Therese Nordberg Hanvold

Computer work and musculoskeletal disorders of the neck and upper extremity: a systematic review.

BackgroundThis review examines the evidence for an association between computer work and neck and upper extremity disorders (except carpal tunnel syndrome).MethodsA systematic critical review of studies of computer work and musculoskeletal disorders verified by a physical examination was performed.ResultsA total of 22 studies (26 articles) fulfilled the inclusion criteria. Results show limited evidence for a causal relationship between computer work per se, computer mouse and keyboard time related to a diagnosis of wrist tendonitis, and for an association between computer mouse time and forearm disorders. Limited evidence was also found for a causal relationship between computer work per se and computer mouse time related to tension neck syndrome, but the evidence for keyboard time was insufficient. Insufficient evidence was found for an association between other musculoskeletal diagnoses of the neck and upper extremities, including shoulder tendonitis and epicondylitis, and any aspect of computer work.ConclusionsThere is limited epidemiological evidence for an association between aspects of computer work and some of the clinical diagnoses studied. None of the evidence was considered as moderate or strong and there is a need for more and better documentation.

A Prospective Study of Neck, Shoulder, and Upper Back Pain Among Technical School Students Entering Working Life

PURPOSE The aim of this prospective study was to relate the prevalence of neck, shoulder, and upper back pain to occupational and individual risk factors among a population of technical school students in their transition from school to working life. In addition, we wanted to assess the changes in pain prevalence during follow-up. METHODS A cohort consisting of 173 technical school students was followed up during a 3-year period, from their last year of school through their first years of working life. Data on self-reported neck, shoulder, and upper back pain and factors such as mechanical exposure, perceived stress, and physical activity in leisure time were collected. RESULTS A high prevalence of pain in the neck, shoulder, and upper back among the technical school students was found. There were however few students reporting severe pain. Reporting pain at baseline gave over three times higher risk of reporting it at follow-up. A high level of physical activity outside working hours gave a lower risk of reporting neck, shoulder, and upper back pain at follow-up. High and moderate levels of mechanical exposure and high stress level were not found to be risk factors for pain after entering working life. CONCLUSION Neck, shoulder, and upper back pain are common among adolescents and may persist into working life. These results may give potential for preventive efforts at a young age. There is still much uncertainty about the factors leading to musculoskeletal pain, and more research is needed on this topic.

The effect of work-related sustained trapezius muscle activity on the development of neck and shoulder pain among young adults

OBJECTIVE This study aimed to evaluate if sustained trapezius muscle activity predicts neck and shoulder pain over a 2.5-year period. METHODS Forty young adults (15 hairdressers, 14 electricians, 5 students and 6 with various work) were followed during their first years of working life. Self-reported neck and shoulder pain during the last four weeks was assessed seven times over the observational period. Upper-trapezius muscle activity was measured during a full working day by bilateral surface electromyography (EMG) at baseline (winter 2006/7). Sustained trapezius muscle activity was defined as continuous muscle activity with amplitude >0.5% EMGmax lasting >4 minutes. The relative time of sustained muscle activity during the working day was calculated and further classified into low (0-29%), moderate (30-49%) and high (50-100%) level groups. RESULTS Generalized estimating equations (GEE), adjusted for time, gender, mechanical workload, control-over-work intensity, physical activity, tobacco use, and prior neck and shoulder pain, showed that participants with a high level of sustained muscle activity had a rate of neck and shoulder pain three times higher than the low level group during a 2.5-year period. The association was strongest at the same time and shortly after the EMG measurement, indicating a time-lag of ≤6 months. CONCLUSION The results support the hypothesis that sustained trapezius muscle activity is associated with neck and shoulder pain. This association was strongest analyzing cross-sectional and short-term effects.

Occupational posture exposure among construction electricians.

The aim of this study is to record, objectively describe and compare working postures of Brazilian and Norwegian construction electricians. Postures of the upper arms, head, and neck during work and breaks were quantified by means of inclinometry for a representative sample of 12 Brazilian and 12 Norwegian electricians in the construction industry during a full work-shift. Despite that differences were found between specific work-related factors, Brazilian and Norwegian workers revealed a high and very similar level and pattern of postures for all evaluated body regions, suggesting that results could be extrapolated to other electricians. Upper arm elevation was high and similar for both groups and head flexion and extension was pronounced compared to other occupations. Thus, extreme postures were identified for construction electricians in both countries, with similar exposure pattern also for defined tasks (planning, support and wiredraw), suggesting that this job is risky regardless organizational differences.

Work with prolonged arm elevation as a risk factor for shoulder pain: A longitudinal study among young adults

This prospective study aimed at examining if work with prolonged arm elevation predicts shoulder pain among 41 young adults in their first years of working life. Fifteen hairdressers, 15 electricians, 5 students and 6 with various work were followed over a 2.5-year period (2006/7-2009). Arm elevation was measured with inclinometers during a full working day at baseline. Shoulder pain was reported at baseline and twice in the follow-up period. Data were analyzed by generalized estimating equations (GEE-analysis), stratified by gender and adjusted for time, mechanical workload, work demand, physical activity, tobacco use and prior shoulder pain. Work with prolonged arm elevation with angles >60° and >90° were associated with shoulder pain among women. Even though the shoulder pain levels are low the study suggests work with arms elevated as an early work-related risk factor among women, and indicates the importance of early prevention strategies.

Long periods with uninterrupted muscle activity related to neck and shoulder pain.

