Documents shoulder 40 results

The incidence of upper-limb, neck-shoulder, and low-back disorders and their induction times were investigated among new workers in tasks with various physical workloads.New trailer assemblers (N=364) were followed prospectively for 45 months - the workers' health status via medical records and exposure to physical workload factors via job titles, walk-throughs, task descriptions, and some direct measurements. The incidence rate of first sick leave due to such disorders was calculated for different workload groups. The proportion of workers surviving without musculoskeletal disorders was estimated by the Kaplan-Maier product-limit estimator, and the effect of the exposure on the risk of incident disorders was estimated with the Cox proportional hazards model.The highest annual incidences were observed for strenuous tasks, the incidence rate for men being 16.8 per 100 person-years [95% confidence interval (95% CI) 8.0-30.9] for upper-limb disorders in strenuous tasks and 6.1 (95% CI 2.0-14.1) in nonstrenuous tasks and that for women being 32.0 (95% CI 11.7-69.7) and 9.9 (95% CI 0.2-54.9), respectively. The men's risk of contracting an upper-limb or neck-shoulder disorder in strenuous tasks was about threefold [hazard ratio (HR) 3.2 (95% CI 1.1-9.4) for upper-limb disorders and 2.7 (95% CI 0.9-8.1) for neck-shoulder disorders] that of nonstrenuous tasks, whereas workload seemed not to affect low-back disorders. The workers first sought medical advice for their disorders typically some months after employment began.Newly employed workers in hand-intensive tasks have a high risk of upper-limb and neck-shoulder disorders. An etiologic role for activities involving high force demands in upper-limb and neck-shoulder disorders is possible.

For years scientists have kept saying that elevated postures of the arm are a risk factor for shoulder disorders, but it is not known how much elevation and for how long is too much (1). Others have called for more precision in exposure assessment in epidemiologic studies, emphasizing the importance of the intensity, frequency, and duration of exposures (2). The article by Punnett and her co-workers (3) on shoulder disorders in this issue of the Scandinavian Journal of Work, Environment & Health is important for practitioners and scientists in occupational health and ergonomics, and also for others involved in the prevention of musculoskeletal disorders. This study found a dose-response relationship between the duration of severe shoulder flexion or abduction as a proportion of cycle time and shoulder disorders. The risk was clearly increased for severe shoulder flexion or abduction (>90 degrees) for less than 10% of the cycle time, and it increased when the proportional duration was 10% or more. The authors made considerable effort to assess also forces imposed on the shoulder joint and used a biomechanical model to incorporate posture and hand loads into a common metric of force. They failed, however, to show an elevated risk for force, probably because the worktasks used in this study did not involve the exertion of high forces. The repetition rate of arm movements was also observed. But it correlated strongly with shoulder elevation, and its effects could not therefore be distinguished. The strength of this study is its objective assessment of its outcome and exposure. Not all the cases had positive clinical findings, but the risk estimates were slightly higher for those with clinical findings, and the results therefore suggested an even stronger association between clinically manifest disease and postural load. The exposure assessment included the intensity, frequency, and duration of shoulder postures and resulted in a multitude of data that required careful data reduction and analysis. The history of epidemiologic studies on shoulder disorders is short, not really starting until some 20 years ago, when a group of studies on shipyard welders was published that showed a high prevalence of shoulder disorders (4). Overhead welding was considered the main work-related factor. Later, studies among bricklayers and rockblasters showed an association between acromioclavicular arthrosis and cumulative exposure to physical loads, such as the sum of lifted tonnes during worklife (5). In the same group of workers, shoulder tendinitis was associated with cumulative vibration dose (6). A recent study found the prevalence of shoulder impingement syndrome to be higher among current and former slaughterhouse workers than in a comparison group. Video recordings of a group of the slaughterhouse workers showed that they spent half of their worktime with arm elevation of ?30 degrees (7). There are no prospective studies on clinically defined shoulder disorders. The study by Punnett and her co-workers seems to be among the most rigorous available on the association between shoulder disorders and physical workload factors. The results will be useful in the primary and secondary prevention of shoulder disorders. For monotask jobs, the results can be considered a source of reference values for the proportional duration of overhead work. The proportional durations can also be translated into minutes or hours of shoulder flexion or abduction per day. As there are very few similar data with which to compare the results of Punnett and her co-workers' study, it is obvious that more studies are needed. At this point we can also question how much further epidemiologic studies will take us. We could probably learn more about, for example, hand loads or forces imposed on the shoulder joint with a worker population that is exposed to a wider range of forces. Other types of tasks could give us more information about the repetition rates of shoulder movements. Such studies as this one bring us to the contact surface between epidemiologic and experimental research; more information on shoulder postures, hand loads, arm movement frequencies, and their combinations can be obtained largely in the laboratory. But, as we all know, we are unlikely to have a clinically relevant health outcome in the laboratory. Reference values can then be subjected to further reasoning by collecting the best available epidemiologic and experimental data and looking for patterns of dose-response between exposures and outcomes and interactions between exposures.

