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Lind CM, Abtahi F, Forsman M. Wearable Motion Capture Devices for the Prevention of Work-Related Musculoskeletal Disorders in Ergonomics-An Overview of Current Applications, Challenges, and Future Opportunities. SENSORS (BASEL, SWITZERLAND) 2023; 23:s23094259. [PMID: 37177463 PMCID: PMC10181376 DOI: 10.3390/s23094259] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/14/2023] [Accepted: 04/22/2023] [Indexed: 05/15/2023]
Abstract
Work-related musculoskeletal disorders (WMSDs) are a major contributor to disability worldwide and substantial societal costs. The use of wearable motion capture instruments has a role in preventing WMSDs by contributing to improvements in exposure and risk assessment and potentially improved effectiveness in work technique training. Given the versatile potential for wearables, this article aims to provide an overview of their application related to the prevention of WMSDs of the trunk and upper limbs and discusses challenges for the technology to support prevention measures and future opportunities, including future research needs. The relevant literature was identified from a screening of recent systematic literature reviews and overviews, and more recent studies were identified by a literature search using the Web of Science platform. Wearable technology enables continuous measurements of multiple body segments of superior accuracy and precision compared to observational tools. The technology also enables real-time visualization of exposures, automatic analyses, and real-time feedback to the user. While miniaturization and improved usability and wearability can expand the use also to more occupational settings and increase use among occupational safety and health practitioners, several fundamental challenges remain to be resolved. The future opportunities of increased usage of wearable motion capture devices for the prevention of work-related musculoskeletal disorders may require more international collaborations for creating common standards for measurements, analyses, and exposure metrics, which can be related to epidemiologically based risk categories for work-related musculoskeletal disorders.
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Affiliation(s)
- Carl Mikael Lind
- IMM Institute of Environmental Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Farhad Abtahi
- Division of Ergonomics, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 141 57 Huddinge, Sweden
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Department of Clinical Physiology, Karolinska University Hospital, 141 86 Huddinge, Sweden
| | - Mikael Forsman
- IMM Institute of Environmental Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden
- Division of Ergonomics, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 141 57 Huddinge, Sweden
- Centre for Occupational and Environmental Medicine, Stockholm County Council, 113 65 Stockholm, Sweden
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Takács R, Kovács P, Ebeid RA, Almássy J, Fodor J, Ducza L, Barrett-Jolley R, Lewis R, Matta C. Ca2+-Activated K+ Channels in Progenitor Cells of Musculoskeletal Tissues: A Narrative Review. Int J Mol Sci 2023; 24:ijms24076796. [PMID: 37047767 PMCID: PMC10095002 DOI: 10.3390/ijms24076796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/01/2023] [Accepted: 04/04/2023] [Indexed: 04/08/2023] Open
Abstract
Musculoskeletal disorders represent one of the main causes of disability worldwide, and their prevalence is predicted to increase in the coming decades. Stem cell therapy may be a promising option for the treatment of some of the musculoskeletal diseases. Although significant progress has been made in musculoskeletal stem cell research, osteoarthritis, the most-common musculoskeletal disorder, still lacks curative treatment. To fine-tune stem-cell-based therapy, it is necessary to focus on the underlying biological mechanisms. Ion channels and the bioelectric signals they generate control the proliferation, differentiation, and migration of musculoskeletal progenitor cells. Calcium- and voltage-activated potassium (KCa) channels are key players in cell physiology in cells of the musculoskeletal system. This review article focused on the big conductance (BK) KCa channels. The regulatory function of BK channels requires interactions with diverse sets of proteins that have different functions in tissue-resident stem cells. In this narrative review article, we discuss the main ion channels of musculoskeletal stem cells, with a focus on calcium-dependent potassium channels, especially on the large conductance BK channel. We review their expression and function in progenitor cell proliferation, differentiation, and migration and highlight gaps in current knowledge on their involvement in musculoskeletal diseases.
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Affiliation(s)
- Roland Takács
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Patrik Kovács
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Rana Abdelsattar Ebeid
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, Semmelweis University, H-1428 Budapest, Hungary
| | - János Fodor
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - László Ducza
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Richard Barrett-Jolley
- Department of Musculoskeletal Biology, Faculty of Health and Life Sciences, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool L69 3GA, UK
| | - Rebecca Lewis
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK
| | - Csaba Matta
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
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Brambilla C, Lavit Nicora M, Storm F, Reni G, Malosio M, Scano A. Biomechanical Assessments of the Upper Limb for Determining Fatigue, Strain and Effort from the Laboratory to the Industrial Working Place: A Systematic Review. Bioengineering (Basel) 2023; 10:445. [PMID: 37106632 PMCID: PMC10135542 DOI: 10.3390/bioengineering10040445] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 03/24/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023] Open
Abstract
Recent human-centered developments in the industrial field (Industry 5.0) lead companies and stakeholders to ensure the wellbeing of their workers with assessments of upper limb performance in the workplace, with the aim of reducing work-related diseases and improving awareness of the physical status of workers, by assessing motor performance, fatigue, strain and effort. Such approaches are usually developed in laboratories and only at times they are translated to on-field applications; few studies summarized common practices for the assessments. Therefore, our aim is to review the current state-of-the-art approaches used for the assessment of fatigue, strain and effort in working scenarios and to analyze in detail the differences between studies that take place in the laboratory and in the workplace, in order to give insights on future trends and directions. A systematic review of the studies aimed at evaluating the motor performance, fatigue, strain and effort of the upper limb targeting working scenarios is presented. A total of 1375 articles were found in scientific databases and 288 were analyzed. About half of the scientific articles are focused on laboratory pilot studies investigating effort and fatigue in laboratories, while the other half are set in working places. Our results showed that assessing upper limb biomechanics is quite common in the field, but it is mostly performed with instrumental assessments in laboratory studies, while questionnaires and scales are preferred in working places. Future directions may be oriented towards multi-domain approaches able to exploit the potential of combined analyses, exploitation of instrumental approaches in workplace, targeting a wider range of people and implementing more structured trials to translate pilot studies to real practice.
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Affiliation(s)
- Cristina Brambilla
- Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato (STIIMA), Consiglio Nazionale delle Ricerche (CNR), Via Previati 1/E, 23900 Lecco, Italy
| | - Matteo Lavit Nicora
- Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato (STIIMA), Consiglio Nazionale delle Ricerche (CNR), Via Previati 1/E, 23900 Lecco, Italy
- Industrial Engineering Department, University of Bologna, 40126 Bologna, Italy
| | - Fabio Storm
- Bioengineering Laboratory, Scientific Institute, IRCCS “Eugenio Medea”, 23842 Bosisio Parini, Italy
| | - Gianluigi Reni
- Informatics Department, Autonomous Province of Bolzano, 39100 Bolzano, Italy
| | - Matteo Malosio
- Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato (STIIMA), Consiglio Nazionale delle Ricerche (CNR), Via Previati 1/E, 23900 Lecco, Italy
| | - Alessandro Scano
- Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato (STIIMA), Consiglio Nazionale delle Ricerche (CNR), Via Previati 1/E, 23900 Lecco, Italy
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Fan X, Lind CM, Rhen IM, Forsman M. Effects of Sensor Types and Angular Velocity Computational Methods in Field Measurements of Occupational Upper Arm and Trunk Postures and Movements. SENSORS 2021; 21:s21165527. [PMID: 34450967 PMCID: PMC8401405 DOI: 10.3390/s21165527] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/05/2021] [Accepted: 08/12/2021] [Indexed: 12/15/2022]
Abstract
Accelerometer-based inclinometers have dominated kinematic measurements in previous field studies, while the use of inertial measurement units that additionally include gyroscopes is rapidly increasing. Recent laboratory studies suggest that these two sensor types and the two commonly used angular velocity computational methods may produce substantially different results. The aim of this study was, therefore, to evaluate the effects of sensor types and angular velocity computational methods on the measures of work postures and movements in a real occupational setting. Half-workday recordings of arm and trunk postures, and movements from 38 warehouse workers were compared using two sensor types: accelerometers versus accelerometers with gyroscopes-and using two angular velocity computational methods, i.e., inclination velocity versus generalized velocity. The results showed an overall small difference (<2° and value independent) for posture percentiles between the two sensor types, but substantial differences in movement percentiles both between the sensor types and between the angular computational methods. For example, the group mean of the 50th percentiles were for accelerometers: 71°/s (generalized velocity) and 33°/s (inclination velocity)-and for accelerometers with gyroscopes: 31°/s (generalized velocity) and 16°/s (inclination velocity). The significant effects of sensor types and angular computational methods on angular velocity measures in field work are important in inter-study comparisons and in comparisons to recommended threshold limit values.
