Documents computer mouse 10 results

"This study attempted to identify risk factors for musculoskeletal symptoms in the neck and hand-wrist regions among employees using computers at work.Men's and women's previous symptoms, women's low influence at work and high-placed computer screen, and men's short time in the same job and good computer skills were associated with neck symptoms. Hand-wrist symptoms were predicted by previous symptoms and low influence at work for both the men and women and sensorial demands for the women only. The duration of computer use predicted hand-wrist symptoms {eg, odds ratio [OR] of 2.3 [95% confidence interval (95% CI) 1.2-4.3] for almost continual computer use}, but not neck symptoms. For those with almost continual computer use, hand-wrist symptoms were associated with mouse use for at least half of the worktime (OR 4.0, 95% CI 1.0-15.5] and not using the mouse at all (OR 4.0, 95% CI 1.1-14.4), as compared with mouse use for one-fourth of the worktime.Limiting computer use to less than three-fourths of the worktime would help to prevent hand-wrist symptoms. Furthermore, low influence at work predicts both neck and hand-wrist symptoms."

Objectives The purpose of this study was to develop and validate a sampling strategy for characterizing the finger force exposures associated with computer mouse use. Methods Mouse forces were measured from 16 subjects (8 men, 8 women), on 3 separate days, at their actual workstations while they performed (i) their regular work, (ii) a battery of standardized tasks, and (iii) simulated mouse use. Results The forces applied to the mouse did not vary between hours or days. During regular work, the mouse was used 78.0 (SD 40.7) times per hour, accounting for 23.7 (SD 9.5)% of the worktime. The mean forces applied to the sides and button of the mouse were low, averaging 0.6 % of the maximal voluntary contraction (%MVC) (0.43 N) and 0.8 % MVC (0.35 N), respectively. The forces applied to the mouse during the standardized tasks differed from the regular work forces; however, there were moderate-to-strong correlations between the 2 measures. Conclusions With respect to performing exposure assessment studies, the 3 major findings were (i) mouse force measurements should be made while subjects perform their actual work in order to characterize the absolute applied force accurately, (ii) the forces applied to the mouse during the performance of a short battery of standardized tasks can be used to characterize relative exposure and identify computer operators or work situations for which higher forces are applied to the mouse, and (iii) subjects cannot accurately simulate mouse forces.

"The electromyographic (EMG) activity of shoulder and forearm muscles was recorded during a standardized computer task with different combinations of time pressure, precision demands, and mental demands to study the interaction of these factors and their effect on muscular response during simulated computer work. The interaction between work pace and other exposure factors must be taken into account when the effects of changes in exposure demands on muscular response are predicted. Only then can it be predicted whether changing demands will constitute a risk of developing musculoskeletal disorders."

"Computer-mouse work is characterized by repetitive movements combined with mental demands. The present purpose was to study how the body responded to simulated Computer Aided Design (CAD) work without memory demand and when a high short-term memory demand was introduced. Nine female subjects repetitively performed a task which involved 15 s of elevation of the right index and middle fingers followed by 6 s of rest. Every second time the fingers rested, the left index finger was required to type a six-figure number, either '123456' (without memory demand) or a random number shown half a minute before (with memory demand). After 7 min of performing the task without memory demand, the memory demand was introduced and continued for 1 h. Introduction of memory demand resulted in increased heart rate (77-->84 beats/min), blood pressure (systolic 129-->140 mmHg; diastolic 72-->79 mmHg) and forearm extensor muscle activity (wrist, 2.7-->4.5% EMGmax; finger, 5.6-->7.5% EMGmax) and finger flexor muscle activity (0.7-->1.2% EMGmax) indicating increased co-contraction. Hereafter, muscle activity and cardiovascular response tended to decrease. Self-reported stress and rating of perceived exertion (RPE) for the right shoulder increased throughout the period. Two additional sub-studies were inlcuded, which focused on adaptation to the physical load, showing a decrease in muscle activity and arousal, and reintroduction of the memory load, showing a lower response as compared to the initial response. The practical consequences of the findings suggest that job content should have variable mental demands."

Computer mouse use has become an integral part of office work in the past decade. Intensive mouse use has been associated with increased risk of upper extremity musculoskeletal disorders, including carpal tunnel syndrome. Sustained, elevated fluid pressure in the carpal tunnel may play a role in the pathophysiology of carpal tunnel syndrome. Carpal tunnel pressure was measured in 14 healthy individuals while they performed tasks using three different computer mice. Participants performed a multidirectional dragging ('drag and drop') task starting with the hand resting (static posture) on the mouse. With one mouse, an additional pointing ('point-and-click') task was performed. All mice were associated with similar wrist extension postures (p=0.41) and carpal tunnel pressures (p=0.48). Pressures were significantly greater during dragging and pointing tasks than when resting the hand (static posture) on the mouse (p=0.003). The mean pressures during the dragging tasks were 28.8- 33.1 mmHg, ~ 12 mmHg greater than the static postures. Pressures during the dragging task were higher than the pointing task (33.1 versus 28.0 mmHg), although the difference was borderline non-significant (p=0.06). In many participants the carpal tunnel pressures measured during mouse use were greater than pressures known to alter nerve function and structure, indicating that jobs with long periods of intensive mouse use may be at an increased risk of median mononeuropathy. A recommendation is made to minimize wrist extension, minimize prolonged dragging tasks and frequently perform other tasks with the mousing hand.

"Presents the findings from a two-year study investigating health problems associated with the use of non-keyboard input devices (NKID). The research used a combination of methods to determine the extent to which different NKID are currently in use, how they are used and problems that result. Evidence was collected through a literature review; questionnaire survey of 128 IT and health and safety managers; workplace assessments involving interviews and observation with 45 users across 9 different companies; a questionnaire survey of 848 users (3500 questionnaires issued, 24% response rate); and laboratory work including an expert assessment of different devices, a laboratory trial comparing traditional and L- shaped desks with three different arm support conditions, and a case study investigating touch screen use. Stresses the importance of an ergonomics approach in risk reduction, a method that looks at the user-computer interaction as a whole, the aim being to fit the work to the person, rather than the person to the work. Recommends a systematic risk assessment for NKID with the following considerations: nature of the task, including software design; NKID design and operation; workstation configuration; working environment; work organisation; training; cleaning and maintenance; procedures for musculoskeletal health monitoring; specific needs of individual users (e.g. those with existing health problems)."

"Workplace stressors have been indicated to play a role in the development of neck and upper extremity pain possibly through an increase of sustained (low-level) muscle activity. The aim of this review was to study the effects of workplace stressors on muscle activity in the neck-shoulder and forearm muscles. An additional aim was to find out whether the muscles of the neck-shoulder and the forearm are affected differently by different types of workplace stressors. A systematic literature search was conducted on studies investigating the relation between simulated or realistic workplace stressors and neck-shoulder and forearm muscle activity. For studies meeting the inclusion criteria, a risk of bias assessment was performed and data were extracted for synthesis. Results were pooled when possible and otherwise described. Twenty-eight articles met the inclusion criteria, reporting data of 25 different studies. Except for one field study, all included studies were laboratory studies. Data of 19 articles could be included in the meta-analysis and revealed a statistically significant, medium increase in neck-shoulder and forearm muscle activity as a result of workplace stressors. In subgroup analyses, we found an equal effect of different stressor types (i.e. cognitive/emotional stress, work pace, and precision) on muscle activity in both body regions. In conclusion, simulated workplace stressors result in an increase in neck-shoulder and forearm muscle activity. No indications were found that different types of stressors affect these body regions differently. These conclusions are fully based on laboratory studies, since field studies on this topic are currently lacking."