Internal consistency,test–retest reliability and concurrent validity of a questionnaire on work-related exposure related to arm,shoulder and neck symptoms in computer workers

The aim of this study was to determine the internal consistency, test–retest reliability and concurrent validity of the RSI QuickScan, a newly developed questionnaire that aims to identify the presumed risk factors for neck, shoulder and arm symptoms in a population of computer workers. The internal consistency was calculated using item analysis. The test–retest reliability and concurrent validity were analysed by calculating the percentage of agreement, Cohen's Kappa and the Ppositive and Pnegative. The concurrent validity was also tested by comparing the results from the new questionnaire with those from the original questionnaires that the current questionnaire was based on, on-site expert observations and direct measurements. The results indicate that the RSI QuickScan is a measurement tool with acceptable internal consistency, reliability and concurrent validity. The questionnaire can be used as a means to rapidly collect data on a large population of office workers and at low cost.     

A field comparison of neck and shoulder postures in symptomatic and asymptomatic office workers

Poor neck and shoulder postures have been suggested to be a cause of neck and shoulder pain in computer workers. The present study aimed to evaluate and compare the head, neck and shoulder postures of office workers with and without symptoms in these regions, in their actual work environments. The two all female subject groups reported significantly different discomfort scores across five trials repeated in a single working day. The results of repeated video capture and two-dimensional motion analysis showed that there were trends for increased head tilt and neck flexion postures in the symptomatic subjects (n = 8), compared to the asymptomatic subjects (n = 8). Symptomatic subjects also tended to have more protracted acromions compared with asymptomatic subjects and showed greater movement excursions in the head segment and the acromion. All subjects demonstrated an approximately 10% increase in forward head posture from their relaxed sitting postures when working with the computer display, but there were no significant changes in posture as a result of time-at-work.     

Assessing exposure to risk factors for work-related musculoskeletal disorders using Quick Exposure Check (QEC) in taxi drivers

Work-related musculoskeletal disorders (WMSDs) are a common health problem throughout the world. This study aimed to examine the risk factors that are involved in the development of WMSDs in taxi drivers. In total 382 taxi drivers were observed using Quick Exposure Check (QEC) observational tool, which allows practitioners and workers to assess four key areas of the body. Results of the QEC scores were found to be very high for the shoulder/arm, wrist/hand and neck, whereas the scores for the back were found to be high for static use and moderate for moving. The results also showed that the occupational risk factors for WMSDs were associated with restricted postures, repetitive movements, vibration, work related stress. Essential ergonomic interventions are needed to eliminate risk of exposures to WMSDs in taxi drivers.Relevance to industryThe study results have relevance for ergonomists, health and safety practitioners as well as the drivers themselves, and helpful for estimating the main physical risk factors for WMDSs before choosing a method prior to an ergonomic intervention in industry.     

The biomechanical demands of manual scaling on the shoulders & neck of dental hygienists

Abstract

The purpose of this study was to evaluate the postural and muscular demands placed on the shoulders and neck of dental hygienists when performing a simulated manual scaling task. Nineteen healthy female dental hygienists performed 30-min of simulated manual scaling on a manikin head in a laboratory setting. Surface electromyography was used to monitor muscle activity from several neck and shoulder muscles, and neck and arm elevation kinematics were evaluated using motion capture. The simulated scaling task resulted in a large range of neck and arm elevation angles and excessive low-level muscular demands in the neck extensor and scapular stabilising muscles. The physical demands varied depending on the working position of the hygienists relative to the manikin head. These findings are valuable in guiding future ergonomics interventions aimed at reducing the physical exposures of dental hygiene work.

Practitioner Summary: Given that this study evaluates the physical demands of manual scaling, a procedure that is fundamental to dental hygiene work, the findings are valuable to identify ergonomics interventions to reduce the prevalence of work-related injuries, disability and the potential for early retirement among this occupational group.     

