Rapid Upper Limb Assessment Research Articles

Risk Factors for Developing Occupational Back Pain in Electronics Industry Workers: A Cross-Sectional Study

Back pain is an occupation-related problem among workforces. This cross-sectional study aimed to identify the prevalence of back pain and the risk factors of occupational back pain among workers in the electronics industry. In total, 354 electronics workers in Thailand participated in the study. Data were collected using the Musculoskeletal Disorders Severity and Frequency Questionnaire, the Job Content Questionnaire, and ergonomics risk assessment via the Rapid Upper Limb Assessment (RULA). Risk factors of back pain were identified by multiple logistic regression analysis, providing adjusted odds ratios (ORadj) and 95% confidence intervals (95% CI). The study found that most workers were operators (92.09%) and had repetitive work (83.62%). A high ergonomics risk was observed in workers who stood during work (68.49%) and operated machines (71.70%). The 1-month prevalence of developing back pain was 20.62% and the significant factors correlated with back pain were low levels of job control and decision-making (ORadj = 2.26; 95% CI [1.26 ,4.05]), lack of exercise (ORadj = 8.30; 95% CI [1.35, 24.28]), repetitive work (ORadj = 2.94; 95% CI [1.19, 7.29]), and high ergonomic risk level (ORadj = 2.81; 95% CI [1.16, 5.07]). These findings suggest that measures should be implemented by empowering electronics workers to make decisions and control their jobs, as well as promoting health through muscle-stretching exercise, to support back pain prevention.

Mismatch between fixed classroom furniture and anthropometric measurements among university students: Relationships to ergonomic risk.

Appropriate arrangement of classroom ergonomics is necessary for maintaining health and improving academic performance, learning, and motivation. We aimed to determine the anthropometric measurements and ergonomic risk levels of students during a handwriting activity on a fixed desk and chair and to analyze the mismatch and relationships between these factors. This study included 149 university students (female:73, male:76). Anthropometric measurements (lower and upper extremity length, shoulder height, elbow-rest height, hip-popliteal length, popliteal height, knee height, the distance between tragus and wall, and between acromion and wall) were done with a tape measure. The Rapid Upper Limb Assessment (RULA) tool was conducted to determine the ergonomic risk level while students wrote a standard text on a fixed desk and chair as if they were taking notes in the classroom. The mismatch was evaluated between backrest height and sitting shoulder height, seat height, and popliteal height. The Pearson Chi-Square and the Spearman Correlation test were used for statistical analysis. The median values of the participants' age, height, weight, and BMI were 22 years, 1.70 m, 68 kg, and 23.18 kg/cm2, respectively. Most students had inadequate ergonomic posture while writing on fixed furniture at the university (Median RULA grand score: 4). More mismatches for seat height (54.4%) were found in high ergonomic risk levels but mismatches for backrest height did not follow a similar result. More investigation should be conducted with prospective studies including interventions like adjustable furniture.

Engineering ergonomic risk assessment of karate choku zuki straight punch

This study utilizes the Rapid Upper Limb Assessment (RULA) technique to evaluate suggested improvements aimed at enhancing the safety and efficacy of the Choku Zuki (Straight Punch), a high-risk karate exercise. The primary objective is to identify and address potential musculoskeletal issues associated with this technique. Given the prevalence of musculoskeletal injuries in sports, particularly in activities with high intensity like karate, the need for reliable ergonomic risk assessment tools such as RULA is paramount. By applying RULA to analyze the ergonomic aspects of the Choku Zuki punch, this study provides crucial insights into potential areas of concern. It identifies specific postures and movements that may predispose practitioners to injury, allowing for the development of targeted interventions to mitigate risks and enhance safety. Furthermore, this research underscores the importance of integrating ergonomic considerations into sports training regimens to optimize performance and minimize injury risks. Beyond its implications for karate training, the study emphasizes the broader significance of ergonomic assessments in sports science and engineering. It showcases how engineering methodologies can be leveraged to improve the safety, efficiency, and overall performance of sporting activities, fostering collaboration between sports scientists, engineers, athletes, coaches, and healthcare professionals to advance sports performance and safety standards.lities.