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Affiliation(s)
- Xuelong Fan
- IMM Institute of Environmental Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden; (X.F.); (I.-M.R.); (M.F.)
| | - Carl Mikael Lind
- IMM Institute of Environmental Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden; (X.F.); (I.-M.R.); (M.F.)
- Division of Ergonomics, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Hälsovägen 11C, SE-141 57 Huddinge, Sweden
- Correspondence:
| | - Ida-Märta Rhen
- IMM Institute of Environmental Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden; (X.F.); (I.-M.R.); (M.F.)
- Centre for Occupational and Environmental Medicine, Stockholm County Council, SE-113 65 Stockholm, Sweden
- Department of Industrial and Materials Science, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Mikael Forsman
- IMM Institute of Environmental Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden; (X.F.); (I.-M.R.); (M.F.)
- Division of Ergonomics, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Hälsovägen 11C, SE-141 57 Huddinge, Sweden
- Centre for Occupational and Environmental Medicine, Stockholm County Council, SE-113 65 Stockholm, Sweden
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Greco A. Spatial and Motor Aspects in the "Action-Sentence Compatibility Effect". Front Psychol 2021; 12:647899. [PMID: 33897555 PMCID: PMC8062728 DOI: 10.3389/fpsyg.2021.647899] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 03/16/2021] [Indexed: 11/13/2022] Open
Abstract
The Action-sentence Compatibility Effect (ACE) is often taken as supporting the fundamental role of the motor system in understanding sentences that describe actions. This effect would be related to an internal "simulation," i.e., the reactivation of past perceptual and motor experiences. However, it is not easy to establish whether this simulation predominantly involves spatial imagery or motor anticipation. In the classical ACE experiments, where a real motor response is required, the direction and motor representations are mixed. In order to disentangle spatial and motor aspects involved in the ACE, we performed six experiments in different conditions, where the motor component was always reduced, asking participants to judge the sensibility of sentences by moving a mouse, thus requiring a purely spatial representation, compatible with nonmotor interpretations. In addition, our experiments had the purpose of taking into account the possible confusion of effects of practice and of compatibility (i.e., differences in reaction times simultaneously coming from block order and opposite motion conditions). Also, in contrast to the usual paradigm, we included no-transfer filler sentences in the analysis. The ACE was not found in any experiment, a result that failed to support the idea that the ACE could be related to a simulation where spatial aspects rather than motor ones prevail. Strong practice effects were always found and were carved out from results. A surprising effect was that no-transfer sentences were processed much slower than others, perhaps revealing a sort of participants' awareness of the structure of stimuli, i.e., their finding that some of them involved motion and others did not. The relevance of these outcomes for the embodiment theory is discussed.
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Affiliation(s)
- Alberto Greco
- Department of Educational Sciences, Cognilab, Laboratory of Psychology and Cognitive Sciences, University of Genoa, Genoa, Italy
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Jun D, Johnston V, McPhail SM, O'Leary S. Are Measures of Postural Behavior Using Motion Sensors in Seated Office Workers Reliable? HUMAN FACTORS 2019; 61:1141-1161. [PMID: 30730777 DOI: 10.1177/0018720818821273] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
OBJECTIVE In this study, the reliability of measures of upper body postural behavior (head, thorax, neck, and arm) during sustained office work was evaluated. BACKGROUND Although there has been a substantial body of research examining the technical aspects of posture measurement in office workers using motion sensors, there is a paucity of literature examining whether posture-related behaviors are actually consistent among office workers in the field on different days and times. METHOD Thirty one office workers performed their usual work for three, 1-hr sessions (two morning sessions and one afternoon session) while wearing wireless motion sensors. Reliability coefficients of the derived measures of postural behavior were calculated. RESULTS Most (30/31) of the postural behavior measures demonstrated modest to excellent reliability (ICC 2.1: 0.48-0.84). Reliability appeared to be mildly affected by factors such as the time of day recordings were taken and variations in desk setups. CONCLUSION The findings suggest these measures may be a reliable method for evaluating postural behavior in the office work environment in future studies. APPLICATION Postural measurement using a technical motion sensor described an acceptable reliability to be used for risk assessment in the workplace. Consideration of assessment time and desk setting would increase the accuracy of postural measurement.
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Lee HJ, Lee SH, Seo K, Lee M, Chang WH, Choi BO, Ryu GH, Kim YH. Training for Walking Efficiency With a Wearable Hip-Assist Robot in Patients With Stroke: A Pilot Randomized Controlled Trial. Stroke 2019; 50:3545-3552. [PMID: 31623545 DOI: 10.1161/strokeaha.119.025950] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose- The purpose of this study was to investigate the effects of gait training with a newly developed wearable hip-assist robot on locomotor function and efficiency in patients with chronic stroke. Methods- Twenty-eight patients with stroke with hemiparesis were initially enrolled, and 26 patients completed the randomized controlled trial (14 in the experimental and 12 in the control groups). The experimental group participated in a gait training program over a total of 10 sessions, including 5 treadmill sessions and 5 over-ground gait training sessions while wearing a hip-assist robot, the Gait Enhancing and Motivating System (GEMS, Samsung Advanced Institute of Technology, Suwon, Republic of Korea). The control group received gait training without Gait Enhancing and Motivating System. Primary outcome measured locomotor function and cardiopulmonary metabolic energy efficiency. Also, secondary outcome measured motor function and balance parameter. Results- Compared with the control group, the experimental group had significantly greater improvement in spatiotemporal gait parameters and muscle efforts after the training intervention (P<0.05). The net cardiopulmonary metabolic energy cost (mL·kg-1·min-1) was also reduced by 14.71% in the experimental group after the intervention (P<0.01). Significant group×time interactions were observed for all parameters (P<0.05). Cardiopulmonary metabolic efficiency was strongly correlated with gait symmetry ratio in the experimental group (P<0.01). Conclusions- Gait training with Gait Enhancing and Motivating System was effective for improving locomotor function and cardiopulmonary metabolic energy efficiency during walking in patients with stroke. These findings suggest that robotic locomotor training can be adopted for rehabilitation of patients with stroke with gait disorders. Clinical Trial Registration- URL: https://clinicaltrials.gov. Unique identifier: NCT02843828.
