repair and maintenance of electrical power lines involves awkward postures, which are known risk factors for developing musculoskeletal disorders. The aim of the present study was to quantify postures and movements of upper arm, head, upper back and neck in the main tasks performed by line workers. Posture of twelve right-handed line workers was recorded by inclinometry and presented as percentiles of angular and angular velocity distributions. All tasks involved considerable upper-arm elevation, ranging from 73° to 115° for the 90th percentile. Upper-arm elevation showed significant differences between tasks, but no consistent differences between right and left sides. Regarding velocity, the right arm presented higher levels than the left arm. All tasks required significant extension of head, upper back and neck, ranging from 7° to 67° for head (10th percentile). All tasks, except the one performed with a continuous extension, also involved pronounced flexion, ranging from 33° to 60° for the head (90th percentile). Work which required highly elevated arms also required significant head extension (r(2)=0.56). Awkward postures of upper arms, head, upper back and neck were identified by inclinometry, demonstrating the need for preventative interventions to reduce musculoskeletal disorders among line workers.     

Prevalence of upper extremity symptoms and possible risk factors in workers handling paper currency

The prevalence of upper extremity symptoms in the workforceis high, particularly in industries characterized by forceful,repetitive or awkward movements. A study was undertaken to assessthe prevalence of upper extremity symptoms in bank workers ina paper currency processing operation and to examine the roleof possible risk factors for these complaints. Thirty-nine workersof a total workforce of 47 were assessed with a questionnaireand physical examination. The questionnaire collected informationabout demographics, health status, symptom reporting, psychosocialwork stressors and other work exposure characteristics. Overall,59% of the workers reported having significant work-relatedupper extremity musculoskeletal symptoms in the preceding year,including 49% with neck and shoulder symptoms and 49% with armand wrist symptoms. In this study the key predictive factorfor upper extremity musculoskeletal symptoms was psychologicaljob demands. The workers had similar ergonomic stressors (withlittle gradient of exposure) and therefore our results do notcontradict the importance of ergonomic factors in the developmentof upper extremity symptoms. However, the results do suggestthat within a group exposed to similar ergonomic stressors,psychological job demands may be an important factor associatedwith musculoskeletal symptoms.     

Health hazards of photography

Photographers are exposed to chemical, physical, and psychological hazards during the course of their work. Photojournalists are at physical risk from motor vehicle crashes and work in war zones. Ergonomic risk comes from handling heavy equipment as well as work in awkward postures in dangerous positions. Darkroom exposure to chemical agents may lead to respiratory, allergic, and nervous system disease. Psychological problems come from chaotic work organization. Digital photography may reduce the prevalence of chemical exposure, although it may increase the risk of musculoskeletal illness. Simple hygiene measures may prevent illness in photographers. An increasing number of printed resources is available to professional and amateur photographers; this information may help them protect their health while they enjoy their art.     

Video display terminal workstation improvement program: II. Ergonomic intervention and reduction of musculoskeletal discomfort

The effects of an ergonomic intervention on musculoskeletal discomfort in 118 video display terminal (VDT) users were assessed 1 year after intervention. The intervention consisted of recommended changes to workstations, which were based on the evaluation of 15 ergonomic characteristics. Compliance with the intervention was at least 75% for most workstation characteristics. Reduction in discomfort was substantial and was highest for the wrist/hand (57%), lower back (43%), and neck/shoulder (41%) severity of discomfort outcomes. Neither compliance with intervention on individual workstation characteristics nor summary intervention scores were associated with reduction in discomfort. Our results demonstrate that although reduction of musculoskeletal discomfort may be observed in the context of an intervention study, it may be difficult to link these benefits to specific interventions.     

Prevalence of musculoskeletal disorders among Indian railway sahayaks

Railway sahayak or also known as coolie is one of the oldest occupations in India. This occupational group is continuously subjected to various musculoskeletal problems due to repetitive load exertion in unnatural postures. The present research aims to examine the prevalence of musculoskeletal disorders (MSDs) among Indian railway sahayaks. A cross-sectional study has been conducted on a sample of 51 male sahayaks. With a modified Nordic questionnaire, data were collected on their demographics, work, and musculoskeletal pain history. Electromyography (EMG) of the upper trapezius muscle of selected 12 healthy sahayaks having no history of neck–shoulder complaints were analyzed under different load lifting and carrying conditions. Additionally, ergonomic risk levels were recorded using Rapid Entire Body Assessment method. The questionnaire revealed that for the past 1 year prevalence, the most affected body regions of railway sahayaks were neck (47%), shoulder (51%), lower back (43%), and knee (47%). The association between age group and MSDs in different body regions were found significant (p = 0.012 for neck, p = 0.017 for shoulder, etc.). Work experience also had a significant relation to the MSDs in different body regions (p = 0.013 for shoulder,p = 0.023 for calf, etc.). Analysis of variance reveals high significance level between EMG values and tasks performed by the sahayaks. In conclusion, railway sahayaks were found to have high rate of MSDs which may be associated with lifting/carrying heavy loads in awkward postures. Ergonomic interventions must be implemented to reduce the risk level on this group of workers.     