Towards exposure limits for working postures and musculoskeletal symptoms – a prospective cohort study

Occupational postures are considered to be an important group of risk factors for musculoskeletal pain. However, the exposure-outcome association is not clear yet. Therefore, we aimed to determine the exposure-outcome association of working postures and musculoskeletal symptoms. Also, we aimed to establish exposure limits for working postures. In a prospective cohort study among 789 workers, intensity, frequency and duration of postures were assessed at baseline using observations. Musculoskeletal pain was assessed cross-sectionally and longitudinally and associations of postures and pain were addressed using logistic regression analyses. Cut-off points were estimated based on ROC-curve analyses. Associations were found for kneeling/crouching and low-back pain, neck flexion and rotation and neck pain, trunk flexion and low-back pain, and arm elevation and neck and shoulder pain. The results provide insight into exposure-outcome relations between working postures and musculoskeletal symptoms as well as evidence-based working posture exposure limits that can be used in future guidelines and risk assessment tools.

Practitioner Summary: Our study gives insight into exposure-outcome associations of working postures and musculoskeletal symptoms (kneeling/crouching and low-back pain, neck flexion/rotation and neck pain, trunk flexion and low-back pain, and arm elevation and neck and shoulder pain). Results furthermore deliver evidence-based postural exposure limits that can be used in guidelines and risk assessments.     

Shoulder and neck muscle activities during typing with articulating forearm support at different heights

Use of forearm support is known to reduce physical stress of computer users, but research about how to properly position the forearm support is insufficient. This study was aimed to determine whether the height of forearm support influences muscular loads during typing. Twenty four subjects performed a typing task with a pair of articulating forearm support at three different heights as well as without any support, while shoulder, neck and forearm muscle activities and posture data were recorded. Typing with the support at resting elbow height produced significantly (p < 0.05) lower shoulder and neck muscle activities than that of no support condition. Typing with the support at heights higher than the resting elbow height produced significantly greater shoulder and neck muscle activities compared to the no support condition. Results suggest that forearm support can help computer users lessen physical stress in typing, but only when the supports are positioned at resting elbow height.

Practitioner Summary: Use of forearm support is known to alleviate physical stress of PC users in computer works such as typing. This experimental study addressed the importance of proper positioning of forearm support by comparing neck and upper extremity muscle activities between conditions with varying heights of forearm support in keyboard typing.     

Overhead work and shoulder-neck pain in orchard farmers harvesting pears and apples

The effects of overhead work were studied by comparing orchard farmers’ musculoskeletal symptoms while bagging pears with those same symptoms while bagging apples. The subjects were 52 Japanese female fanners, who were examined twice an evening in late June for bagging pears, and during another evening of late July for bagging apples, when each task had been almost finished. They were questioned about musculoskeletal complaints of stiffness and pain during each job, and examined for muscle tenderness and pain from joint movement. Arm elevation angles during the work were measured for each type of bagging. The prevalence of stiffness and pain in the neck and shoulder, muscle tenderness in the shoulder regions, and pain in neck motion were found to be significantly higher when bagging pears than apples. Musculoskeletal symptoms of parts other than the neck and shoulder did not differ between the two types of bagging. The working posture of elevating the arm more than 90° was assumed to account for 75% of the time bagging pears, against 40% for bagging apples. Overhead work requiring arm elevation and head extension was considered to be closely related with shoulder-neck disorders among farmers.     

DASH questionnaire for the analysis of musculoskeletal symptoms in industry workers: a validity and reliability study

Purpose

The disabilities of the arm, shoulder and hand (DASH) questionnaire is a self-administered region-specific outcome instrument developed as a measure of self-rated upper-extremity disability and symptoms. The aim of this study was to evaluate the reliability and the construct validity of the DASH questionnaire by establishing its correlation to the Medical Outcomes Study Short Form-36 (SF-36) in industry workers. Also we aimed to investigate whether the DASH can be used as a standardized questionnaire to evaluate the work-related musculoskeletal disorders (WMSDs) in upper extremity in industrial settings and epidemiological studies.