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Affiliation(s)
- Hwang-Jae Lee
- From the Department of Physical and Rehabilitation Medicine (H.-J.L., S.-H.L., W.H.C., Y.-H.K.), Center for Prevention and Rehabilitation, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Department of Health Sciences and Technology (H.-J.L.), SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
| | - Su-Hyun Lee
- From the Department of Physical and Rehabilitation Medicine (H.-J.L., S.-H.L., W.H.C., Y.-H.K.), Center for Prevention and Rehabilitation, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Keehong Seo
- Samsung Advanced Institute of Technology, Samsung Electronics, Gyeonggi-do, Republic of Korea (K.S., M.L.)
| | - Minhyung Lee
- Samsung Advanced Institute of Technology, Samsung Electronics, Gyeonggi-do, Republic of Korea (K.S., M.L.)
| | - Won Hyuk Chang
- From the Department of Physical and Rehabilitation Medicine (H.-J.L., S.-H.L., W.H.C., Y.-H.K.), Center for Prevention and Rehabilitation, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Byung-Ok Choi
- Department of Neurology, Neuroscience Center (B.-O.C.), Center for Prevention and Rehabilitation, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Gyu-Ha Ryu
- Department of Medical Device Management and Research, SAIHST (G.-H.R.), Center for Prevention and Rehabilitation, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Yun-Hee Kim
- From the Department of Physical and Rehabilitation Medicine (H.-J.L., S.-H.L., W.H.C., Y.-H.K.), Center for Prevention and Rehabilitation, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Department of Health Sciences and Technology, Department of Medical Device Management and Research, Department of Digital Health (Y.-H.K.), SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
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García-Remeseiro T, Gutiérrez-Sánchez Á. Bibliometric analysis of the body posture in relation to visual display terminals (VDTs). Work 2019; 63:299-308. [PMID: 31156211 DOI: 10.3233/wor-192931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND In modern society, there is an increase both in the demand and the duration of computer work. Failure to correct body posture while using the computer has become a serious health hazard. OBJECTIVE To identify global trends in research related to body posture and visual display terminals (VDTs) using a bibliometric approach. METHODS In the search process, the keywords (posture *) AND (computer* OR "visual display terminal") were used in the study title section, in the Wos, Scopus and Medline databases. RESULTS 149 references published between 1970 and 2016 were analyzed. The studied variables were the years of publication, authorship and collaboration index, publication type, titles of journals, most used languages, impact of the publications, as well as content of the articles. CONCLUSIONS In recent years, the studies on body posture in relation to VDT have been increased both in quantity and quality of publications. The analysis and/or design of the workplace, as well as the elements that make up the computer (keyboard and mouse) are the most researched topics in the area.
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Affiliation(s)
- Tania García-Remeseiro
- Departamento de Didácticas Especiales, Facultad de Ciencias de la Educación y del Deporte, Instituto de Investigación Sanitaria Galicia Sur (IISGS), Universidade de Vigo, Spain
| | - Águeda Gutiérrez-Sánchez
- Departamento de Didácticas Especiales, Facultad de Ciencias de la Educación y del Deporte, Instituto de Investigación Sanitaria Galicia Sur (IISGS), Universidade de Vigo, Spain
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Coppola SM, Dixon PC, Hu B, Lin MYC, Dennerlein JT. Going Short: The Effects of Short-Travel Key Switches on Typing Performance, Typing Force, Forearm Muscle Activity, and User Experience. J Appl Biomech 2019; 35:149-156. [PMID: 30676185 PMCID: PMC7606033 DOI: 10.1123/jab.2018-0167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study examined the effects of 4 micro-travel keyboards on forearm muscle activity, typing force, typing performance, and self-reported discomfort and difficulty. A total of 20 participants completed typing tasks on 4 commercially available devices with different key switch characteristics (dome, scissors, and butterfly) and key travels (0.55, 1.3, and 1.6 mm). The device with short-travel (0.55 mm) and a dome-type key switch mechanism was associated with higher muscle activities (6%-8%, P < .01), higher typing force (12%, P < .01), slower typing speeds (8%, P < .01), and twice as much discomfort (P < .05), compared with the other 3 devices: short-travel (0.55 mm) and butterfly switch design and long travel (1.3 and 1.6 mm) with scissor key switches. Participants rated the devices with larger travels (1.3 and 1.6 mm) with least discomfort (P = .02) and difficulty (P < .01). When stratified by sex/gender, these observed associations were larger and more significant in the female participants compared with male participants. The devices with similar travel but different key switch designs had difference in outcomes and devices with different travel were sometimes not different. The results suggest that key travel alone does not predict typing force or muscle activity.
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Affiliation(s)
| | | | - Boyi Hu
- 1 Harvard T.H. Chan School of Public Health
| | | | - Jack T Dennerlein
- 1 Harvard T.H. Chan School of Public Health
- 3 Northeastern University
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Kia K, Sisley J, Johnson PW, Kim JH. Differences in typing forces, muscle activity, wrist posture, typing performance, and self-reported comfort among conventional and ultra-low travel keyboards. APPLIED ERGONOMICS 2019; 74:10-16. [PMID: 30487088 DOI: 10.1016/j.apergo.2018.07.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 07/24/2018] [Accepted: 07/27/2018] [Indexed: 06/09/2023]
Abstract
This study investigated the relative impact of ultra-low travel keyboards on typing force, muscle activity, wrist posture, typing performance, and self-reported comfort/preference as compared to a conventional keyboard. In a repeated-measures laboratory-based study, 20 subjects were invited to type for 10 min on each of five keyboards with different travel distances of 0.5, 0.7, 1.2, 1.6 (ultra-low travel keyboards), and 2.0 mm (a conventional keyboard). During the typing sessions, we measured typing force; muscle activity in extrinsic finger muscles (flexor digitorum superficialis and extensor digitorum communis), shoulder (trapezius) and neck (splenius capitis); wrist posture; typing performance; and self-reported comfort/preference. While using the ultra-low travel keyboards, subjects typed with less force and wrist extension, and had more ulnar deviation (p's < 0.0001) compared with conventional keyboard. However, these differences in typing forces were less than 0.5 N and less than 4° for both wrist extension and ulnar deviation. The general trend of data did not show any consistent or substantial differences in muscle activity (less than 2 %MVC) and typing performance (<5 WPM in speed; < 3% in accuracy), despite the observed statistical difference in the finger flexors and extensors muscle activity (p's < 0.19) and typing performance (p < 0.0001). However, the subjects preferred using conventional keyboards in most of the investigated self-reported comfort and preference criteria (p's < 0.4). In conclusion, these small differences indicate that using ultra-low travel keyboards may not have substantial differences in biomechanical exposures and typing performance compared to conventional keyboard; however, the subjective responses indicated that the ultra-low keyboards with the shortest key travel tended to be the least preferred.
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Affiliation(s)
- Kiana Kia
- School of Mechanical, Industrial, and Manufacturing Engineering, College of Engineering, Oregon State University, Corvallis, OR, United States
| | - Jonathan Sisley
- School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, United States
| | - Peter W Johnson
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, United States
| | - Jeong Ho Kim
- School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, United States.
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Huysmans MA, Eijckelhof BHW, Garza JLB, Coenen P, Blatter BM, Johnson PW, van Dieën JH, van der Beek AJ, Dennerlein JT. Predicting Forearm Physical Exposures During Computer Work Using Self-Reports, Software-Recorded Computer Usage Patterns, and Anthropometric and Workstation Measurements. Ann Work Expo Health 2018; 62:124-137. [PMID: 29186308 DOI: 10.1093/annweh/wxx092] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 10/31/2017] [Indexed: 11/14/2022] Open
Abstract
Objectives Alternative techniques to assess physical exposures, such as prediction models, could facilitate more efficient epidemiological assessments in future large cohort studies examining physical exposures in relation to work-related musculoskeletal symptoms. The aim of this study was to evaluate two types of models that predict arm-wrist-hand physical exposures (i.e. muscle activity, wrist postures and kinematics, and keyboard and mouse forces) during computer use, which only differed with respect to the candidate predicting variables; (i) a full set of predicting variables, including self-reported factors, software-recorded computer usage patterns, and worksite measurements of anthropometrics and workstation set-up (full models); and (ii) a practical set of predicting variables, only including the self-reported factors and software-recorded computer usage patterns, that are relatively easy to assess (practical models). Methods Prediction models were build using data from a field study among 117 office workers who were symptom-free at the time of measurement. Arm-wrist-hand physical exposures were measured for approximately two hours while workers performed their own computer work. Each worker's anthropometry and workstation set-up were measured by an experimenter, computer usage patterns were recorded using software and self-reported factors (including individual factors, job characteristics, computer work behaviours, psychosocial factors, workstation set-up characteristics, and leisure-time activities) were collected by an online questionnaire. We determined the predictive quality of the models in terms of R2 and root mean squared (RMS) values and exposure classification agreement to low-, medium-, and high-exposure categories (in the practical model only). Results The full models had R2 values that ranged from 0.16 to 0.80, whereas for the practical models values ranged from 0.05 to 0.43. Interquartile ranges were not that different for the two models, indicating that only for some physical exposures the full models performed better. Relative RMS errors ranged between 5% and 19% for the full models, and between 10% and 19% for the practical model. When the predicted physical exposures were classified into low, medium, and high, classification agreement ranged from 26% to 71%. Conclusion The full prediction models, based on self-reported factors, software-recorded computer usage patterns, and additional measurements of anthropometrics and workstation set-up, show a better predictive quality as compared to the practical models based on self-reported factors and recorded computer usage patterns only. However, predictive quality varied largely across different arm-wrist-hand exposure parameters. Future exploration of the relation between predicted physical exposure and symptoms is therefore only recommended for physical exposures that can be reasonably well predicted.