Quantitative measurement of stressful trunk postures in nursing professions

INTRODUCTION: The evaluation of stress to the spinal column in the provision of care has mostly concentrated on the handling of loads. However, awkward body postures alone, without load transfer, can also be stressful for the spinal column. Therefore in this study all the body postures and movements of nurses were quantitatively measured within a working shift. METHODS: The body postures were recorded with the CUELA measurement system (computer-assisted recording and long-term analysis of musculoskeletal loads), coupled to the individual, and this detected all movements of the trunk and the legs. These measurements were supported by video recordings, so that exact allocation of the measured data to the tasks performed was possible. In all, 24 shift measurements were carried out in 8 wards. Extent, frequency and duration of trunk postures were measured in three planes and assessed on the basis of several standards (DIN EN 1005-1, DIN EN 1005-4, ISO 11226). RESULTS: A mean of 1131 (+/-377) trunk inclinations of >20 degrees were performed in each shift. This corresponds to a frequency of 3.5 min(-1). A total of 237 of these inclinations lasted for >4 s. A total of 72 (+/-35) min was spent bending forward with an inclination of >20 degrees . However, the mean time spent in transferring patients (counting only the lifting process) and heavy materials was only 2 min per shift. Postures with trunk inclination of >60 degrees were adopted for a mean of 175 (+/-133) times. The main tasks responsible for this were 'bed making' (21%), 'basic care' (16%) and 'clearing up/cleaning' (16%). CONCLUSIONS: It could be shown that many stressful trunk postures are assumed in nursing work during a shift. Future preventive measures should therefore consider not only load handling but also tasks with awkward postures.     

Physiological and subjective assessment of food grain handling workers in West Godavari district, India

There are many rice mills and food grain depots where a large number of workers are engaged for processing paddy and rice, storage and distribution. Lifting, carrying and depositing sacs of food grain are the major jobs carried out by these workers. The present study was undertaken to evaluate the workers with respect to their nutritional status, workload, energy expenditure and musculoskeletal pain or discomfort resulting out of work practice. Average peak heart rate of the depot and rice mill workers suggested the workload as moderate to very heavy. Their average energy expenditure values also indicated the workload as moderate to heavy. Subjective assessment of the workers showed the workload as heavy for 60.7% depot workers and 23.1% rice mill workers. Musculoskeletal pain or discomfort was maximally reported in knee by 59% depot workers whereas low back and knee was reported by 61.5% rice mill workers. Besides the weight of the sac, awkward postures like bending and twisting of trunk adopted frequently causes the problem. Further studies and rationalization of work method may improve the health and safety of the workers.     

Investigation of Select Ergonomic Interventions for Farm Youth. Part 2: Wheelbarrows

ABSTRACT

Previous research has provided evidence that farm youth performing farm chores may be at risk of developing a low back musculoskeletal injury. In order to reduce these risks, effective interventions for reducing the stressors that cause the injuries are needed. The objective of the current study was to investigate alternative wheelbarrow styles as an intervention for youth working to transfer material on the farm with respect to trunk motion and perceived exertion. A lumbar motion monitor was used to capture three-dimensional trunk kinematics while several wheelbarrow tasks (e.g., pushing, pushing over bump, and dumping) were performed by youth. Ratings of perceived exertion and comfort of use were also assessed. Results indicated a reduction in the sagittal trunk flexion and velocity was achieved by adding a push bar to the handles, in combination with three-wheels, or utilizing adjustable handles. However, these alterations had little impact in the predicted low back disorder risk levels. Additionally, the youths' perceptions of risk and exertion levels were greater for these alternative wheelbarrows than for the regular wheelbarrow. Therefore, the mismatch between perception and kinematic response will probably affect usage of the alternative wheelbarrows. While the results indicate that alternative wheelbarrow designs can reduce the awkward postures and motions during wheelbarrow tasks, further research into the effectiveness of these interventions, including spine loading and long long-term use, is necessary.     