Material and methods

The Turkish version's reliability and construct validity were evaluated in 240 industry workers with upper-extremity musculoskeletal complaints. Workers were asked to complete a packet that included the DASH and the SF-36. Test-retest reliability was assessed in all workers who filled in the DASH questionnaire 15 days later. Construct validity was evaluated by comparing the overall and work component DASH scores with SF-36 summary and subscales.

Results

The mean DASH score for the textile workers whose duties were confection, dyeing, sewing, quality control and packaging was calculated as 65, 55, 68, 54 and 67, respectively. As a result of this study, pain intensity in shoulder, wrist and hand was significantly associated with the DASH score (p<0.05). Internal consistency of the DASH was high (Cronbach alpha 0.91). Test-retest reliability was excellent for the overall DASH (intraclass correlation coefficient (ICC) 0.92). Moderate correlations (p<0.05) were found between the overall and work component DASH and the SF-36 summary scales. Pearson correlation coefficients of the overall and work component DASH to the SF-36 subscales ranged from −0.33 to −0.82.

Conclusion

These results support that DASH is a reliable and valid instrument to measure functional disability and investigate the ergonomic risk factors in textile workers with upper-extremity musculoskeletal complaints.     

A prospective cohort study of neck and shoulder pain in professional drivers

In a three-year follow-up study, the occurrence of neck and shoulder pain (NSP) in terms of frequency, duration and intensity was investigated in a population of 537 male professional drivers. Over the follow-up period, the cumulative incidences for neck and shoulder pain were 31.9% and 21.4%, respectively. After adjustment for potential confounders, a measure of cumulative whole-body vibration exposure was significantly associated with all NSP outcomes. Lifting loads and work with hands above shoulder level were significantly related to shoulder outcomes, while driving with trunk bent or twisted was associated with neck pain. Limited job decision, low social support and job dissatisfaction were significant predictors of neck outcomes. Psychological distress was associated with all NSP outcomes. The findings of this cohort study suggest that NSP outcomes are of multifactorial origin in driving occupations.

Practitioner Summary: This prospective cohort study highlighted the multifactorial nature of neck and shoulder pain (NSP) outcomes in a population of professional drivers. Cumulative whole-body vibration exposure, physical load factors and adverse psychosocial environment at the workplace, as well as individual-related psychological distress, were significant predictors of the occurrence of NSP in the professional drivers.     

Disorders of the cervicobrachial region among female workers in the electronics industry

Ninety-six female employees in the electronics industry were investigated in a cross-sectional study. Symptoms from the neck, shoulder-neck angle, shoulder, arm and thoracic spine regions were coded according to four degrees of severity, and related to individual characteristics. Static muscle strength of five shoulder and arm muscle groups, as well as static endurance were not related to symptoms; nor were medical and work history, productivity, leisure physical activity or hobbies. For the evaluation of postures and movements of the neck, shoulder and upper arm during work a systematic video technique (VIRA) was developed. Large interindividual differences in working technique, and thereby in work load, were obtained. Some of these measures, especially those describing flexion and abduction of the upper arm, were related to symptoms in the neck and shoulder. Stepwise multiple regression analyses confirmed and strengthened these relationships.     

Reproducibility of a self-report questionnaire for upper extremity musculoskeletal disorder risk factors.

A self-report questionnaire was developed to evaluate the potential for assessment of possible risk factors for musculoskeletal disorders. Visual-analog and categorical scales were designed to represent responses relating to primary work as well as a second job and hobbies or non-work activities. 71 tree nursery workers completed the scales twice in consecutive weeks. Agreement between means of the two questionnaire administrations was 0.80 or higher for all scales. Intraclass correlation coefficients ranged between 0.59 and 0.69 for the primary job hand/wrist responses and between 0.49 and 0.82 for non-work/hobby neck and upper arm scales. These results show potential for future application of similar scales in industry or temporary and seasonal work to evaluate exposure to upper extremity risk factors.     