Ergonomic Evaluation and Design of Workstation for Gemstone Polishing Workers

Background: Many researchers have stated that workers working in unorganized sectors are at risk of musculoskeletal disorders (MSDs), like back pain, wrist pain, pain in the neck and shoulders, etc. Ergonomic study of these workstations is necessary for the analysis of workrelated disorders. Methods: In this study on MSDs among gemstone workers in Jaipur, Rajasthan; a modified Nordic questionnaire was employed. Further analysis was done using the 'Ergonomic Design and Analysis’ module of DELMIA. Rapid Upper Limb Assessment (RULA) analysis was used. Results: The survey showed lower back pain among 81.25% of workers. Neck pain, hips or thigh pain, and ankle or feet pain were observed among nearly half of the surveyed workers, leading to further investigation. RULA analysis confirmed the results of the survey; the final RULA score came out to be 7. This score means investigation and changes are needed immediately. The workstation was designed using standard anthropometric data for the Indian population and modeled in CATIA. The modified workstation was analyzed using DELMIA, which has shown a RULA score of 3. Conclusion: The survey results and RULA analysis in DELMIA of gemstone polishing workers have shown that gemstone polishing is a highly risky profession. Musculoskeletal risk factors, like low back pain, neck pain, and wrist pain, have also been found to be present among the workers. The gemstone polishing workstation needs design interventions using Indian anthropometric data to reduce the risk of musculoskeletal disorders. RULA analysis of an anthropometrically modified workstation showed the modified workstation to be ergonomically fit.

Postural Risks in Dental Practice: An Assessment of Musculoskeletal Health.

In recent years, Romania's stomatology private practice sector has seen substantial growth, with many dentists fully committing to building and expanding their own practices, often funded by their personal income. This study aimed to explore how various postures affect the muscle groups of dentists (380), particularly focusing on identifying positions that may jeopardize their musculoskeletal health. A group of dentists effectively participated in this study (10), adhering to their regular work routines while wearing wearable sensors on their backs to monitor posture and activity. The data gathered from these sensors were analyzed using the RULA (rapid upper-limb assessment) and REBA (rapid entire-body assessment) tools. The findings indicated that the head and shoulder movements during dental procedures involved considerable and repetitive angular shifts, which could strain the neck and back muscles and heighten the risk of musculoskeletal problems. Additionally, the standing postures adopted by the dentists were associated with an increased risk of postural issues and greater overall fatigue. Extended periods of trunk and head tilting were also identified as contributing factors to posture-related challenges.

Hand Tool Intervention for Rubber Tappers Using Modified Michie Golledge Knife

ABSTRACT Background and Objectives Rubber tapping is a physically demanding and skilled agricultural operation that can cause musculoskeletal disorders (MSDs). This research investigated the impact of using an ergonomically modified rubber tapping knife on the hand posture of rubber tappers. Methods Initially, a postural assessment was conducted using CATIA V6 modelling software followed by a non-randomized longitudinal study with 32 rubber tappers. In the second phase, the study used a custom-modified Standard Nordic Questionnaire, video recordings, and direct observations. The study compared the results of the ergonomically modified rubber tapping knife with the traditional tapping knife, evaluating hand grip strength, endurance time chip thickness, time required to complete 300 trees, and posture using the Rapid Upper Limb Assessment (RULA) tool. Results Compared to pre-tapping values, the mean reduction in grip strength after tapping was significantly less with the modified rubber tapping knife than with the traditional tapping knife (2.96 kg, SD 0.85 kg vs 7.31 kg SD 2.13 kg). Similarly, the reduction in hand endurance time was less with the modified knife than with the traditional knife (1.78 seconds, SD 0.47 seconds vs 3.34 seconds, SD 0.87 seconds). The study also indicated that the modified knife did not significantly affect chip thickness. Additionally, a slight increasing in tapping time was observed with the ergonomically modified knife, which may be attributed to a learning curve phenomenon. This suggests that as rubber tappers become more accustomed to the new tool, their efficiency may improve over time. Conclusion The hand grip strength and endurance time was significantly lower with the ergonomically modified tapping knife. The study concluded that using an ergonomically modified tapping knife led to a significant improvement in hand posture among rubber tappers.

