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Abstract

Using traditional back tables (BT) in operating rooms (OR) can lead to high physical/cognitive demand on nurses due to repetitive manual material handling activities. A multi-tier table (MTT) has been developed to relieve such stressors by providing extra working surfaces to avoid stacking the instrument trays and facilitate access to surgical tools. In this study, sixteen participants performed lifting/lowering and instrument findings tasks on each table, where kinematics, kinetics, subjective, and performance-related measures were recorded. Results indicated that MTT required lesser shoulder flexion (p-value<0.001), ~14% lower shoulder loads (0.012), task completion time (<0.001), and cognitive/physical workloads (<0.004). Although peak low-back demands were ~15% higher using MTT, the number of lifts to complete the same task was 60% lower, leading to lower cumulative demand on the low-back musculature. Utilizing MTT in OR could reduce demand and increase nurses' efficiency, leading to reduced risk of WMSDs and the total time of surgery.

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... Performing comprehensive laboratory assessments can provide valuable insights into the advantages/limitations of an intervention (in terms of physical/cognitive demands imposed on an individual), thereby assisting in its development and effective implementation [11], [12]. Studies that evaluated BSEs in trunk bending tasks considered forward bending but focused on static holding for a short period or until fatigue [13]- [15]. ...
Conference Paper
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Assalamualaikum and Salam Sejahtera all . My latest book in Amazon. . Musculoskeletal Disorders: Industrial Insights and Ergonomic Interventions: Guidelines for Postgraduates and Researchers For those who wanted to pursue Masters and PhD in Ergonomics research, you can download this ebook for free until 13 September 2023 via kindle unlimited. International: USA : https://a.co/d/ahPetvX United kingdom : https://amzn.eu/d/a5sApiI Australia : https://amzn.eu/d/a5sApiI Canada: https://amzn.eu/d/a5sApiI India : https://amzn.eu/d/5tA2ojy And for those who wanted to learn Quranic words, you can download Think Quran apps via this link. https://app.thinkquran.com?r=drhumaizi_unimap&act=ob
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For those who wanted to pursue Masters and PhD in Material Handlings in Ergonomics research, you can download this ebook for free until 29 July 2023 via kindle unlimited. International: USA : https://a.co/d/9HHelBi United kingdom : https://amzn.eu/d/7pnIghl Australia : https://amzn.eu/d/7pnIghl Canada: https://amzn.eu/d/7pnIghl India : https://amzn.eu/d/7pnIghl And for those who wanted to learn Quranic words, you can download Think Quran apps via this link. https://app.thinkquran.com?r=drhumaizi_unimap&act=ob The modern world of work is fraught with physical demands, presenting both opportunities and challenges that pertain to the well-being of workers across a multitude of industries. This book, "Ergonomic Risk Evaluation and Reduction in Material Handling", is an endeavor to encapsulate the exhaustive research, comprehensive strategies, and revolutionary methodologies currently in play to navigate these challenges. More importantly, it outlines the path forward for a future where safe, productive manual labor is not just a possibility, but a reality. In an age where workers grapple with physical strain, the necessity of ergonomics has become all the more salient. Whether it's in agriculture, construction, healthcare, or the textile industry, musculoskeletal disorders (MSDs) pose a significant threat to the health and productivity of workers. In response, a robust body of research has emerged, using methodologies and tools like the Rapid Entire Body Assessment (REBA), Ergonomic Checkpoints tool, Rodgers muscle fatigue analysis, and RULA to understand and mitigate these risks. The initial chapters delve into a comprehensive introduction to the realm of ergonomics, covering the breadth and depth of studies that have focused on manual labor, the ergonomic risks inherent in it, and the interventions or adaptations proposed to reduce these risks. We explore how the landscape of ergonomic evaluation has been shaped by the pioneering work of several researchers across various industries, showcasing how these diverse sectors have seen improvements through innovative solutions, design, and workspace reconfigurations. Our exploration into methodologies forms the bedrock of this book, underscoring how numerous tools and technologies have been employed to garner a comprehensive understanding of MSDs, enhance work postures, and gauge the impacts of diverse tasks on muscular workload. From REBA to Rodgers muscle fatigue analysis, every tool and technique is analyzed, their contributions towards risk reduction in various sectors illuminated. Finally, the book offers a vision of the future. We explore what lies ahead in ergonomic risk evaluation and reduction, examining potential areas of study such as ergonomic interventions, design evaluations, comparative and longitudinal studies, the application of technology in ergonomics, and industry-specific investigations in manual material handling. These topics, descriptions, and objectives provide a roadmap for researchers and practitioners to build upon existing knowledge, inviting further investigation and innovation in the field of ergonomics. "Ergonomic Risk Evaluation and Reduction in Material Handling" serves as a comprehensive resource for researchers, practitioners, and anyone interested in the realm of ergonomics. With its focus on evaluating and reducing ergonomic risks in material handling tasks across a multitude of industries, this book hopes to contribute to a future where work-related musculoskeletal disorders are significantly minimized, productivity is enhanced, and workers can function in an environment that is both safe and conducive to their health and well-being. As you navigate these pages, we hope you find the insights enlightening and the foresight inspiring.