The investigation of work-related musculoskeletal disorders among female workers in a hazelnut factory: Prevalence,working posture,work-related and psychosocial factors

BackgroundWork-related musculoskeletal disorders (WMSDs) are the most common occupational health problems in the industrialized world. The identification of WMSDs specific to occupation is essential to plan and implement preventative programs. This study investigated the prevalence of WMSDs and determined the factors related to the severity of the most common disorders among female workers in a hazelnut factory.MethodsA total of 114 female workers were examined in this cross-sectional study using the Nordic Musculoskeletal Questionnaire, the Dutch Musculoskeletal Questionnaire, and an author-developed questionnaire (for socio-demographic characteristics and psychosocial factors). Working posture, craniovertebral angle, thoracic kyphosis angle (TKA), and lumbar lordosis angle were evaluated based on a photogrammetry method using the ImageJ program.ResultsThe prevalence of WMSDs in at least one body part during the last 12 months was 92.1%. The highest prevalence of WMSDs was in the lower back (61.4%), neck (57.9%), shoulder (53.6%), and upper back (45.6%). The least affected part was the elbow. Lower back, shoulder, and neck disorders were the most common causes of activity limitation. The severity of lower back pain was associated with stress in the workplace and work-related factors. The neck pain severity was related to craniovertebral angle and work-related factors. The shoulder pain severity increased with TKA and employment duration. TKA was related to upper back pain severity.ConclusionsWMSDs are common among female workers in a hazelnut factory. Reorganizing of working posture, work-related factors, and stress at work may be beneficial to decrease the prevalence of WMSDs and pain severity.Relevance to Industry; The female workers in the hazelnut factory are vulnerable to the work-related musculoskeletal disorders, particularly in the spinal region. The employers should endeavor to improve the health of the workers by the adjustment of the working posture and environmental factors.     

Biomechanics and performance when using a standard and a vertical computer mouse

Objective: to compare the biomechanics and performance while using a vertical computer mouse (VM) and a standard mouse (SM). Methods: muscle activation (electromyography), forearm movements (electrogoniometers), performance (Fitts' Law test) and satisfaction (questionnaire) of 16 subjects were evaluated. Results: there were significant differences between the VM and the SM, respectively, on motion (28° vs. 42° pronation, p = 0.001; 5° ulnar vs. 7° radial deviation, p = 0.016) and muscle activity (13% vs. 16% of extensor carpi activity, p = 0.006; 10% vs. 13% extensor digitorum activity, p = 0.001). VM user satisfaction was good (68); however, time to target was longer (4.2 vs. 3.4 s, p < 0.001). Conclusions: using the VM decreased wrist pronation and lowered wrist extensor muscle activity, but additional training and familiarisation time may be required to improve user performance.

Practitioner Summary: Using a vertical mouse can decrease the exposure to biomechanical risk factors for computer mouse use-related musculoskeletal disorders. Using a vertical computer mouse resulted in less wrist pronation and lower wrist extensor muscle activity. But, training and familiarisation are required.     

Associations of ergonomic and psychosocial work hazards with musculoskeletal disorders of specific body parts: A study of general employees in Taiwan