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Affiliation(s)
- Maaike A Huysmans
- Department of Public and Occupational Health and Amsterdam Public Health research institute, VU University Medical Center, The Netherlands.,Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, The Netherlands
| | - Belinda H W Eijckelhof
- Department of Public and Occupational Health and Amsterdam Public Health research institute, VU University Medical Center, The Netherlands.,Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, The Netherlands
| | | | - Pieter Coenen
- Department of Public and Occupational Health and Amsterdam Public Health research institute, VU University Medical Center, The Netherlands.,School of Physiotherapy and Exercise Science, Curtin University, Australia
| | - Birgitte M Blatter
- Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, The Netherlands.,Netherlands Organisation for Applied Scientific Research, TNO, The Netherlands
| | - Peter W Johnson
- Department of Environmental and Occupational Health Sciences, University of Washington, USA
| | - Jaap H van Dieën
- Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, The Netherlands.,Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, 'Vrije Universiteit' Amsterdam, Amsterdam Movement Sciences, The Netherlands
| | - Allard J van der Beek
- Department of Public and Occupational Health and Amsterdam Public Health research institute, VU University Medical Center, The Netherlands.,Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, The Netherlands
| | - Jack T Dennerlein
- Department of Public and Occupational Health and Amsterdam Public Health research institute, VU University Medical Center, The Netherlands.,Department of Environmental Health, Harvard T. H. Chan School of Public Health, USA.,Department of Physical Therapy, Movement, and Rehabilitation Sciences, Bouvé College of Health Sciences, Northeastern University, USA
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12
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Peres SC, Mehta RK, Ritchey P. Assessing ergonomic risks of software: Development of the SEAT. APPLIED ERGONOMICS 2017; 59:377-386. [PMID: 27890150 DOI: 10.1016/j.apergo.2016.09.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 08/07/2016] [Accepted: 09/27/2016] [Indexed: 06/06/2023]
Abstract
Software utilizing interaction designs that require extensive dragging or clicking of icons may increase users' risks for upper extremity cumulative trauma disorders. The purpose of this research is to develop a Self-report Ergonomic Assessment Tool (SEAT) for assessing the risks of software interaction designs and facilitate mitigation of those risks. A 28-item self-report measure was developed by combining and modifying items from existing industrial ergonomic tools. Data were collected from 166 participants after they completed four different tasks that varied by method of input (touch or keyboard and mouse) and type of task (selecting or typing). Principal component analysis found distinct factors associated with stress (i.e., demands) and strain (i.e., response). Repeated measures analyses of variance showed that participants could discriminate the different strain induced by the input methods and tasks. However, participants' ability to discriminate between the stressors associated with that strain was mixed. Further validation of the SEAT is necessary but these results indicate that the SEAT may be a viable method of assessing ergonomics risks presented by software design.
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Affiliation(s)
- S Camille Peres
- Department of Environmental and Occupational Health, Texas A&M University, College Station, TX, USA.
| | - Ranjana K Mehta
- Department of Environmental and Occupational Health, Texas A&M University, College Station, TX, USA.
| | - Paul Ritchey
- Department of Environmental and Occupational Health, Texas A&M University, College Station, TX, USA.
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Szucs KA, Molnar M. Differences in the activation and co-activation ratios of the four subdivisions of trapezius between genders following a computer typing task. Hum Mov Sci 2017; 52:181-190. [PMID: 28219842 DOI: 10.1016/j.humov.2017.02.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 01/31/2017] [Accepted: 02/02/2017] [Indexed: 12/27/2022]
Abstract
The aim of this study was to provide a description of gender differences of the activation patterns of the four subdivisions of the trapezius (clavicular, upper, middle, lower) following a 60min computer work task. Surface EMG was collected from these subdivisions from 21 healthy subjects during bilateral arm elevation pre-/post- task. Subjects completed a standardized 60min computer work task at a standard, ergonomic workstation. Normalized activation and activation ratios of each trapezius subdivision were compared between genders and condition with repeated measures ANOVAs. The interaction effect of Gender×Condition for upper trapezius% activation approached significance at p=0.051with males demonstrating greater activation post-task. The main effect of Condition was statistically significant for% activation of middle and lower trapezius (p<0.05), with both muscles demonstrating increase activation post-task. There was a statistically significant interaction effect of Gender×Condition for the Middle Trapezius/Upper Trapezius ratio and main effect of Condition for the Clavicular Trapezius/Upper Trapezius ratio, with a decreased ratio post-typing. Gender differences exist following 60min of a low force computer typing task. Imbalances in muscle activation and activation ratios following computer work may affect total shoulder kinematics and should be further explored.
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Affiliation(s)
- Kimberly A Szucs
- Department of Occupational Therapy, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282, United States.
| | - Megan Molnar
- Mahoning County Educational Service Center, 100 Debartolo Place #220, Youngstown, OH 44512, United States.
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14
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Sako S, Sugiura H, Tanoue H, Kojima M, Kono M, Inaba R. Electromyographic analysis of relevant muscle groups during completion of computer tasks using different computer mouse positions. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2016; 23:267-273. [PMID: 28002978 DOI: 10.1080/10803548.2016.1275140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND We analyzed muscular activity for different computer mouse positions during the completion of a timed computer task and determined whether the different mouse positions could affect muscular activity, productivity and perceived fatigue. METHODS The subjects were nine healthy young men. Two mouse positions were studied: the distal position (DP), with the forearm rested on the desk; the proximal position (PP), with only the wrist rested on the desk. The subjects performed a 16-min task in each position. Surface electromyography data were recorded for the upper back and shoulder muscles. Work productivity and muscular activity were measured for each mouse position. A visual analog scale was used to assess subjective fatigue. RESULTS Muscular activity was higher in muscle (m.) deltoideus (posterior) for the DP, while it was significantly higher in m. inferior infraspinatus for the PP. The visual analog scale score was significantly higher and work productivity was lower in the PP. CONCLUSIONS We found that using a mouse in the DP rather than the PP leads to less activity of the external rotators, less perceived fatigue and more productivity. This suggests that the DP is preferable to the PP for computer work involving a mouse.