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Localized muscle fatigue (LMF) during a repetitive task can be influenced by several aspects such as the level and duration of exertions. Among these aspects, though, the influence of cycle time remains unclear. Here, the effect of cycle time on LMF and performance was examined for a simple biomechanical system during repetitive static efforts. Participants performed 1-hour trials of intermittent isometric index finger abduction with a duty cycle of 50% in all combinations of two cycle times (30 and 60 sec) and two exertion levels (15 and 25% of maximum voluntary capacity). Measures of discomfort, performance (force fluctuations), and muscle capacity (voluntary strength and low-frequency twitch responses) were obtained, all of which demonstrated a beneficial effect of the 30 sec cycle time. Specifically, the shorter cycle time led to lower rates of increase in perceived discomfort, lower rates of increase in force fluctuations, lower rates of decrease in voluntary capacity, and smaller changes in twitch responses. These benefits, reflecting less LMF development in the shorter cycle time, were quite consistent between genders and the two levels of effort. Results of this study can be used to modify current models predicting work-rest allowance and/or LMF, helping to enhance performance and reduce the risk of adverse musculoskeletal outcomes.
Article
Background: Musculoskeletal disorders are one of the most common work-related diseases. Frequently this association is thought to have a temporal cause-effect relation. The absence of accessible diagnostic criteria and ethological cause-effect demonstration are probably important reasons for the lack of good evidence data on these pathologies. Objective: For these reasons, the authors aim to present a systematic review on prevalence and incidence of the upper limb WRMSD. Methods: The survey was conducted for papers published between January 1st, 2000 and July 2012, according to the PRISMA statement (2009) guidelines. Results: From the 2016 papers obtained, 94 met the qualitative selection criteria. From these 27 address upper-limb WRMSD, and 17 present data on prevalence or incidence on upper-limb musculoskeletal diseases, six of them with a control group. Annual incidence ranges from 0.08 to 6.3, and prevalence from 0.14 to 14.9. Rotator cuff syndrome among shoe industry workers, present the highest incidence, and cubital, radial or ulnar nerve entrapment, the highest prevalence among a miscellaneous group of workers. Conclusions: More studies are needed to clarify the relation between work and WRMSD's, especially prospective investigations from different economic sectors and work activities, but with similar, reproducible and comparable methodologies.
Article
The aims of this study were to investigate the stationarity of trunk muscle electromyography (EMG) signals at various loads, flexion, twisting and sampling window sizes and to determine the post-processing conditions that improve the quality of frequency analysis in measuring muscle fatigue. Eight healthy individuals participated in the experiment, and the erector spinae muscle was used to collect the signals. All participants performed sustained isometric contractions at various combinations of three loads (0, 25 and 50% MVC), three flexion angles (0, 22.5 and 45°) and five twisting angles (−30, −15, 0, 15, and 30°). The signal collected for 20 s in each experimental task was analyzed using the five window sizes (250, 500, 750, 1000, and 2000 ms). The stationarity of the signal was examined using reverse and modified reverse arrangements tests. We determined the stationary level of the signal to be significantly affected by the window size. It was found that a window size of 750 ms was the optimal window size of the five considered in this study. Relevance to industry This study focuses on suggesting an operative method to precisely measure the muscle fatigue in a lifting task. The results of this study will help researchers evaluate the risk of low back pain caused by local muscle fatigue measured by electromyography (EMG).