Background and aimsMusculoskeletal disorders (MSDs) are major occupational health concerns. This study examined the associations of ergonomic and psychosocial work hazards with the risks of MSDs of specific body parts and their distribution across a wide range of occupational groups.MethodsStudy participants comprised 8,937 male and 7,052 female employees aged 20–65 years from a nationwide survey in 2016. A self-report questionnaire was administered to obtain information regarding demographic characteristics, work conditions, ergonomic and psychosocial work hazards, and MSDs of different body parts in 12 months. Multivariate logistic regression models were used to estimate prevalence ratios of MSDs in relation to ergonomic and psychosocial work hazards.ResultsIn professionals and skilled workers, MSDs of the neck and shoulders were more prevalent, whereas in manual workers, MSDs of the hands, wrists, and lower back were more prevalent. Psychosocial work hazards, including high psychological demand and low workplace justice, were major work-related risk factors for shoulder and neck disorders, whereas ergonomic hazards were major work-related risk factors for lower back and wrist or hand disorders.ConclusionDifferent workplace hazards contribute to the risks of different MSDs. To prevent the development of MSDs, occupational health professionals should evaluate both ergonomic and psychosocial work hazards and develop health prevention programs tailored to the risk profiles of working populations.     

Neck/shoulder pain,habitual spinal posture and computer use in adolescents: the importance of gender

Neck/shoulder pain is a common complaint, with evidence suggesting rates in adolescence have increased in line with increased computer use. The study aimed to examine the influence of gender on relationships between computer use, habitual posture and neck/shoulder pain. Adolescents (n = 1483) participating in the 14 year follow-up of the Raine Study cohort were surveyed for computer use, habitual sitting posture and neck/shoulder pain. Females used computers less than males (52% vs. 45% used for up to 7 h per week). Females sat much more upright than males with greater anterior pelvic tilt (9.4° vs. 0.4°). Females reported a higher 1 month prevalence of neck/shoulder pain (34.7%) than males (23.1%). A multivariate model showed neck/shoulder pain risk was increased in females (OR 2.61, 95% CI 1.70–4.00) and with computer use (OR 1.19, CI 1.01–1.40). Computer use is related to neck/shoulder pain and posture in adolescents but this relationship is different in boys and girls.

Statement of Relevance: This study showed the confounding effect of gender on the relationships among computer use, posture and neck/shoulder pain and thus the need to consider genders separately in research and practice aiming to optimise young people's use of computers.     

Vibrations transmitted from human hands to upper arm,shoulder, back,neck, and head

Some powered hand tools can generate significant vibration at frequencies below 25 Hz. It is not clear whether such vibration can be effectively transmitted to the upper arm, shoulder, neck, and head and cause adverse effects in these substructures. The objective of this study is to investigate the vibration transmission from the human hands to these substructures. Eight human subjects participated in the experiment, which was conducted on a 1-D vibration test system. Unlike many vibration transmission studies, both the right and left hand-arm systems were simultaneously exposed to the vibration to simulate a working posture in the experiment. A laser vibrometer and three accelerometers were used to measure the vibration transmitted to the substructures. The apparent mass at the palm of each hand was also measured to help in understanding the transmitted vibration and biodynamic response. This study found that the upper arm resonance frequency was 7–12 Hz, the shoulder resonance was 7–9 Hz, and the back and neck resonances were 6–7 Hz. The responses were affected by the hand-arm posture, applied hand force, and vibration magnitude. The transmissibility measured on the upper arm had a trend similar to that of the apparent mass measured at the palm in their major resonant frequency ranges. The implications of the results are discussed.Relevance to industryMusculoskeletal disorders (MSDs) of the shoulder and neck are important issues among many workers. Many of these workers use heavy-duty powered hand tools. The combined mechanical loads and vibration exposures are among the major factors contributing to the development of MSDs. The vibration characteristics of the body segments examined in this study can be used to help understand MSDs and to help develop more effective intervention methods.     

This month ‘Technik ist alles’

The objective of this prospective cohort study was to evaluate if peak or cumulative musculoskeletal discomfort may predict future low-back, neck or shoulder pain among symptom-free workers. At baseline, discomfort per body region was rated on a 10-point scale six times during a working day. Questionnaires on pain were sent out three times during follow-up. Peak discomfort was defined as a discomfort level of 2 at least once during a day; cumulative discomfort was defined as the sum of discomfort during the day. Reference workers reported a rating of zero at each measurement. Peak discomfort was a predictor of low-back pain (relative risk (RR) 1.79), neck pain (RR 2.56), right or left shoulder pain (RR 1.91 and 1.90). Cumulative discomfort predicted neck pain (RR 2.35), right or left shoulder pain (RR 2.45 and 1.64). These results suggest that both peak and cumulative discomfort could predict future musculoskeletal pain.     

