International Journal of Industrial Ergonomics最新文献

While performing orthopedic surgeries, surgeons stand for long hours, carrying out repetitive and/or forceful movements, in sustained awkward postures, increasing the risk of work-related musculoskeletal disorders (WRMSD).

Nonetheless, the literature addressing the risk factors, prevalence and symptoms of lower limb WRMSD remains dispersed and lacks a comprehensive synthesis. However, considering the critical role of lower limbs in maintaining surgical stability and balance, WRMSD affecting lower limbs could significantly compromise precision and motor skills, potentially impacting surgery outcomes.

This systematic review addresses this gap by consolidating evidence on lower limb WRMSD incidence and symptoms among orthopedic surgeons, while identifying the underlying risk factors.

The selection of the papers for this systematic review follows the PRISMA methodology and includes articles from Scopus, PubMed, and Web of Science published between 2013 and 2023. Among 320 articles initially identified, 14 met the inclusion criteria.

This systematic review shows knee WRMSD symptoms as the most prevalent, followed by foot/ankle and hip/thigh symptoms. The prevalence of foot/ankle WRMSD was the highest, followed by knee/lower leg and hip/thigh WRMSD. Additionally, the main risk factors reported as contributing to the development of these disorders included prolonged standing, static postures, higher body mass index, aging, smoking, and years of experience.

The findings of this systematic review highlight the substantial prevalence of lower limb WRMSD and symptoms among orthopedic surgeons and shed light on the associated risk factors. Understanding these factors is crucial for devising preventive measures and ergonomic interventions, ultimately enhancing the well-being of surgeons, and improving patient care.

Repetitive use of handheld nutrunners contributes to the development of musculoskeletal disorders (MSDs) among assembly operators. Tool-using organizations control the physical exposures resulting from nutrunners through their own, company-specific methods and recommendations. The aim of this study was to explore an automotive organization's current practice when conducting ergonomics assessments of nutrunner use. Fourteen employees representing different professional roles within the automotive manufacturing organization were interviewed about their involvement in, and approaches to, ergonomics evaluations of nutrunners. Findings show that the objective criteria tightening torque and tool type are combined with the operators' subjective assessments of the load to identify MSD risks associated with nutrunner use. This way, the effects of factors such as working posture could be integrated into the assessment. Further, it was found that information and knowledge availability could influence the resulting exposures estimates, where for example information about how to appropriately select tool settings is not readily available. In addition, there are negotiating criteria such as quality considerations which need to be balanced with health and safety management, influencing the physical demands associated with power tools.

Relevance to industry

By providing insight into an automotive manufacturer's approach to managing and assessing handheld tightening tools, policy-makers can form recommended limits and methods for standardized assessments of reaction load exposure from nutrunners.

Interactive large-scale displays have significant potential for information visualization and collaborative interactions, particularly in educational and technological demonstrations. In these scenarios, usually a presenter communicates with spectators while allowing them to engage in various tasks. We propose a lightweight display interaction solution that enables multiple user interactions and facilitates natural interactions with objects in virtual environments, such as navigation and basic actions. A study involving 20 volunteers was conducted to assess the system performance and accessibility through object manipulation tasks such as selecting, moving, rotating, and zooming in a virtual environment. The results were compared to those obtained with a head-mounted display. The study found that (1) there was no significant difference in task execution time or precision and (2) the new method was more convenient, intuitive, and preferred by users.

The touchscreen has the potential to optimize the space usage and efficiency of the flight deck. Currently, touchscreens can combine the input and output functions of different systems. However, it does not yet serve as an inceptor to replace the sidestick or control column for aircraft manoeuvres. This study aims to examine the potential of a touchscreen as a flight inceptor compared with a traditional sidestick and gamepad. This research recruited 72 participants who interacted with three inceptors for both an instrument landing with disturbance and without disturbance using the Future System Simulator. The findings demonstrated that pilot performance, system usability and pilots’ situation awareness of touchscreen inceptors were significantly inferior to those of traditional sidesticks and gamepads. Compared to the sidestick and gamepad, the touchscreen provided a poorer situation awareness with the highest supply and demand. In addition, the performance of all inceptors was significantly influenced by disturbance. There is still a long way to go for certification of a touchscreen as an inceptor on the future flight deck. This research showed that even though the touchscreen inceptor scored the lowest on both SUS and SART, the majority of pilots agreed that the touchscreen inceptor provided a better attentional supply in challenging disturbance circumstances, providing proof of concept for its possible inclusion in flight deck design. There is a potential that the emerging touchscreen as an inceptor may develop further along with human-system integration flight deck design.

Railway dispatchers are prone to mental fatigue due to prolonged periods of intense concentration. As the main or even the only light source in the enclosed control centers, artificial lighting has non-visual effects on human alertness, cognition, and mood. To investigate whether external environmental cues could counteract performance decline induced by endogenous cardiac exhaustion, the current study modulated four correlated color temperature (CCT) levels and developed one visual task and six cognitive tasks representing basic and advanced cognitive functions, including sustained attention, response inhibition, working memory, risk decision-making, executive control, and emotion perception. A within-subjects design was employed to collect subjective and behavioral responses under both normal and fatigued mental antecedent states. Electroencephalogram (EEG) with alpha and theta bands as well as four fatigue-related algorithms including θ/β, α/β, (θ+α)/β, and (θ+α)/(α+β) were analyzed to explore the underlying neural mechanisms behind these responses. The results indicated a complex interactive pattern of CCT and mental antecedent state on alertness, cognition, and mood. Higher CCT had a supportive effect on subjective alertness and positive mood, independent of mental antecedent state. However, it exhibited a slight performance-impairing effect on sustained attention tasks. Conversely, higher CCT demonstrated a significant enhancement in advanced cognitive functions for fatigued individuals. EEG data revealed alpha oscillations increased, but theta activity and (θ + α)/β suppressed at 12,000 K, suggesting higher CCT partially alleviated the decline in alertness and cognition induced by mental fatigue. To develop an appropriate photobiological lighting scheme for fatigue intervention, larger and longer-term studies are needed in the future to measure a range of confounding factors and individual differences.