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Affiliation(s)
- Shunji Sako
- a Department of Physical Therapy , Nagoya Isen Vocational College , Japan
| | - Hiromichi Sugiura
- a Department of Physical Therapy , Nagoya Isen Vocational College , Japan
| | - Hironori Tanoue
- b Department of Occupational Health , Gifu University , Japan.,c Department of Rehabilitation , Aichi Kouseiren Asuke Hospital , Japan
| | - Makoto Kojima
- d Department of Rehabilitation , Gifu Junior College of Health Science , Japan
| | - Mitsunobu Kono
- e Department of Occupational Therapy , Kinjo University , Japan
| | - Ryoichi Inaba
- b Department of Occupational Health , Gifu University , Japan
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15
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Quemelo PRV, Gasparato FDS, Vieira ER. Prevalence, risks and severity of musculoskeletal disorder symptoms among administrative employees of a Brazilian company. Work 2016; 52:533-40. [PMID: 26409374 DOI: 10.3233/wor-152131] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Musculoskeletal disorders (MSD) are common among office workers. OBJECTIVE To evaluate the prevalence, risks and symptoms of MSD among office workers of a Brazilian dairy company. METHODS Fifty office workers participated in the study. The following evaluations and questionnaires were completed: Rapid Upper Limb Assessment, Strain Index, Muscle Fatigue Assessment, Nordic General Questionnaire, and Oswestry Disability Index. RESULTS Seventy-four percent (n = 37) of the participants had MSD symptoms. The back was most commonly affected body part (81% , n = 30), followed by the upper limbs (70% , n = 26). Fifty-three percent of the workers with low back pain had mild to moderate disability, and the risk for the hands, wrists and fingers was moderate. Changes are required to reduce the risk of MSD among the participating office workers. CONCLUSION The prevalence of MSD symptoms was high; the back and upper limbs were most commonly affected. Data from the evaluations and questionnaires supplemented each other. The Rapid Upper Limb Assessment and Strain Index were better indicators of risk of MSD symptoms than the Muscle Fatigue Assessment. The participating office workers were exposed to moderate risk of developing MSD due to biomechanical overload and changes are required.
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Affiliation(s)
| | | | - Edgar Ramos Vieira
- Department of Physical Therapy, Florida International University, Miami, FL, USA
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16
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Gaudez C, Cail F. Effects of mouse slant and desktop position on muscular and postural stresses, subject preference and performance in women aged 18-40 years. ERGONOMICS 2016; 59:1473-1486. [PMID: 26847952 DOI: 10.1080/00140139.2016.1148783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This study compared muscular and postural stresses, performance and subject preference in women aged 18-40 years using a standard mouse, a vertical mouse and a slanted mouse in three different computer workstation positions. Four tasks were analysed: pointing, pointing-clicking, pointing-clicking-dragging and grasping-pointing the mouse after typing. Flexor digitorum superficialis (FDS) and extensor carpi radialis (ECR) activities were greater using the standard mouse compared to the vertical or slanted mouse. In all cases, the wrist position remained in the comfort zone recommended by standard ISO 11228-3. The vertical mouse was less comfortable and more difficult to use than the other two mice. FDS and ECR activities, shoulder abduction and wrist extension were greater when the mouse was placed next to the keyboard. Performance and subject preference were better with the unrestricted mouse positioning on the desktop. Grasping the mouse after typing was the task that caused the greatest stress. Practitioner Summary: In women, the slanted mouse and the unrestricted mouse positioning on the desktop provide a good blend of stresses, performance and preference. Unrestricted mouse positioning requires no keyboard, which is rare in practice. Placing the mouse in front of the keyboard, rather than next to it, reduced the physical load.
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Affiliation(s)
- Clarisse Gaudez
- a INRS - National Research and Safety Institute , Vandoeuvre cedex , France
| | - François Cail
- a INRS - National Research and Safety Institute , Vandoeuvre cedex , France
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17
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Kingston DC, Riddell MF, McKinnon CD, Gallagher KM, Callaghan JP. Influence of Input Hardware and Work Surface Angle on Upper Limb Posture in a Hybrid Computer Workstation. HUMAN FACTORS 2016; 58:107-119. [PMID: 26424775 DOI: 10.1177/0018720815607317] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 08/22/2015] [Indexed: 06/05/2023]
Abstract
OBJECTIVE We evaluated the effect of work surface angle and input hardware on upper-limb posture when using a hybrid computer workstation. BACKGROUND Offices use sit-stand and/or tablet workstations to increase worker mobility. These workstations may have negative effects on upper-limb joints by increasing time spent in non-neutral postures, but a hybrid standing workstation may improve working postures. METHOD Fourteen participants completed office tasks in four workstation configurations: a horizontal or sloped 15° working surface with computer or tablet hardware. Three-dimensional right upper-limb postures were recorded during three tasks: reading, form filling, and writing e-mails. Amplitude probability distribution functions determined the median and range of upper-limb postures. RESULTS The sloped-surface tablet workstation decreased wrist ulnar deviation by 5° when compared to the horizontal-surface computer when reading. When using computer input devices (keyboard and mouse), the shoulder, elbow, and wrist were closest to neutral joint postures when working on a horizontal work surface. The elbow was 23° and 15° more extended, whereas the wrist was 6° less ulnar deviated, when reading compared to typing forms or e-mails. CONCLUSION We recommend that the horizontal-surface computer configuration be used for typing and the sloped-surface tablet configuration be used for intermittent reading tasks in this hybrid workstation. APPLICATION Offices with mobile employees could use this workstation for alternating their upper-extremity postures; however, other aspects of the device need further investigation.
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18
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Heiden M, Mathiassen SE, Garza J, Liv P, Wahlström J. A Comparison of Two Strategies for Building an Exposure Prediction Model. ANNALS OF OCCUPATIONAL HYGIENE 2015; 60:74-89. [PMID: 26424806 DOI: 10.1093/annhyg/mev072] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 08/09/2015] [Indexed: 12/30/2022]
Abstract
Cost-efficient assessments of job exposures in large populations may be obtained from models in which 'true' exposures assessed by expensive measurement methods are estimated from easily accessible and cheap predictors. Typically, the models are built on the basis of a validation study comprising 'true' exposure data as well as an extensive collection of candidate predictors from questionnaires or company data, which cannot all be included in the models due to restrictions in the degrees of freedom available for modeling. In these situations, predictors need to be selected using procedures that can identify the best possible subset of predictors among the candidates. The present study compares two strategies for selecting a set of predictor variables. One strategy relies on stepwise hypothesis testing of associations between predictors and exposure, while the other uses cluster analysis to reduce the number of predictors without relying on empirical information about the measured exposure. Both strategies were applied to the same dataset on biomechanical exposure and candidate predictors among computer users, and they were compared in terms of identified predictors of exposure as well as the resulting model fit using bootstrapped resamples of the original data. The identified predictors were, to a large part, different between the two strategies, and the initial model fit was better for the stepwise testing strategy than for the clustering approach. Internal validation of the models using bootstrap resampling with fixed predictors revealed an equally reduced model fit in resampled datasets for both strategies. However, when predictor selection was incorporated in the validation procedure for the stepwise testing strategy, the model fit was reduced to the extent that both strategies showed similar model fit. Thus, the two strategies would both be expected to perform poorly with respect to predicting biomechanical exposure in other samples of computer users.
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Affiliation(s)
- Marina Heiden
- 1.Centre for Musculoskeletal Research, Department of Occupational and Public Health Sciences, University of Gävle, 801 76 Gävle, Sweden;
| | - Svend Erik Mathiassen
- 1.Centre for Musculoskeletal Research, Department of Occupational and Public Health Sciences, University of Gävle, 801 76 Gävle, Sweden
| | - Jennifer Garza
- 1.Centre for Musculoskeletal Research, Department of Occupational and Public Health Sciences, University of Gävle, 801 76 Gävle, Sweden; 2.Division of Occupational and Environmental Medicine, UConn Health, Farmington, CT 06030, USA
| | - Per Liv
- 1.Centre for Musculoskeletal Research, Department of Occupational and Public Health Sciences, University of Gävle, 801 76 Gävle, Sweden; 3.Centre for Research and Development, Uppsala University/County Council of Gävleborg, 801 88 Gävle, Sweden
| | - Jens Wahlström
- 4.Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine, Umeå University, 901 87 Umeå, Sweden
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Hallman DM, Srinivasan D, Mathiassen SE. Short- and long-term reliability of heart rate variability indices during repetitive low-force work. Eur J Appl Physiol 2014; 115:803-12. [DOI: 10.1007/s00421-014-3066-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 11/25/2014] [Indexed: 12/31/2022]
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20
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Eijckelhof BHW, Huysmans MA, Blatter BM, Leider PC, Johnson PW, van Dieën JH, Dennerlein JT, van der Beek AJ. Office workers' computer use patterns are associated with workplace stressors. APPLIED ERGONOMICS 2014; 45:1660-1667. [PMID: 25005311 DOI: 10.1016/j.apergo.2014.05.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 04/09/2014] [Accepted: 05/26/2014] [Indexed: 06/03/2023]
Abstract
This field study examined associations between workplace stressors and office workers' computer use patterns. We collected keyboard and mouse activities of 93 office workers (68F, 25M) for approximately two work weeks. Linear regression analyses examined the associations between self-reported effort, reward, overcommitment, and perceived stress and software-recorded computer use duration, number of short and long computer breaks, and pace of input device usage. Daily duration of computer use was, on average, 30 min longer for workers with high compared to low levels of overcommitment and perceived stress. The number of short computer breaks (30 s-5 min long) was approximately 20% lower for those with high compared to low effort and for those with low compared to high reward. These outcomes support the hypothesis that office workers' computer use patterns vary across individuals with different levels of workplace stressors.