Assessment of Posture Related Risks among Goldsmiths Using Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA)

Assessment of Posture Related Risks among Goldsmiths Using Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA)

Human body features recognition based adaptive user interface for extra-large touch screens

With the widespread use of extra-large touch screens (eLTS) in various settings such as work and education, interaction efficiency and user experience have garnered increased attention. The current user interface (UI) layouts of eLTS are primarily categorized into two modes: fixed position and manual adjustment. The fixed UI layout fails to accommodate users of different heights and sizes, while the manual adjustment mode involves cumbersome steps and lacks sufficient flexibility. This study proposes an adaptive UI for eLTS. The optimal operational area on the eLTS is determined based on users’ height, eye level, arm length, face orientation, and distance from the screen. The eLTS menu is then positioned and displayed within this optimal area. Simulations involving users of various heights (P1 female, P50 male and female, and P99 male) were conducted to evaluate fatigue using the rapid upper limb assessment (RULA) method. The results indicate that the proposed adaptive UI significantly reduces user fatigue.

Postural analysis and ergonomic intervention of unorganized workers in indian construction sectors.

In India's fast-growing economy, the construction sector offers significant developments with huge employment opportunities but poses risks due to poor working environments and uncomfortable postures. Traditional methods, such as manual material handling, can lead to health hazards and musculoskeletal disorders such as overexertion, low back pain, etc. The purpose of this study was to analyze the working postures of unorganized employees engaged in residential buildings using Ergofellow software and to recommend changes in their unsafe working postures. Participants' working positions were video recorded and the postures were analyzed using Rapid Upper Limb Assessment (RULA), Rapid Entire Body Assessment (REBA) and Ovako Working Posture Analysis (OWAS). Paired sample t-tests were used to analyze significant differences between the RULA and REBA scores after the ergonomic interventions were implemented. From the analysis of RULA, REBA and OWAS, the working postures showed a high risk of potential injury and required an immediate change in employees' working postures. The RULA and REBA scores were subsequently lower after the ergonomic interventions, which were based on ergonomic and safety principles. The paired sample t-tests with p-values of less than 0.05 demonstrated decreased risks after ergonomic interventions. Working postures of the construction workers exposed to musculoskeletal disorders were examined and the ergonomic interventions were implemented. According to the recommendations, working positions were changed, and employee well-being was enhanced by reduced operational risks.

Investigation of musculoskeletal symptoms, work postures, quantification of muscle activity, and estimation of grip/push forces among sonographers

AbstractDue to the physical nature of their work, sonographers are exposed to many musculoskeletal disorder risk factors, including awkward posture, repetitive movements, forceful manual exertion, and static muscle contractions, especially in the upper limbs. The current study is an investigation of musculoskeletal disorders among sonographers, caused by various occupational risk factors via different sonographic scan types. During the first phase of this study, the musculoskeletal symptoms and work postures of 29 subjects were investigated. During the second phase, muscle activity was quantified, and grip/push forces were estimated using the data obtained from 10 volunteer sonographers. 82% of sonographers experienced musculoskeletal symptoms. Based on the final scores and action levels obtained via rapid upper limb assessment, while performing scans of left regions; ergonomic changes and interventions were found necessary, to relieve stress on the sonographer's body. The results of muscular activity per muscle and scan type, showed that the mean muscle activity of the middle deltoid muscle was significantly higher during the right abdominal scan (17.64% maximum voluntary contraction [MVC]), compared to those of thyroid (12.54% MVC) and left abdominal (7.32% MVC) scans. Additionally, mean grip and push forces during both abdominal scans were significantly higher than those during the thyroid scan. Despite an injury risk during all scans, risk factor impact was different among scan types. This groundbreaking study represents the first that captures and measures both grip and push forces simultaneously, which may prove helpful while investigating corrective interventions or optimizing design of sonography robots and ergonomic probes in future studies.