Repeatability and validity of an upper limb and neck discomfort questionnaire: the utility of the standardized Nordic questionnaire

The repeatability and validity of a questionnaire for upper limb and neck complaints were assessed in a population of 105 hospital outpatients with a range of upper limb and neck disorders (including cervical spondylosis, adhesive capsulitis, lateral epicondylitis, carpal tunnel syndrome and Raynaud's phenomenon). Subjects were asked to complete a modified Nordic-style upper limb and neck discomfort questionnaire on two occasions closely spaced in time. The repeatability of their responses was assessed by calculating a kappa coefficient (kappa), and the sensitivity and specificity of component items in the questionnaire were determined for specific diagnostic categories of upper limb and neck disorder. Symptom reports for pain in the upper limb and neck, pain interfering with physical activities, neurological symptoms and blanching were all found to be highly repeatable (kappa = 0.63-0.90). A number of regional pain reports proved to be very sensitive in relation to specific upper limb disorders, but, with the exception of reported finger blanching in patients with Raynaud's phenomenon, none proved to have a good specificity (range = 0.33-0.38). We conclude that a modified Nordic-style questionnaire is repeatable and sensitive, and is likely to have a high utility in screening and surveillance. However a complementary examination schedule of adequate specificity and repeatability is essential to establish a clinical diagnosis.     

Perceived physical demands and reported musculoskeletal problems in registered nurses

BACKGROUND: Nursing is physically demanding, and nurses have higher rates of musculoskeletal disorders (MSDs) than most other occupational groups. The physical demands of nursing may lead some nurses to leave the profession, contributing to the shortage of registered nurses in many workplaces that is a major concern today. As a first step toward reducing MSDs and their consequences, this study was designed to examine the relationship between perceived physical demands and reported neck, shoulder, and back MSDs in nurses. METHODS: Data were collected anonymously from 1163 randomly selected working nurses (74% response rate) using a cross-sectional survey. The 12-item survey scale (internal reliability coefficient=0.89), rated perceived physical demands such as force, awkward postures, and heavy lifting. Nurses with a presumed MSD case reported relevant past-year symptoms in the neck, shoulder, and/or back lasting >or=1 weeks, or at least monthly, with moderate or more pain, on average. RESULTS: Moderate and high perceived physical demands were significantly associated with reported neck, shoulder, and back MSD cases, even after adjustments for demographic and lifestyle-related covariates. Adjusted odds ratios for highly demanding work (vs low) ranged from 4.98 to 6.13 depending on body site. When analyses were restricted to staff nurses only, the odds ranged from 9.05 to 11.99. CONCLUSIONS: Perceived physical demands are associated with reported MSD in registered nurses, and the association is stronger in staff nurses.     

汽车装配作业工人肌肉骨骼损伤的流行病学调查研究

目的 调查汽车装配作业工人肌肉骨骼疾患的发生情况,探讨可能的相关影响因素.方法 选择北方某汽车制造公司1508名装配作业工人作为调查对象,采用区域工种检查表、北欧标准化肌肉骨骼症状调查表(NMQ)与疼痛问卷,对调查对象的一般情况、不良工效学因素接触情况和肌肉骨骼疾患发生情况等进行流行病学横断面和回顾性调查.结果 汽车装配作业工人肌肉骨骼疾患发生部位以下背部为最高,其次为手腕部、颈部和肩部,发生较为严重的工段有发动机舱段、内饰段、门盖段、底盘段和调试段.发动机舱段和底盘段作业工人以下背部,内饰段以下背部和手腕部,门盖段以手腕部,调试段以颈部和下背部为肌肉骨骼损伤的主要部位.颈部肌肉骨骼疾患有随身高的增高而加重的趋势;吸烟可能会增加肌肉骨骼疾患的发生.结论 汽车装配作业工人肌肉骨骼疾患发病较为严重,各工段发生部位各有不同,表现特征比较明显,可能与其存在的不良作业姿势或活动有关.作业工人身高和吸烟习惯可能是影响肌肉骨骼疾患发生的重要因素.     

Computer use and habitual spinal posture in Australian adolescents

OBJECTIVE: Computer use is common in adolescents, and there is evidence that adolescent spinal posture alters during computer use. However, it is unknown if computer use and habitual postures are associated. The objective of this study was to evaluate associations between adolescent computer use and habitual postures. METHODS: Eight hundred eighty-four adolescents (408 females, 476 males, mean age, 14.0 years, standard deviation, 0.2) completed a questionnaire assessing weekly computer use. Habitual spinal posture was assessed by photographic analysis while standing and sitting. RESULTS: Computer use was associated with adolescent habitual postures. In males, increased computer use was associated with increased head flexion and neck flexion. In females, increased computer use was associated with increased lumbar lordosis. CONCLUSIONS: The amount of weekly computer use was associated with changes in habitual spinal postures, and these depended on gender. These associations may result from temporary computer postures leading to adaptive neuromusculoskeletal changes, though further multivariate and longitudinal studies are needed to confirm causality. As some habitual posture changes may place a greater strain on the musculoskeletal system, computer use by adolescents should be viewed as a possible health concern.