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Affiliation(s)
- Belinda H W Eijckelhof
- Department of Public and Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands; Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, PO Box 7057, 1007 MB Amsterdam, The Netherlands
| | - Maaike A Huysmans
- Department of Public and Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands; Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
| | - Birgitte M Blatter
- Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, PO Box 7057, 1007 MB Amsterdam, The Netherlands; Netherlands Organization for Applied Scientific Research, TNO, Postbus 718, 2130 AS Hoofddorp, The Netherlands
| | - Priscilla C Leider
- Department of Public and Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands
| | - Peter W Johnson
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Box 357234, Seattle, USA
| | - Jaap H van Dieën
- Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, PO Box 7057, 1007 MB Amsterdam, The Netherlands; MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorststraat 9, 1081 BT Amsterdam, The Netherlands
| | - Jack T Dennerlein
- Department of Public and Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands; Department of Environmental Health, Harvard School of Public Health, 665 Huntington Avenue, Boston, USA; Department of Physical Therapy, Bouvé College of Health Sciences, Northeastern University, 360 Huntington Avenue, Boston, USA
| | - Allard J van der Beek
- Department of Public and Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands; Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
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21
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Barbieri DF, Srinivasan D, Mathiassen SE, Nogueira HC, Oliveira AB. The ability of non-computer tasks to increase biomechanical exposure variability in computer-intensive office work. ERGONOMICS 2014; 58:50-64. [PMID: 25345757 DOI: 10.1080/00140139.2014.965753] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Postures and muscle activity in the upper body were recorded from 50 academics office workers during 2 hours of normal work, categorised by observation into computer work (CW) and three non-computer (NC) tasks (NC seated work, NC standing/walking work and breaks). NC tasks differed significantly in exposures from CW, with standing/walking NC tasks representing the largest contrasts for most of the exposure variables. For the majority of workers, exposure variability was larger in their present job than in CW alone, as measured by the job variance ratio (JVR), i.e. the ratio between min-min variabilities in the job and in CW. Calculations of JVRs for simulated jobs containing different proportions of CW showed that variability could, indeed, be increased by redistributing available tasks, but that substantial increases could only be achieved by introducing more vigorous tasks in the job, in casu illustrated by cleaning.
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Affiliation(s)
- Dechristian França Barbieri
- a Laboratory of Clinical and Occupational Kinesiology (LACO), Department of Physical Therapy , Federal University of São Carlos , Washington Luiz Road, km 235, SP310, 13565-905 São Carlos , Brazil
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22
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Bruno Garza JL, Eijckelhof BHW, Huysmans MA, Johnson PW, van Dieen JH, Catalano PJ, Katz JN, van der Beek AJ, Dennerlein JT. Prediction of trapezius muscle activity and shoulder, head, neck, and torso postures during computer use: results of a field study. BMC Musculoskelet Disord 2014; 15:292. [PMID: 25186007 PMCID: PMC4161866 DOI: 10.1186/1471-2474-15-292] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 08/27/2014] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Due to difficulties in performing direct measurements as an exposure assessment technique, evidence supporting an association between physical exposures such as neck and shoulder muscle activities and postures and musculoskeletal disorders during computer use is limited. Alternative exposure assessment techniques are needed. METHODS We predicted the median and range of amplitude (90th-10th percentiles) of trapezius muscle activity and the median and range of motion (90th-10th percentiles) of shoulder, head, neck, and torso postures based on two sets of parameters: the distribution of keyboard/mouse/idle activities only ("task-based" predictions), and a comprehensive set of task, questionnaire, workstation, and anthropometric parameters ("expanded model" predictions). We compared the task-based and expanded model predictions based on R2 values, root mean squared (RMS) errors, and relative RMS errors calculated compared to direct measurements. RESULTS The expanded model predictions of the median and range of amplitude of trapezius muscle activity had consistently better R2 values (range 0.40-0.55 compared to 0.00-0.06), RMS errors (range 2-3%MVC compared to 3-4%MVC), and relative RMS errors (range 10-14%MVC compared to 16-19%MVC) than the task-based predictions. The expanded model predictions of the median and range of amplitude of postures also had consistently better R2 values (range 0.22-0.58 compared to 0.00-0.35), RMS errors (range 2-14 degrees compared to 3-22 degrees), and relative RMS errors (range 9-21 degrees compared to 13-42 degrees) than the task-based predictions. CONCLUSIONS The variation in physical exposures across users performing the same task is large, especially in comparison to the variation across tasks. Thus, expanded model predictions of physical exposures during computer use should be used rather than task-based predictions to improve exposure assessment for future epidemiological studies. Clinically, this finding also indicates that computer users will have differences in their physical exposures even when performing the same tasks.
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Affiliation(s)
- Jennifer L Bruno Garza
- />Department of Environmental Health, Harvard University, Boston, USA
- />Division of Occupational and Environmental Medicine, UConn Health, Farmington, USA
| | - Belinda HW Eijckelhof
- />Department of Public and Occupational Health VU University Medical Center, Amsterdam, The Netherlands
- />EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- />Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, Amsterdam, The Netherlands
| | - Maaike A Huysmans
- />Department of Public and Occupational Health VU University Medical Center, Amsterdam, The Netherlands
- />EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- />Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, Amsterdam, The Netherlands
| | - Peter W Johnson
- />Department of Environmental Health, University of Washington Seattle, Seattle, USA
| | - Jaap H van Dieen
- />Faculty of Human Movement Sciences, VU University, Amsterdam, The Netherlands
| | - Paul J Catalano
- />Department of Biostatistics, Harvard School of Public Health Boston, Boston, USA
- />Dana Farber Cancer Institute Boston, Boston, USA
| | - Jeffrey N Katz
- />Department of Environmental Health, Harvard University, Boston, USA
- />Department of Epidemiology, Harvard School of Public Health, Boston, USA
- />Division of Rheumatology, Immunology and Allergy, Brigham and Women’s Hospital, Boston, USA
- />Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, USA
| | - Allard J van der Beek
- />Department of Public and Occupational Health VU University Medical Center, Amsterdam, The Netherlands
- />EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- />Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, Amsterdam, The Netherlands
| | - Jack T Dennerlein
- />Department of Environmental Health, Harvard University, Boston, USA
- />EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- />Department of Physical Therapy, Bouvé College of Health Sciences, Northeastern University, Boston, USA
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Ciccarelli M, Straker L, Mathiassen SE, Pollock C. Posture variation among office workers when using different information and communication technologies at work and away from work. ERGONOMICS 2014; 57:1678-1686. [PMID: 25116058 DOI: 10.1080/00140139.2014.945493] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Office workers perform tasks using different information and communication technologies (ICT) involving various postures. Adequate variation in postures and muscle activity is generally believed to protect against musculoskeletal complaints, but insufficient information exists regarding the effect on postural variation of using different ICT. Thus, this study among office workers aimed to determine and compare postures and postural variation associated with using distinct types of ICT. Upper arm, head and trunk postures of 24 office workers were measured with the Physiometer over a whole day in their natural work and away-from-work environments. Postural variation was quantified using two indices: APDF(90-10) and EVA(sd). Various ICT had different postural means and variation. Paper-based tasks had more non-neutral, yet also more variable postures. Electronics-based tasks had more neutral postures, with less postural variability. Tasks simultaneously using paper- and electronics-based ICT had least neutral and least variable postures. Tasks without ICT usually had the most posture variability. Interspersing tasks involving different ICT could increase overall exposure variation among office workers and may thus contribute to musculoskeletal risk reduction.