Engineering Ergonomic Risk Assessment of Karate Choku Zuki Straight Punch

This study utilizes the Rapid Upper Limb Assessment (RULA) technique to evaluate suggested improvements aimed at enhancing the safety and efficacy of the Choku Zuki (Straight Punch), a high-risk karate exercise. The primary objective is to identify and address potential musculoskeletal issues associated with this technique. Given the prevalence of musculoskeletal injuries in sports, particularly in activities with high intensity like karate, the need for reliable ergonomic risk assessment tools such as RULA is paramount. By applying RULA to analyze the ergonomic aspects of the Choku Zuki punch, this study provides crucial insights into potential areas of concern. It identifies specific postures and movements that may predispose practitioners to injury, allowing for the development of targeted interventions to mitigate risks and enhance safety. Furthermore, this research underscores the importance of integrating ergonomic considerations into sports training regimens to optimize performance and minimize injury risks. Beyond its implications for karate training, the study emphasizes the broader significance of ergonomic assessments in sports science and engineering. It showcases how engineering methodologies can be leveraged to improve the safety, efficiency, and overall performance of sporting activities, fostering collaboration between sports scientists, engineers, athletes, coaches, and healthcare professionals to advance sports performance and safety standards.lities.

Preliminary Evaluation of New Wearable Sensors to Study Incongruous Postures Held by Employees in Viticulture.

Musculoskeletal Disorders (MSDs) stand as a prominent cause of injuries in modern agriculture. Scientific research has highlighted a causal link between MSDs and awkward working postures. Several methods for the evaluation of working postures, and related risks, have been developed such as the Rapid Upper Limb Assessment (RULA). Nevertheless, these methods are generally applied with manual measurements on pictures or videos. As a consequence, their applicability could be scarce, and their effectiveness could be limited. The use of wearable sensors to collect kinetic data could facilitate the use of these methods for risk assessment. Nevertheless, the existing system may not be usable in the agricultural and vine sectors because of its cost, robustness and versatility to the various anthropometric characteristics of workers. The aim of this study was to develop a technology capable of collecting accurate data about uncomfortable postures and repetitive movements typical of vine workers. Specific objectives of the project were the development of a low-cost, robust, and wearable device, which could measure data about wrist angles and workers' hand positions during possible viticultural operations. Furthermore, the project was meant to test its use to evaluate incongruous postures and repetitive movements of workers' hand positions during pruning operations in vineyard. The developed sensor had 3-axis accelerometers and a gyroscope, and it could monitor the positions of the hand-wrist-forearm musculoskeletal system when moving. When such a sensor was applied to the study of a real case, such as the pruning of a vines, it permitted the evaluation of a simulated sequence of pruning and the quantification of the levels of risk induced by this type of agricultural activity.

Comfort evaluation of carrier-based aircraft missile handling operation based on fuzzy analytic hierarchy process

The analysis and evaluation of missile handling operation are crucial for ensuring safety and reliability during these processes. This paper proposes a novel assessment method for missile handling motions based on the Fuzzy Analytic Hierarchy Process (FAHP). The methodology comprises several stages: Initially, an analysis of missile handling motions is conducted. Subsequently, joint evaluation indicators influencing operational comfort are selected. Following this, membership functions and a comprehensive evaluation matrix are constructed. Finally, a fuzzy comprehensive evaluation model for the comfort level of carrier-based aircraft ammunition handling operations is established. A typical case study of carrier-based aircraft missile handling operation is presented to illustrate the fuzzy comprehensive evaluation process. The evaluation results are then compared with those obtained from the Rapid Upper Limb Assessment (RULA) and Ovako Working Posture Analysis System (OWAS) models. Comparative analysis indicates that the results derived from the fuzzy comprehensive evaluation model demonstrate high reliability.

