Musculoskeletal disorders in demanding computer work - with air traffic control as a model

In computer work, musculoskeletal disorders are frequently reported, but the knowledge about causal relationships is limited. In air traffic control, female and male operators perform exactly the same computer work. Introduction of a new computer system implied a momentary change from a “varied” system containing different in-put devices, to a system characterized by intensive mouse-work. The effect of the change on the physical exposure was studied, as well as the musculoskeletal health before and after the change. In addition, gender differences and psychosocial factors were assessed. The physical workload, recorded in 14 subjects in both systems by technical measurements of postures, movements and muscular load, showed large differences: The mouse-intensive system was associated with lower movement velocities, less varying postures and less rest in the right forearm extensor muscles. The differences were amplified at high work intensity. Neck postures in females with neck/shoulders/upper back disorders were compared to those in healthy referents, but without significant differences. Musculoskeletal disorders in neck and upper limbs were assessed by standardised physical examinations in 148 air traffic controllers (71 women and 77 men) and the psychosocial work environment by questionnaire. Disorders in elbows/hands increased significantly after 20 months of work in the mouse-intensive system, while in neck/shoulders/upper back, there was no consistent change. There was no gender difference in elbows/hands disorders, while the females were at higher risk in neck/shoulders/upper back. Disorders in elbows/hands were not explained by psychosocial factors. Most likely, these findings are applicable to similar technological developments in other settings

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

<p>Abstract</p> <p>Background</p> <p>This review examines the evidence for an association between computer work and neck and upper extremity disorders (except carpal tunnel syndrome).</p> <p>Methods</p> <p>A systematic critical review of studies of computer work and musculoskeletal disorders verified by a physical examination was performed.</p> <p>Results</p> <p>A 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.</p> <p>Conclusions</p> <p>There 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.</p

Gender and Posture are Significant Risk Factors to Musculoskeletal Symptoms during Touchscreen Tablet Computer Use

[Purpose] To investigate the prevalence of neck and shoulder symptoms during the use of tablet computer, and to identify the risk factors associated with these symptoms. [Subjects and Methods] A cross-sectional survey was conducted to study tablet computer usage, posture during use, and neck and shoulder symptoms in 412 participants in a school setting. Significant risk factors for musculoskeletal symptoms during tablet computer use were identified. [Results] Overall prevalence of musculoskeletal symptoms during tablet computer use was 67.9% with greater prevalence of neck symptoms (neck: 84.6%; shoulder/upper extremity: 65.4%). Significant risk factors associated with symptoms during use were: current musculoskeletal symptoms, gender, roles, and postural factors including: sitting without back support, sitting with device in lap, and lying on the side and on the back during tablet computer use. A multivariate analysis further showed that the odds for females to have symptoms were 2.059 times higher than males. [Conclusion] The findings revealed that female gender and other postural factors were significantly associated with musculoskeletal symptoms during the use of tablet computer. Among all postural factors, sitting without back support was identified as the most important risk factor for having musculoskeletal symptom

Combining brain-computer interfaces and assistive technologies: state-of-the-art and challenges

In recent years, new research has brought the field of EEG-based Brain-Computer Interfacing (BCI) out of its infancy and into a phase of relative maturity through many demonstrated prototypes such as brain-controlled wheelchairs, keyboards, and computer games. With this proof-of-concept phase in the past, the time is now ripe to focus on the development of practical BCI technologies that can be brought out of the lab and into real-world applications. In particular, we focus on the prospect of improving the lives of countless disabled individuals through a combination of BCI technology with existing assistive technologies (AT). In pursuit of more practical BCIs for use outside of the lab, in this paper, we identify four application areas where disabled individuals could greatly benefit from advancements in BCI technology, namely,“Communication and Control”, “Motor Substitution”, “Entertainment”, and “Motor Recovery”. We review the current state of the art and possible future developments, while discussing the main research issues in these four areas. In particular, we expect the most progress in the development of technologies such as hybrid BCI architectures, user-machine adaptation algorithms, the exploitation of users’ mental states for BCI reliability and confidence measures, the incorporation of principles in human-computer interaction (HCI) to improve BCI usability, and the development of novel BCI technology including better EEG devices