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Affiliation(s)
- Marina Ciccarelli
- a School of Occupational Therapy & Social Work , Curtin University , Perth , Australia
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24
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Onyebeke LC, Young JG, Trudeau MB, Dennerlein JT. Effects of forearm and palm supports on the upper extremity during computer mouse use. APPLIED ERGONOMICS 2014; 45:564-570. [PMID: 24054504 DOI: 10.1016/j.apergo.2013.07.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 07/20/2013] [Accepted: 07/30/2013] [Indexed: 06/02/2023]
Abstract
The use of forearm and palm supports has been associated with lower neck and shoulder muscle activity as well as reduced musculoskeletal discomfort during keyboard use, however, few studies have investigated their effect during computer mouse use. Eight men and eight women completed several computer mousing tasks in six arm support conditions: Forearm Support, Flat Palm Support, Raised Palm Support, Forearm + Flat Palm Support, Forearm + Raised Palm Support, and No Support. Concurrently, an infrared three-dimensional motion analysis system measured postures, six-degree-of-freedom force-torque sensors measured applied forces & torques, and surface electromyography measured muscle activity. The use of forearm support compared to the no support condition was significantly associated with less shoulder muscle activity & torque, and the raised palm support was associated with less wrist extension. Forearm supports reduced shoulder flexion torque by 90% compared to no support. The use of either support also resulted in lower applied forces to the mouse pad. Participants reported less musculoskeletal discomfort when using a support. These results provide recommendations for office workstation setup and inform ergonomists of effective ways to reduce musculoskeletal exposures.
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Affiliation(s)
- Lynn C Onyebeke
- Department of Environmental Health, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA
| | - Justin G Young
- Kettering University, 1700 University Ave., Flint, MI 48504, USA
| | - Matthieu B Trudeau
- Department of Environmental Health, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA
| | - Jack T Dennerlein
- Department of Environmental Health, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA; Department of Physical Therapy, Bouvé College of Health Sciences, Northeastern University, 6 Robinson Hall, 360 Huntington Ave., Boston, MA 02115, USA.
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25
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Mainenti MRM, Felicio LR, Rodrigues ÉDC, Ribeiro da Silva DT, Vigário dos Santos P. Pain, Work-related Characteristics, and Psychosocial Factors among Computer Workers at a University Center. J Phys Ther Sci 2014; 26:567-73. [PMID: 24764635 PMCID: PMC3996423 DOI: 10.1589/jpts.26.567] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 11/04/2013] [Indexed: 11/24/2022] Open
Abstract
[Purpose] Complaint of pain is common in computer workers, encouraging the investigation of pain-related workplace factors. This study investigated the relationship among work-related characteristics, psychosocial factors, and pain among computer workers from a university center. [Subjects and Methods] Fifteen subjects (median age, 32.0 years; interquartile range, 26.8-34.5 years) were subjected to measurement of bioelectrical impedance; photogrammetry; workplace measurements; and pain complaint, quality of life, and motivation questionnaires. [Results] The low back was the most prevalent region of complaint (76.9%). The number of body regions for which subjects complained of pain was greater in the no rest breaks group, which also presented higher prevalences of neck (62.5%) and low back (100%) pain. There were also observed associations between neck complaint and quality of life; neck complaint and head protrusion; wrist complaint and shoulder angle; and use of a chair back and thoracic pain. [Conclusion] Complaint of pain was associated with no short rest breaks, no use of a chair back, poor quality of life, high head protrusion, and shoulder angle while using the mouse of a computer.
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Affiliation(s)
| | - Lilian Ramiro Felicio
- Augusto Motta University Center (UNISUAM): Praça das
Nações, 34, 3rd floor, Bonsucesso, Rio de Janeiro, Brazil
| | - Érika de Carvalho Rodrigues
- Augusto Motta University Center (UNISUAM): Praça das
Nações, 34, 3rd floor, Bonsucesso, Rio de Janeiro, Brazil
| | | | - Patrícia Vigário dos Santos
- Augusto Motta University Center (UNISUAM): Praça das
Nações, 34, 3rd floor, Bonsucesso, Rio de Janeiro, Brazil
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26
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Qin J, Chen H, Dennerlein JT. Wrist posture affects hand and forearm muscle stress during tapping. APPLIED ERGONOMICS 2013; 44:969-976. [PMID: 23591089 DOI: 10.1016/j.apergo.2013.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 03/05/2013] [Accepted: 03/07/2013] [Indexed: 06/02/2023]
Abstract
Non-neutral wrist posture is a risk factor of the musculoskeletal disorders among computer users. This study aimed to assess internal loads on hand and forearm musculature while tapping in different wrist postures. Ten healthy subjects tapped on a key switch using their index finger in four wrist postures: straight, ulnar deviated, flexed and extended. Torque at the finger and wrist joints were calculated from measured joint postures and fingertip force. Muscle stresses of the six finger muscles and four wrist muscles that balanced the calculated joint torques were estimated using a musculoskeletal model and optimization algorithm minimizing the squared sum of muscle stress. Non-neutral wrist postures resulted in greater muscle stresses than the neutral (straight) wrist posture, and the stress in the extensor muscles were greater than the flexors in all conditions. Wrist extensors stress remained higher than 4.5 N/cm² and wrist flexor stress remained below 0.5 N/cm² during tapping. The sustained high motor unit recruitment of extensors suggests a greater risk than other muscles especially in flexed wrist posture. This study demonstrated from the perspective of internal tissue loading the importance of maintaining neutral wrist posture during keying activities.
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Affiliation(s)
- Jin Qin
- Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115, USA
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27
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Dasog M, Koirala K, Liu P, Clancy EA. Electromyogram bandwidth requirements when the signal is whitened. IEEE Trans Neural Syst Rehabil Eng 2013; 22:664-70. [PMID: 24122574 DOI: 10.1109/tnsre.2013.2283403] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Whitening the surface electromyogram (EMG) improves EMG amplitude (EMGσ) and EMG-torque estimation. Laboratory studies utilizing contraction levels up to maximum voluntary contraction (MVC) show that whitening is useful over a frequency band extending to 1000-2000 Hz. However, EMG electrode systems with such wide bandwidth are uncommon, particularly in real-time applications; and these contraction levels are also not common. Thus, we studied the influence of the frequency band over which whitening was performed versus the resulting performance. Low-level, torque-varying contractions (average torque level of 18.5% flexion MVC) of the elbow were contrasted with medium-level 50% MVC constant-torque contractions. For each, the maximum whitening bandwidth was varied between 30-2000 Hz. The low-level contractions (which incorporate the contraction range of most daily tasks) showed that performance utilizing frequencies out to 400-500 Hz was not statistically different than results out to the full available frequency (2000 Hz). For the medium-level (50% MVC) contractions, frequencies out to 800-900 Hz were statistically equivalent to the full bandwidth. These results suggest that conventional electrodes with a typical passband of ∼ 500 Hz are appropriate when whitening data from contraction levels typically experienced in many applications. Wider bandwidths may be advantageous for strenuous activities.