Preventing Surgeon Work-Related Musculoskeletal Disorders: A Pilot Study of the Comprehensive Operating Room Ergonomics (CORE) Program.

Work-related musculoskeletal disorders (WMSDs) among surgeons are markedly increasing. Several proposed interventions to reduce WMSDs among surgeons have been studied, but few follow an occupational therapy-oriented approach addressing biomechanical, psychophysical, and psychosocial risk factors. To design, implement, and assess the potential of the Comprehensive Operating Room Ergonomics (CORE) program for surgeons, a holistic evidence-based ergonomics and wellness intervention grounded in occupational therapy principles. Mixed-methods pilot study with the quantitative strand embedded in the qualitative strand. University-affiliated hospital. Six laparoscopic surgeons. CORE program outcomes were assessed using qualitative and quantitative data to indicate changes in posture, physical discomfort, sense of wellness, and operating room (OR) ergonomic performance. The Rapid Upper Limb Assessment (RULA) was used to quantify surgeons' WMSD risk level before and after intervention. There were 12 baseline observations (two for each participant), and two or three post-CORE implementation observations. A statistically significant difference, F(1, 6) = 8.57, p = .03, was found between pre- and post-occupational therapy intervention RULA scores. Thematic analysis of surgeon feedback, which was overwhelmingly positive, identified five themes: postural alignment, areas of commonly reported physical pain or discomfort, setup of the OR environment, surgical ergonomics training, and ergonomics in everyday life. The CORE program effectively decreased ergonomic risk factors to optimize surgeons' occupational performance in the OR. This study demonstrates a potential solution to how occupational therapists can holistically support surgeons and health care providers who are at risk for WMSDs. Plain-Language Summary: By 2025, a surgeon shortage is expected, partly because of the increase in surgeons' work-related musculoskeletal disorders, which affect their health and job continuity. This pilot study shows that the Comprehensive Operating Room Ergonomics program effectively addresses these problems. The study also serves as a framework for occupational therapy professionals to work with health care providers on ergonomics, benefiting population health. Results suggest that this approach could enhance surgeons' work conditions, supporting the American Occupational Therapy Association's Vision 2025 to improve health and quality of life.

Ergonomic Risk Assessment and Mitigation Strategies for Retail Workers: Insights from a Case Study in Dungun

Manual handling activities contribute to 40% of musculoskeletal disorders (MSDs), leading to long-term discomfort, disability, medical costs, and financial hardships for workers, while employers face lower productivity and compensation costs. An ergonomic assessment was conducted among employees at ABC Hardware in Dungun to identify ergonomic risk factors, determine the likelihood of harm affecting workers' musculoskeletal health, and recommend control measures to improve workers' health and well-being. Utilizing a combination of interviews, observations, and questionnaires based on established ergonomics guidelines, the research highlights the prevalence of MSDs among workers engaged in manual handling tasks, emphasizing the need for ergonomic interventions and awareness to enhance workplace safety and employee well-being. Findings from the ergonomic assessment revealed significant discomfort and risk factors related to awkward postures, repetitive motions, forceful exertion, and static positions. Specific ergonomic issues identified include discomfort in the upper back, thighs, and knees among storekeepers, and neck and lower back pain among warehouse workers. Service desk representatives were found to experience discomfort related to static postures and repetitive motions. The study recommends advanced ergonomic assessments such as Rapid Entire Body Assessment (REBA), Occupational Repetitive Assessment (OCRA), and Rapid Upper Limb Assessment (RULA), along with improvements in ergonomic practices and tools. Implementing job rotation, providing ergonomic equipment, and conducting training on proper lifting techniques are essential to address the identified risks. This research highlights the critical role of ergonomic practices in preventing MSDs and improving overall workplace safety.