"OBJECTIVE: This study aimed to test longitudinal associations linking the work-unit-level psychosocial and organizational work environment and biomechanical constraints to workers' shoulder pain in the French multi-centre cohort ORSOSA study of registered nurses (RN) and nursing assistants (NA).
METHODS: We analyzed 1896 female RN and NA, who were free of shoulder pain in 2006 and in the same position and work unit in 2008. Incident shoulder pain (SP) was defined as self-reported pain that persists for ≥ 4 days and/or increases during a lateral movement of the arm away from the midline of the body (abduction). Both cross-sectional and longitudinal models were built to test if work-unit-level features or their influences on both work tasks and individual perception of the work environment directly influence the risk of developing incident SP.
RESULTS: RN in work units with understaffing issues or poor relationships reported higher levels of biomechanical constraints in movements and postures and a lower level of perceived job security and stability. NA who experienced such issues reported higher levels of biomechanical constraints in indirect patient-handling activities only. The exposure to these latter factors was associated with higher two-year incident SP among workers.
CONCLUSION: This study shows that the work-unit-level organizational characteristics may impact workers' musculoskeletal disorders by conditioning both work-task-related biomechanical exposures and individual perception of the working environment. In healthcare settings, primary prevention programs to reduce MSD would benefit from a focus on work unit level exposures."

"The aim of this prospective study was to detect a possible development of trapezius myalgia likely to be work-related in initially healthy female packers. Symptoms were recorded on a five-step intensity scale in a daily diary and in an interview at ten-week intervals. All of the subjects were interviewed concerning assumed risk factors during work and leisure time, and a clinical examination was performed. Within their first year of employment, 17 of 30 subjects developed work-related trapezius myalgia of sufficient intensity to be classified as patients. The median time before a clinically confirmed patient status was 23 (range 6-51) weeks. The symptoms showed a fluctuating pattern, decreasing on the weekends and during some holidays. In conclusion, likely work-related trapezius myalgia of a nonchronic character showed a high one-year cumulative incidence at a plant with repetitive light work."

"Introduction

This study aims to investigate the relationship between work-related physical and psychosocial characteristics and complaints of the neck, shoulder and forearm/hands. Methods

Data were used from a prospective Dutch cohort study among computer office workers with a follow-up period of 2 years. The study was conducted among 264 computer users. Physical and psychosocial risk factors were tested to predict the occurrence of neck, shoulder and forearm/hands complaints. Bivariate and multivariable logistic regression was used to identify the association between risk factors and outcome variables.

Results

The 2 year follow-up prevalence rates with 95% CI for neck complaints were 0.31 (0.28–0.37), for shoulder complaints 0.33 (0.27–0.39) and for forearm/hands complaints 0.21 (0.14–0.28). Four main predictors for the occurrence of neck and shoulder complaints were identified: (1) Irregular head and body posture [OR: 1.1 (1.0–1.2) P = 0.04]; (2) task difficulty (job demands) [OR: 1.2 (1.0–1.5) P = 0.01]; (3) number of working hours/day with the computer [OR: 1.20 (1.0–1.4) P = 0.03]; and (4) having had a previous history of complaints [OR: 7.2 (3.8–13.2) P = 0.01]. Two predictors were identified for forearm/hands complaints: time pressure (job demands) [OR: 1.20 (1.0–1.4) P = 0.03] and having had a previous history of complaints [OR: 7.1 (3.5–14.1) P = 0.06].

Conclusion

This longitudinal study suggests that risk factors of upper musculoskeletal complaints in computer workers consist of a mixture of physical and psychosocial characteristics."

"This study investigated delivery scenarios of service drivers working in the retail meat industry. The methodology included analysis of accident reports, and field investigations of deliveries at craft-butcher shop premises, including semi-structured interviews with managers and workers. The findings provide greater clarity about the hazards in this job, and suggest for peripatetic delivery activities, four main factors on which decisions about risk and good practice may be made: composition of the orders; characteristics of the delivery vehicle/truck; handling method most often used; and, the road/access conditions."

"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 4th 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."

"The task of wall painting produces considerable risk to the workers, both male and female, primarily in the development of upper extremity musculoskeletal disorders. Insufficient information is currently available regarding the potential benefits of using different paint roller designs or the possible adverse effects of painting at different work heights. The aim of this study was to investigate the influence of gender, work height, and paint tool design on shoulder muscle activity and exerted forces during wall painting. Ten young adults, five male and five female, were recruited to perform simulated wall painting at three different work heights with three different paint roller designs while upper extremity muscle activity and horizontal push force were recorded. Results demonstrated that for female participants, significantly greater total average (p = 0.007) and integrated (p = 0.047) muscle activity was present while using the conventional and curly flex paint roller designs compared to the proposed design in which the load was distributed between both hands. Additionally, for both genders, the high working height imposed greater muscular demands compared to middle and low heights. These findings suggest that, if possible, avoid painting at extreme heights (low or high) and that for female painters, consider a roller that requires the use of two hands; this will reduce fatigue onset and subsequently mitigate potential musculoskeletal shoulder injury risks."