Does musculoskeletal discomfort at work predict future musculoskeletal pain?

The objective of this prospective cohort study was to evaluate if peak or cumulative musculoskeletal discomfort may predict future low-back, neck or shoulder pain among symptom-free workers. At baseline, discomfort per body region was rated on a 10-point scale six times during a working day. Questionnaires on pain were sent out three times during follow-up. Peak discomfort was defined as a discomfort level of 2 at least once during a day; cumulative discomfort was defined as the sum of discomfort during the day. Reference workers reported a rating of zero at each measurement. Peak discomfort was a predictor of low-back pain (relative risk (RR) 1.79), neck pain (RR 2.56), right or left shoulder pain (RR 1.91 and 1.90). Cumulative discomfort predicted neck pain (RR 2.35), right or left shoulder pain (RR 2.45 and 1.64). These results suggest that both peak and cumulative discomfort could predict future musculoskeletal pain.     

Musculoskeletal disorder prevalence and psychosocial risk exposures by age and gender in a cohort of office based employees in two academic institutions

This study presents data on self-reported prevalence of Musculo-Skeletal Disorder (MSD) symptoms and psychosocial risk exposures by age and gender among a group of office based University workers who use their computers for at least 25% of their workday. Employees in two academic organisations received an invitation to participate in an on-line questionnaire. A total of n = 852 office workers participated in this study; yet respondents who were employed for greater than 12 months were only included in the study cohort. Furthermore, participants were only considered for further analysis if they spent 50% or more of their workday in their office, and of this time at least 50% was spent on computer work (n = 569). The study indicates that self-reported symptoms of MSDs for these workers were highest in the neck, shoulder and lower back. Neck, shoulder and back MSDs were higher for females than males, yet age differences within genders were not evident for these symptoms. For neck disorders, symptomatic individuals reported significantly higher levels of office work (p < 0.05) and PC usage (p < 0.005), and significantly lower levels of job content (p < 0.01), job demands (p < 0.05), and work environment (p < 0.05) compared to asymptomatic participants. For the shoulder, symptomatic individuals exposure levels were significantly higher for office work (p < 0.05) and PC usage (p < 0.05) and significantly lower for job content (p < 0.05) compared to asymptomatic individuals. There was evidence of important differences in the psychosocial exposures between age and genders, but associations between these differences and MSD symptoms were not present.Relevance to industryThis study presents prevalence data on age and gender differences in self-reported symptoms of MSDs and psychosocial risk exposures in a group of sedentary workers.     

Self-reported neck symptoms and use of personal computers,laptops and cell phones among Finns aged 18–65

The purpose of this study was to investigate the possible relation between self-reported neck symptoms (aches, pain or numbness) and use of computers/cell phones. The study was carried out as a cross-sectional study by posting a questionnaire to 15,000 working-age persons, and 15.1% of all respondents (6121) reported that they very often experienced physical symptoms in the neck. The results showed that they also had many other symptoms very often, and 49% used a computer daily at work and 83.9% used cell phones. We compared physical/mental symptoms of persons with symptoms in the neck quite often or more, with others. We found significant differences in the physical/mental symptoms and use of cell phones and computers. The results suggest taking into account in the future that those persons' symptoms in the neck can be associated with use of cell phones or computers.

Practitioner Summary: We investigated the possible relation between neck symptoms and use of computers/cell phones. We found that persons, who very often had symptoms in the neck, had also other symptoms very often (e.g. exhaustion at work). Their use of information and communication technology (e.g. computers) can associate with their symptoms.