A Product Evaluation of Augmented Reality Equipment Coupled to Diagnostic Medical Sonography: A Potential Equipment and Ergonomic Innovation

Objective: The aim of this product evaluation was to investigate the workflow and occupational health benefits of implementing augmented reality (AR) technology (MediView XR Inc, Cleveland, OH) paired with a portable ultrasound equipment system. Materials and Method: A diverse sample of sonography users was consented and ranged in experience levels. They were asked to complete a video training session, a hands-on demonstration, and remote instruction while using the augmented reality ultrasound (AR US) system. The duration of participants’ tasks was assessed during the use of both AR US and the 2-dimensional ultrasound (2D US) system. Participants’ postures and positions were evaluated using the Rapid Upper Limb Assessment (RULA), which assessed ergonomic risk factors, linked to body position and muscle usage. Participants also completed the System Usability Scale (SUS). Finally, participants were invited to complete a qualitative interview session, regarding the use of the AR US system. Results: A total of 20 participants provided data after using both the AR US and 2D US systems. The assessment data revealed positive SUS scores, which reflected favorably on both the product, education, and the training provided. The time spent on simulated work (20 minutes), with both imaging systems, remained consistent. The Rapid Upper Limb Assessment tool (RULA) scores for the cohort indicated a lower (better) median upper body score when using the AR US system. The cohort also had a statistically significant lower median subscore for the neck, trunk, and legs, compared with 2D US ( p < 0.00). Conclusion: Although larger studies are necessary to validate these findings, this cohort identified several opportunities for integrating the AR US system. Preliminary evidence suggests that an AR US system may offer occupational health benefits, as part of the imaging workflow.

Risk Assessment of Rubber Tapping A Case Study: Pa Phayom District, Phatthalung Province, Thailand

This cross-sectional study investigated the risks of rubber tapping among rubber farmers in Pa Phayom District, Phatthalung Province, Thailand, utilizing the EART (Ergonomic Risk Assessment Tool for Rubber Tappers) and RULA (Rapid Upper Limb Assessment) approaches. Purposive sampling was utilized to randomly choose 154 rubber farmers, aged 20 to 60 to serve as the sample group. They met the inclusion requirements of being in excellent health, being able to read and write Thai fluently, not having a history of back discomfort or injuries, and having at least a year of experience tapping rubber. The results showed that the mean RTL value was 415, SD = 182, while the mean RTI value was 1.77, SD = 1.35, with Min = 0.31 and Max = 8.64. The RULA analysis gave scores ranging from 2 to 7 as acceptable risk to high risk, suggesting that rubber farmers should improve their working posture or reduce factors that affect risk to ensure better health outcomes. It was discovered that the EART and RULA can be used as an assessment method to identify ergonomic risk problems in rubber tapping operation. It was suggested that the rubber tapping operation needs to be improved, re-evaluated, and implemented immediately.

Exoscope and Supermicrosurgery: Pros and Cons of 3D Innovation in Lymphatic Surgery.

Background: The surgical treatment of lymphedema has seen advancements in recent years, with supramicrosurgical lymphaticovenular anastomosis (sLVA) gaining global acceptance. The integration of 3D exoscopes into microsurgery offers potential ergonomic and educational benefits. However, systematic evaluation of their efficacy in sLVA remains limited. Methods: A retrospective cross-sectional study was conducted comparing the use of 3D exoscopes to conventional operating microscopes (OM) in sLVA surgeries. Patient data from January 2019 to January 2024 were reviewed, with demographic, clinical, and surgical outcome variables analyzed. Ergonomic assessments were performed using Rapid Entire Body Assessment (REBA) and Rapid Upper Limb Assessment (RULA), while surgeon satisfaction was evaluated through the Microsurgical Intraoperative Satisfaction and Comfort questionnaire (MISCq). Results: An analysis of 25 patients (OM group: n = 14; exoscope group: n = 11) revealed no significant differences in age, sex, etiology, or surgical site between the two groups. Surgical time, number of incisions, and number of anastomoses showed nonsignificant variations between the OM and exoscope groups. Ergonomic assessments indicated potential benefits with exoscope use, particularly for the assistant surgeon. Survey results demonstrated comparable levels of surgeon satisfaction with both instruments, with no significant differences in image quality, contrast, illumination, magnification, visual field, ergonomic maintenance, or stereoscopic orientation. Conclusions: The study suggests that 3D exoscopes are a valuable tool for sLVA supermicrosurgery, offering comparable outcomes to traditional microscopes with potential ergonomic advantages. Their integration into microsurgical practice may contribute to improved surgical comfort and team performance. Further research is warranted to confirm these findings and explore additional factors such as cost-effectiveness and long-term patient outcomes.