Touchscreen in-vehicle central control interfaces are rapidly replacing traditional physical buttons. However, the differences in the effects of tactile feedback between touchscreens and physical buttons on driver emotions are unclear. This study used a simulated driving experiment to investigate the effects of tactile feedback mode and intensity on driver emotion using the Self-Assessment Manikin (SAM). The results showed that tactile feedback mode, intensity, and difficulty of non-driving-related tasks (NDRTs) significantly affected drivers' emotional states. Touchscreen tactile feedback elicited a more positive emotional state than physical button tactile feedback. The intensity of touchscreen tactile feedback is positively correlated with driver emotional valence. However, higher-intensity physical button feedback decreases driver emotional valence, particularly when drivers are engaged in complex NDRTs, and the difference due to feedback intensity is insignificant. The study's results could help automakers intervene by designing tactile feedback to enhance the emotional experience of the driver's in-vehicle interaction interface.

The purpose of this study was to determine the maximal biomechanical and physiological effects of implementing an active sitting protocol while using an active chair, compared to the use of a traditional office chair, and standing workstation. The active chair had a seat pan split longitudinally, enabling the participant to pedal their feet while seated. The active sitting protocol consisted of participants actively plantarflexing and dorsiflexing their ankles in a “stepping” motion to the sound of a metronome, operating at 40 beats per minute. Twenty-four healthy participants performed computer tasks at each of the workstations for 30-min. For each collection period, participants’ biomechanical and physiological responses were recorded using electromyography (EMG); near-infrared spectroscopy (NIRS); pressure distribution mats; electrodermal activity (EDA); heart rate (HR) monitor; and subjective discomfort survey. Statistical analysis was conducted using a repeated measures analysis of variance, with a Tukey correction post-hoc analysis for significant findings. There were few significant findings in our biomechanical measures that separated the active chair from the traditional office chair and the standing workstation. However, this study demonstrated that the active sitting protocol had positive physiological effects for the user, with the greatest benefit being the significant increase in blood oxygenation levels to the gastrocnemius.

Cognitive health screening for aviators would assist in managing a shortage of experienced pilots. Extending pilot careers by optimizing their cognitive health would address both the number and quality of pilots available for airline and general aviation operations. The present work tested the validity of an online screening tool for pilots that measures aviation domain-relevant cognition. Sixty-five licensed pilots (18–80 years, M = 48.8, SD = 16.3) with varying levels of experience completed a 30-min online cognitive health screening tool for pilots. Risk status was determined via a novel metric using self-reported incidents. Machine learning algorithms identified the cognitive factors most useful in identifying pilots with increased risk for accidents and serious incidents. Support vector machines and boosted decision tree algorithms provided the most reliable and strongest classifications models of pilot risk. Findings support the use of this short online screening tool for highlighting performance issues with domain-relevant cognitive abilities based on the Dynamic Mental Model for pilots, such as situation awareness and prospective memory. Understanding personal cognitive challenges is the basis for customized skill maintenance designed to augment cognition for those interested in safely extending their piloting careers.

A variety of interaction devices are increasingly used for human-computer interaction (HCI) tasks in ship vibration conditions, but have seldom been well assessed. This study aimed to examine task performance, upper limb muscle activity, and perceived fatigue and device usability for four typical interaction devices (i.e., mouse, trackball, touchscreen, and Leap Motion) under simulated ship vibration conditions. A two-factor within-subjects design was employed in this study, where participants performed basic HCI tasks with the four interaction devices under three conditions (i.e., static condition, and low and high vibration conditions). The results showed that vibration condition significantly reduced task performance, especially for Leap Motion. Differences in task performance, upper arm and shoulder muscle activities, perceived fatigue and device usability were found among interaction devices. Mouse and touchscreen achieved the best task performance, compared with trackball and Leap Motion, while both touchscreen and Leap Motion achieved larger upper limb muscle activities, compared with trackball and mouse.

Relevance to industry

The findings provide important implications for the use and configuration of interaction devices, and for the development of prevention interventions for risks of musculoskeletal disorders in using interaction devices under ship vibration conditions.

Repeated high-g shocks and whole-body vibration (WBV) as experienced by operators of High-Speed Craft (HSC) increase the risk of fatigue, back pain, and acute and chronic injuries, especially in the lumbar region of the spine. Studies on abdominal belts have suggested their beneficial effects on lumbar torso stabilisation and back pain mitigation in both weight lifting and HSC scenarios. This paper presents a human musculoskeletal model to simulate belt effects for occupants on HSC under high-g shocks. Parameters included the shock severity with peak acceleration ranging from 3 g to 10 g, human dimensions and muscle strengths, the belt width and belt forces are investigated. The results show an average of 120% increase in the intra-abdominal pressure (IAP), a 9% reduction in the transverse abdominis activities, and a 12% reduction in the spinal compressive force at the L4/L5 joints when the abdominal belt is added to the human model. In conclusion, wearing an abdominal belt significantly assists abdominal muscles and maintains a solid core during intense WBV generated in different shock severity levels. It may cause a small negative influence on the neck region with a 2.4% increase in the shear force at the C4/C5 joints.