Prevalence and Risk Factors for Neck and Shoulder Musculoskeletal Symptoms in Users of Touch-Screen Tablet Computers

Background and Purpose: Neck and upper extremity symptoms are common health complaints in the general population and cause a substantial financial burden to the health care system. Neck pain is known to be a multi factorial disorder, with head and spinal posture being one of the most important factors. Currently there is little evidence showing a relationship between touch-screen tablet computer usage and neck/upper extremity pathologies. However, it is fair to postulate that the incidence of neck/upper extremity pathologies is higher within touch-screen tablet computer users, considering how users maintain static postures while using the device. The primary purposes of the current study were to 1) investigate the prevalence of neck and shoulder symptoms and potential risk factors, 2) identify risk factors associated with symptoms during device use, especially in sitting postures. The secondary purpose was to investigate gender differences in device usage behavior, symptoms, and postural factors. Subjects: A cross-sectional survey study was conducted in a population of university students, staff, faculty, and alumni (N = 412). Methods and Results: Prevalence of symptoms during device use was 67.9 %. Most symptoms were reported in the neck (84.6%) and upper back/shoulder areas (65.4%). With sitting postures, significant symptoms during tablet use included sitting without back support (p= 0.016) and sitting with device in the lap (p= 0.002) based on Chi-square analyses. A multiple logistic regression analysis further demonstrated that female gender (p=0.004) and sitting in a chair without back support (p=0.006) are the predictors of experiencing symptoms during the use of tablets. For other general postures, the significant factors are lying on the side (p= 0.002) and lying on the back (p= 0.016) during tablet use. Furthermore, our results showed that 70.1% of the female respondents reported to have musculoskeletal symptoms during device usage, in comparison to 29.9% of the male respondents (p= 0.019). Additionally, women (75.7%) demonstrated significantly more symptoms at the upper back and shoulder regions than men (24.3%) (p = 0.014)

Achieving workplace inclusiveness by using ergonomics risk assessment

Traditional manufacturing work practices do not consider human variability issues during the design process. However, most manual assembly activities demand high levels of repetition and speed without compromising product quality and work productivity. Individual factors including age, gender, skill, experience and anthropometry cause variations in task strategies that lead to variations in individual and organizational work performance. The ergonomics-based risk assessment methods OWAS, REBA and RULA have been used to evaluate risk levels associated with working methods. This paper discusses the need for these methods to understand and highlight the key issues generated by these variations with the objective of minimizing these variations. Methods that can be used to promote working strategies that minimize the level of risk are described. The proposed research method potentially reduces work-related musculoskeletal disorders, injuries, pain, and promotes safe, healthy, productive and more inclusive working strategies suitable for a diverse working population

An Assessment of Unmanned Aircraft System Pilot Discomfort and Fatigue

The rapid growth of unmanned aircraft system (UAS) use in both the military and civil sectors has uncovered an array of challenges within the field. In terms of human factors and ergonomics, the influence of the unique physical design of the control stations used to pilot the unmanned aircraft on local muscular fatigue and discomfort are of great concern. This study was conducted to assess the influence of two display configurations, Side-by-Side (SS) and Stacked (ST), and two chairs, Ergonomic (EC) and Captain’s (CC), on mean and median power frequencies, root mean square amplitude, posture, discomfort, workload, and seat pressure. Sixteen participants [age: 24.75 ± 2.96 years; gender: 4 female/ 12 male; height: 177.56 ± 9.09 cm; weight: 81.37 ± 16.43 kg] completed four, 2-hour simulated UAS flights for all chair/display combinations. Eight participants piloted one, 6-hour simulated UAS flight in the display/chair combination which best minimized discomfort and fatigue in the two-hour flights, EC/SS. During the two-hour flights, muscle activity, discomfort, posture, workload, and seat pressure findings indicated increased muscular fatigue and discomfort over time. Generally, the EC/SS condition appeared to best mitigate muscular fatigue and postures associated with increased risk for the development of musculoskeletal disorders. Six-hour flight data failed to provide additional insights on the influence of extended duration flights on the dependent variables of this study. Finally, linear regression analysis revealed muscle activity can likely be predicted during UAS piloting tasks using the dependent variables in this study; however, the study failed to provide evidence that models built from two-hour data can accurately predict muscle activity out to six hours