Conference Paper
NASA-TLX is a multi-dimensional scale designed to obtain workload estimates from one or more operators while they are performing a task or immediately afterwards. The years of research that preceded subscale selection and the weighted averaging approach resulted in a tool that has proven to be reasonably easy to use and reliably sensitive to experimentally important manipulations over the past 20 years. Its use has spread far beyond its original application (aviation), focus (crew complement), and language (English). This survey of 550 studies in which NASA-TLX was used or reviewed was undertaken to provide a resource for a new generation of users. The goal was to summarize the environments in which it has been applied, the types of activities the raters performed, other variables that were measured that did (or did not) covary, methodological issues, and lessons learned
Article
Increased workload during task performance may increase fatigue and facilitate errors. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a previously validated tool for workload self-assessment. We assessed the relationship of workload and performance during simulator training on a complex laparoscopic task. NASA-TLX workload data from three separate trials were analyzed. All participants were novices (n = 28), followed the same curriculum on the fundamentals of laparoscopic surgery suturing model, and were tested in the animal operating room (OR) on a Nissen fundoplication model after training. Performance and workload scores were recorded at baseline, after proficiency achievement, and during the test. Performance, NASA-TLX scores, and inadvertent injuries during the test were analyzed and compared. Workload scores declined during training and mirrored performance changes. NASA-TLX scores correlated significantly with performance scores (r = -0.5, P < 0.001). Participants with higher workload scores caused more inadvertent injuries to adjacent structures in the OR (r = 0.38, P < 0.05). Increased mental and physical workload scores at baseline correlated with higher workload scores in the OR (r = 0.52-0.82; P < 0.05) and more inadvertent injuries (r = 0.52, P < 0.01). Increased workload is associated with inferior task performance and higher likelihood of errors. The NASA-TLX questionnaire accurately reflects workload changes during simulator training and may identify individuals more likely to experience high workload and more prone to errors during skill transfer to the clinical environment.
Article
The aim of this study was to identify the magnitude and characteristics of work-related musculoskeletal complaints among perioperative nurses and technicians (PNT) and determine the associated ergonomic risk factors in the operating room (OR) environment based on self-report and focus group discussion. The 50 PNTs who participated in the study completed a self-report survey for musculoskeletal symptoms, Job Description Questionnaire, and Psychometric Evaluation Questionnaire, and participated in focus groups to discuss potential OR ergonomic risk factors. The results of the study demonstrated a high prevalence of work-related musculoskeletal disorders (WMSD) among PNTs, with lower back pain the most prevalent (84%) complaint, followed by ankle/foot (74%) and shoulder (74%) pain. In addition, lower back pain (31%), followed by ankle/knee (24%) pain were found to be the main causes of absenteeism from work. Participants suggested simple ergonomic and engineering solutions can be adopted to improve the work environment of PNTs.
Article
To compare some psychophysiological responses to arm exercise with those to leg exercise, an experiment was carried out on electronically braked bicycle ergometers, one being adapted for arm exercise. Eight healthy males took part in the experiment with stepwise increases in exercise intensity every 4 min: 40—70—100—150—200 W in cycling and 20—35—50—70—100 W in arm cranking. Towards the end of each 4 min period, ratings of perceived exertion were obtained on the RPE scale and on a new category ratio (CR) scale: heart rate (HR) and blood lactate accumulation (BL) were also measured. The responses obtained were about twice as high or more for arm cranking than for cycling. The biggest difference was found for BL and the smallest for HR and RPE. The incremental functions were similar in both activities, with approximately linear increases in HR and RPE and positively accelerating functions for CR (exponents about 1.9) and BL (exponents 2.5 and 3.3 respectively). When perceived exertion (according to the CR scale) was set as the dependent variable and a simple combination of HR and BL was used as the independent variable, a linear relationship was obtained for both kinds of exercise, as has previously been found in cycling, running, and walking. The results thus give support for the following generalization: For exercise of a steady state type with increasing loads the incremental curve for perceived exertion can be predicted from a simple combination of HR and BL.
Article
During manual handling, the back muscles protect the spine from excessive flexion, but in doing so impose a high compressive force on it. Epidemiological links between back pain and repetitive lifting suggest that fatigued muscles may adversely affect the balance between bending and compression. Fifteen volunteers lifted and lowered a 10 kg weight from floor to waist height 100 times. Throughout this task, the bending moment acting on the osteoligamentous lumbar spine was estimated from continuous measurements of lumbar flexion, obtained using the 3-Space Isotrak. Spinal compression was estimated from the electromyographic (EMG) activity of the erector spinae muscles, recorded from skin-surface electrodes at the levels of T10 and L3. EMG signals were calibrated against force when subjects pulled up on a load cell, and correction factors were applied to account for changes in muscle length and contraction velocity. Fatigue in the erector spinae muscles was quantified by comparing the frequency content of their EMG signal during static contractions performed before, and immediately after, the 100 lifts. Results showed that peak lumbar flexion increased during the 100 lifts from 83.3 +/- 14.8% to 90.4 +/- 14.3%, resulting in a 36% increase in estimated peak bending moment acting on the lumbar spine (P = 0.008). Peak spinal compression fell by 11% (p = 0.007). The median frequency of the EMG signal at L3 decreased by 5.5% following the 100 lifts (p = 0.042) confirming that the erector spinae were fatigued, but measures of fatigue showed no significant correlation with increased bending. We conclude that repetitive lifting induces measurable fatigue in the erector spinae muscles, and substantially increases the bending moment acting on the lumbar spine.