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28
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Bruno Garza JL, Eijckelhof BH, Huysmans MA, Catalano PJ, Katz JN, Johnson PW, van Dieen JH, van der Beek AJ, Dennerlein JT. The effect of over-commitment and reward on trapezius muscle activity and shoulder, head, neck, and torso postures during computer use in the field. Am J Ind Med 2013; 56:1190-200. [PMID: 23818000 PMCID: PMC4522287 DOI: 10.1002/ajim.22192] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2013] [Indexed: 11/09/2022]
Abstract
BACKGROUND Because of reported associations of psychosocial factors and computer related musculoskeletal symptoms, we investigated the effects of a workplace psychosocial factor, reward, in the presence of over-commitment, on trapezius muscle activity and shoulder, head, neck, and torso postures during computer use. METHODS We measured 120 office workers across four groups (lowest/highest reward/over-commitment), performing their own computer work at their own workstations over a 2-hr period. RESULTS Median trapezius muscle activity (P = 0.04) and median neck flexion (P = 0.03) were largest for participants reporting simultaneously low reward and high over-commitment. No differences were observed for other muscle activities or postures. CONCLUSIONS These data suggest that the interaction of reward and over-commitment can affect upper extremity muscle activity and postures during computer use in the real work environment. This finding aligns with the hypothesized biomechanical pathway connecting workplace psychosocial factors and musculoskeletal symptoms of the neck and shoulder.
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Affiliation(s)
| | - Belinda H.W. Eijckelhof
- Department of Public and Occupational Health, VU University Medical Center, Amsterdam, The Netherlands
- EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, Amsterdam, The Netherlands
| | - Maaike A. Huysmans
- Department of Public and Occupational Health, VU University Medical Center, Amsterdam, The Netherlands
- EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, Amsterdam, The Netherlands
| | - Paul J. Catalano
- Department of Biostatistics, Harvard School of Public Health, Boston, U.S.A
- Dana Farber Cancer Institute, Boston, U.S.A
| | - Jeffrey N. Katz
- Department of Environmental Health, Harvard University, Boston, U.S.A
- Department of Epidemiology, Harvard School of Public Health, Boston, U.S.A
- Division of Rheumatology, Immunology and Allergy, Brigham and Women’s Hospital, Boston, U.S.A
- Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, U.S.A
| | - Peter W. Johnson
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, U.S.A
| | - Jaap H. van Dieen
- EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- Research institute MOVE, Faculty of Human Movement Sciences, VU University Amsterdam, Amsterdam, the Netherlands
| | - Allard J. van der Beek
- Department of Public and Occupational Health, VU University Medical Center, Amsterdam, The Netherlands
- EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- Body@Work Research Center on Physical Activity, Work and Health, TNO-VU/VUmc, Amsterdam, The Netherlands
| | - Jack T. Dennerlein
- Department of Environmental Health, Harvard University, Boston, U.S.A
- EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- Department of Physical Therapy, Northeastern University, Boston, U.S.A
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Quemelo PRV, Vieira ER. Biomechanics and performance when using a standard and a vertical computer mouse. ERGONOMICS 2013; 56:1336-1344. [PMID: 23777482 DOI: 10.1080/00140139.2013.805251] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
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.
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Affiliation(s)
- Paulo R V Quemelo
- a Department of Physical Therapy , University of Franca , Franca , Brazil
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Levanon Y, Gefen A, Lerman Y, Givon U, Ratzon NZ. Reducing musculoskeletal disorders among computer operators: comparison between ergonomics interventions at the workplace. ERGONOMICS 2012; 55:1571-1585. [PMID: 23039764 DOI: 10.1080/00140139.2012.726654] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
UNLABELLED Typing is associated with musculoskeletal disorders (MSDs) caused by multiple risk factors. This control study aimed to evaluate the efficacy of a workplace intervention for reducing MSDs among computer workers. Sixty-six subjects with and without MSD were assigned consecutively to one of three groups: ergonomics intervention (work site and body posture adjustments, muscle activity training and exercises) accompanied with biofeedback training, the same ergonomics intervention without biofeedback and a control group. Evaluation of MSDs, body posture, psychosocial status, upper extremity (UE) kinematics and muscle surface electromyography were carried out before and after the intervention in the workplace and the motion lab. Our main hypothesis that significant differences in the reduction of MSDs will exist between subjects in the study groups and controls was confirmed (χ(2) = 13.3; p = 0.001). Significant changes were found in UE kinematics and posture as well. Both ergonomics interventions effectively reduced MSD and improved body posture. PRACTITIONER SUMMARY This study aimed to test the efficacy of an individual workplace intervention programme among computer workers by evaluating musculoskeletal disorders (MSDs), body posture, upper extremity kinematics, muscle activity and psychosocial factors were tested. The proposed ergonomics interventions effectively reduced MSDs and improved body posture.
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Affiliation(s)
- Yafa Levanon
- Department of Occupational Therapy, School of Health Professions, Tel Aviv University, P.O.B. 39040, Tel Aviv, 69978 Israel.
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31
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Huang TS, Cheng WC, Lin JJ. Relationship between trapezius muscle activity and typing speed: taping effect. ERGONOMICS 2012; 55:1404-1411. [PMID: 22897702 DOI: 10.1080/00140139.2012.709543] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Clinically, over-activation of upper trapezius (UT) muscular activity is a common cause of symptoms in computer users. The purpose of this study was to investigate the correlation between trapezius muscular activity and typing speed with and without taping. Twelve participants performed a typing task for 15 min with and without taping on the UT muscle. Electromyography (EMG) of the muscular activity of UT and lower trapezius (LT) was recorded. With or without taping, there was a significantly positive correlation (r = 0.40, p = 0.04) between typing speed and UT/LT. Additionally, UT and UT/LT ratios were lower with taping than without taping (difference = 5.2% and 26.9%). The LT ratio was higher with taping than without taping (difference = 5.8%). Taping can alter the muscular activity of the trapezius during typing and may have the potential to be applied in computer users to prevent over-activation of UT muscular activity. Practitioner Summary: The effect of taping was tested on typing speed and trapezius muscular activity. With or without taping, typing speed was correlated with trapezius activity. The muscle activity of the trapezius, however, was lower with taping than without taping. Thus, taping has the potential to prevent over-activation of UT muscular activity during typing.
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Affiliation(s)
- Tsun-Shun Huang
- School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
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32
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Bruno-Garza JL, Catalano PJ, Katz JN, Huysmans MA, Dennerlein JT. Developing a framework for predicting upper extremity muscle activities, postures, velocities, and accelerations during computer use: the effect of keyboard use, mouse use, and individual factors on physical exposures. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2012; 9:691-698. [PMID: 23066993 PMCID: PMC3486439 DOI: 10.1080/15459624.2012.728927] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Prediction models were developed based on keyboard and mouse use in combination with individual factors that could be used to predict median upper extremity muscle activities, postures, velocities, and accelerations experienced during computer use. In the laboratory, 25 participants performed five simulated computer trials with different amounts of keyboard and mouse use ranging from a highly keyboard-intensive trial to a highly mouse-intensive trial. During each trial, muscle activity and postures of the shoulder and wrist and velocities and accelerations of the wrists, along with percentage keyboard and mouse use, were measured. Four individual factors (hand length, shoulder width, age, and gender) were also measured on the day of data collection. Percentage keyboard and mouse use explained a large amount of the variability in wrist velocities and accelerations. Although hand length, shoulder width, and age were each significant predictors of at least one median muscle activity, posture, velocity, or acceleration exposure, these individual factors explained very little variability in addition to percentage keyboard and mouse use in any of the physical exposures investigated. The amounts of variability explained for models predicting median wrist velocities and accelerations ranged from 75 to 84% but were much lower for median muscle activities and postures (0-50%). RMS errors ranged between 8 to 13% of the range observed. While the predictions for wrist velocities and accelerations may be able to be used to improve exposure assessment for future epidemiologic studies, more research is needed to identify other factors that may improve the predictions for muscle activities and postures.
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Affiliation(s)
| | - Paul J. Catalano
- Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts
- Dana Farber Cancer Institute, Boston, Massachusetts
| | - Jeffrey N. Katz
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
- Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts
- Division of Rheumatology, Immunology and Allergy, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
- Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Maaike A. Huysmans
- Department of Public and Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
- BodyatWork, Research Center on Physical Activity, Work and Health, TNO-VU/Vumc, The Netherlands
| | - Jack T. Dennerlein
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
- Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
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