Measuring the Effect of an Ergonomic Lecture on the Rapid Upper Limb Assessment Scores of Dental Assistant Students Using Inertial Sensor-Based Motion Capture-A Randomized Controlled Study.

Individuals working in the field of dentistry have a high prevalence of musculoskeletal disorders (MSDs) owing to monotonous and one-sided physical exertion. Inertial measurement units (IMU) are increasingly shifting into focus for assessing postural risk at work. Therefore, the present study aimed to evaluate the effects of an ergonomic lecture and training intervention on postural risk and MSDs in dental assistant students using inertial sensor-based motion capture (MoCap). Eighteen female dental assistant students (age: 19.44 ± 6.83 years; height: 164.59 ± 5.32 cm; weight: 64.88 ± 16.52 kg; BMI: 19.70 ± 4.89 kg/m2), randomly divided into intervention (n = 9) and control (n = 9) groups, participated in the present study. The participants completed the Nordic Questionnaire on MSD prevalence, after which a 90 s MoCap with Xsens IMU was performed. A lecture on ergonomics was provided, followed by a five-week intervention for the intervention group. Follow-up assessments were performed, and 5- and 18-week follow-up MSD questionnaires were administered. Mixed analysis of variance (MANOVA) showed a significant difference in the Rapid Upper Limb Assessment (RULA) and part-scores of the upper arm and wrist. Despite a reduction in MSDs, no significant differences in the time of measurement and groups were detected after the five-week training intervention and the 18-week follow-up questionnaire. A targeted ergonomics lecture was effective for dental assistant students, and technologies such as IMU improved workplace ergonomics in dentists. Further studies with a longer measurement periods, follow-up, and larger sample sizes are recommended.

Electric Wheelchair Manufacturing Analysis For Physical Disabilities Reviewed from the Aspect of Ergonomics

The high rate of physical disability is a trigger and spur in the development of research/research for people with disabilities to help with their daily activities, one of which is with a wheelchair. There is a sense of concern to see manual wheelchairs used daily by people with physical disabilities, especially with their abnormal hands and feet, so it becomes a problem in itself because they are quite tricky and tired of pedaling a manual wheelchair. This condition impacts their work productivity, thereby reducing their income/economy. Therefore, the purpose of this research is to manufacture electric wheelchairs belonging to two people with physical disabilities (i.e., belonging to Bagus and Huda). The ergonomics tests are carried out, including (a) Compatibility of the anthropometry of the user's body and the dimensions of the wheelchair, (b) Results of the user's postural analysis with RULA (Rapid Upper Limb Assessment) (c) Conformity of the dimensions of the wheelchair with the standard, and (d) Evaluation of the usability of the wheelchair based on observation. The results obtained for the Bagus electric wheelchair are from the anthropometric side. The popliteal height is longer than the distance between the seat and the footrest in the wheelchair. For Bagus to be more comfortable in using his wheelchair and for his legs not to be crooked (which will potentially cause more excellent musculoskeletal disorders), it is recommended that the distance between the seat and the footrest be extended. As for Huda electric wheelchairs, in general, they have been modified to adjust to the needs and conditions of Huda's body and make the design of Huda wheelchairs more ergonomic. However, the postural analysis showed that the forearm position was raised, and the hand was twisted when Huda operated the electric wheelchair controller. It is, therefore, recommended to lower the position of the controller in line with the wheelchair mount.