The aim was to analyze the relationship between periods with uninterrupted neck muscle activity for ≥ 4 min and neck and shoulder pain. The trapezius muscle activity was recorded bilaterally on 40 young workers and students during a full shift. Neck and shoulder pain, mechanical work load and decision control were reported at the same time as the muscle activity recording and 6 months later. A dose-response relationship was found between uninterrupted muscle activity and neck and shoulder pain, with a ten-fold higher risk for the group with more than half, compared to less than a third, of the shift with uninterrupted muscle activity. Self-reported mechanical work load showed a small but protective effect related to pain. Gender and decision control did not emerge as important risk factors in this model. In conclusion, this study indicates that work or other exposures that contains long periods with uninterrupted neck muscle activity of 4 min duration or longer should be minimized to reduce risk of neck and shoulder pain.

A longitudinal study on risk factors for neck and shoulder pain among young adults in the transition from technical school to working life

OBJECTIVES The study examined the course of neck and shoulder pain among a cohort of technical school students entering working life. We also aimed to identify work-related and individual risk factors for neck and shoulder pain during this transition period. METHODS The study was designed as a prospective cohort study following 420 technical school students (167 student hairdressers, 118 student electricians, and 135 media/design students) from school, through their apprenticeship and into working life. Every 4 (th)month over a 6.5 year period (2002-2009), the participant`s neck and shoulder pain for the preceding four weeks was assessed. Mechanical and psychosocial workplace factors as well as individual factors were evaluated at baseline and/or during the follow-up period. Data were analyzed by generalized estimating equations (GEE). RESULTS We found a significant increase in neck and shoulder pain over time in the transition from technical school to working life. High mechanical workload was associated with neck and shoulder pain among women, while a high level of shoulder muscle endurance capacity was associated with lower rates of neck and shoulder pain among men. Perceived muscle tension and ethnicity were the most consistent predictors for neck and shoulder pain, found among both women and men. CONCLUSION Increased neck and shoulder pain was found in the transition from technical school to working life, and both work-related and individual factors were associated with pain development.

Vocational muscle activity and perceived muscle tension in young adults

Abstract Purpose: To study the association between muscle rest of vocational electromyographic (EMG) recordings and perceived muscle tension, and whether this association is modified by limiting the EMG measure to pauses from active work. Methods: A muscle rest measure was calculated in a whole workday EMG recording of the upper trapezius muscles, as well as during pauses from active work in 19 males and 23 females (mean age 22 years, range 20–25). Self-reports on muscle tension habits and the covariates neck and shoulder pain, perceived stress level, and leisure time physical activity were collected in a questionnaire. Results: The muscle rest measure showed a moderate negative correlation with the subjects’ perceived muscle tension. This association became somewhat stronger and statistically significant when the EMG measure was restricted to the pauses from active work. Conclusions: Perceived muscle tension is associated to trapezius EMG muscle rest during pauses from active work.

Perceived tension and relaxation ability in young adults

Abstract Purpose: To study the association between self-reported general tension and muscle tension, and clinically tested relaxation ability. Methods: Self-reports on muscle tension habits and on general tension, and the covariates neck and shoulder pain, perceived stress level, perceived mastery of work, quantitative work demands, and leisure time physical activity, were collected on a questionnaire (52 males, 81 females, mean age 23 years). A clinical test on relaxation ability was performed by a trained physiotherapist on a subsample (38 males, 39 females). Results: Perceived general tension showed a highly significant (p < 0.001) correlation with the muscle tension habit score (0.58), and the muscle tension factor (0.54). None of the self-reported tension measures correlated with the relaxation ability score. The self-reported tension measures, but not the clinical tension score, showed an association with neck and shoulder pain and perceived stress level. Conclusions: The self-reported measures of general tension and of muscle tension correlated and probably represented similar phenomenon. However, the subjects’ perceived stress level was to a higher degree reflected in the measure of general tension. The score of the clinical test on relaxation ability did not show an association with the self-reported tension measures.

1410 Cause-specific sickness absence by occupation

Introduction To identify workers facing particular challenges related to occupational exposure and health is valuable, as work environment plays an important role in terms of sickness absence (SA) and return to work. Assessing vulnerable occupational groups related to SA may facilitate decision makers in terms of allocating resources and interventions. The aim of this paper was to assess cause-specific SA rates by occupation and evaluate occupational specific excess fractions for SA. Methods The source population was a Norwegian birth cohort (all 626 928 live-born individuals born between 1967 and 1976). Individual records on physician-diagnosed SA spells lasting >16 calendar days were obtained from the Norwegian event database FD-Trygd. The incidence rate of SA was estimated annually during 2005–2009. SA with musculoskeletal and mental diagnoses, was estimated for 31 occupational groups classified by ISCO-88 on a 2-digit level. Excess cause-specific SA was also estimated for each of the 31 occupations. All analyses were stratified by gender. Result Workers in sales and service occupations and metal and machinery workers had the highest annual rates of musculoskeletal SA. Male metal and machinery workers had a 91% increased rate, compared to male corporate managers, while female workers in sales and services occupations had an 83% increased rate, compared to female corporate managers. For SA related to mental disorders, personal care workers had the highest rates among both men and women. Discussion Occupation is an imprecise measure of work exposure and in the continued work on these data we will use a newly developed job exposure matrix to estimate the associations between specific physical and psychosocial exposures and cause-specific sickness absence by occupation.