Electromyographic analysis of relevant muscle groups during completion of computer tasks using different computer mouse positions

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.     

The effects of arm posture and holding time on holding capability and muscle activity

The aim of this study was to examine the effects of arm posture and holding time on human holding capability and resulting muscle activity. Fifteen healthy young males were recruited as participants. Maximum holding capacity was examined at 0 (degrees of shoulder forward flexion angle)/90 (degrees of elbow angle), 30/120 and 90/180 arm postures. Maximum acceptable weight of holding was evaluated in three arm postures (0/90, 30/120, 90/180) by three holding times (10?s, 20?s, 30?s). The greatest and lowest maximum holding capacity or maximum acceptable weight of holding occurred at 0/90 and 90/180 arm postures, respectively. Maximum acceptable weight of holding decreased with increasing holding time. While holding maximum acceptable weights, the % of maximum voluntary contraction of brachioradialis, biceps brachii and erector spinae ranged from 14 to 44%, from 14 to 53% and from 25 to 36%, respectively.     

高技能人才工伤保护改进路径

高技能人才由于职业、岗位、才技与众不同,其工伤保护也存在一些特殊性。实践中,并未专门针对高技能人才制定特别的工伤保护措施。为此,笔者分析高技能人才工作时段和场所较易变动、劳动强度较大等特点,提出风险和事故的高发生率是科技活动内在的客观规律等,提出应给予失败者和事故责任者必要的宽容。建议政府应结合不同行业、不同岗位的技术含量和风险特点,从工伤认定、劳动能力鉴定、工伤保险待遇及浮动费率核算几方面改进现有工伤保护政策,且应加强高技能人才工伤预防和促进高技能人才职业康复。结合前文论述,笔者提出了相应政策和实用的对策。     

Analysis of posttraumatic stress disorder in children with road traffic injury in Wenzhou,China

Objective: Road traffic accidents are the leading health threat to children and cause significant long-term mental health problems. This study aimed to characterize posttraumatic stress disorder (PTSD) in children suffering from road traffic injuries (RTIs) in Wenzhou, China.

Methods: We conducted a retrospective study of 537 children (aged 1 to 13 years old) with RTIs. The epidemiological features, PTSD incidence, clinical manifestation, and risk factors were analyzed based on a customized PTSD risk factor questionnaire. The outcome factors were also evaluated by means of the logistic regression method.

Results: The PTSD incidence was 24.77% in children with RTIs. The incidence of PTSD was related to the personality, family environment, and family care of the children. It was found that early psychological intervention and reasonable family care from the family might promote physical and mental welfare as well as contribute to the development of more effective treatments to prevent PTSD.

Conclusion: For susceptible children, in addition to dealing with the somatic injury, psychological intervention and family care should be carried out as early as possible.     

Etiology of fatal thoracic aortic injuries: Secondary data analysis

Objectives: Motor vehicle crashes remain a leading cause of death in the United States (US). Thoracic aortic dissection due to blunt trauma remains a major injury mechanism, and up to 90% of these injuries result in death on the scene. The objective of this study is to understand the modern risk factors and etiology of fatal thoracic aortic injuries in the current US fleet.

Methods: Using a unique, linked, Fatality Analysis Reporting System (FARS) and Multiple Cause of Death (MCOD) database from 2000–2010, 144,169 drivers over 16 years of age who suffered fatal injuries were identified. The merged database provides an unparalleled fidelity for identifying thoracic aortic injuries due to motor vehicle accidents. Thoracic aortic injuries were defined by ICD-10 codes S250. Univariate and multivariate logistic regression models for presence of any thoracic aortic injuries were fitted. Age, gender, BMI weight categories, vehicle class, model year, crash type/direction, severity of crash damage, airbag deployment location, and seatbelt use, fatal injury codes, and location of injury were considered. Odds ratios (OR) and corresponding 95% confidence intervals (95%CI) are calculated.

Results: There were 2953 deaths (2.10%) related to thoracic aortic injuries that met the inclusion criteria. Nearside crashes were associated with an increased odds (OR = 1.42, 1.1-1.83), while rollover crashes (OR =.44,.29-.66) were associated with a reduced odds of fatal thoracic aortic injury. Using backward selection on the full multivariate model, the only significant model effects that remained were vehicle type, crash type, body region, and injury type.

Conclusions: The increased prevalence of fatal thoracic aortic injury in nearside crashes, increasing age, and vehicle type provide some insight into the current US fleet. Important factors, including model year, had significantly lower levels of the injury in univariate analysis, demonstrating the effect of safety improvements in newer model vehicles. Further study of this fatal injury is warranted, including comparisons of those who survive the injury.     

Personal injury recovery cost of pedestrian–vehicle collisions in New South Wales,Australia

Background: There is a need for routine estimates of injury recovery costs from pedestrian collisions using hospital separation records for economic evaluations.

Objective: To estimate the cost of injury recovery following pedestrian–vehicle collisions using the personal injury recover cost (PIRC) equation using key demographic and injury characteristics.

Method: An estimation of the costs of on-road pedestrian–vehicle collisions involving individuals who were injured and hospitalized in New South Wales (NSW), Australia, from 2002 to 2011 using the PIRC equation. The PIRC estimates individual injury recovery costs and does not include costs associated with property damage, vehicle repair, or rescue services. Individual recovery costs associated with severe traumatic brain injury (TBI) were estimated. The injured individual's mean, median, and total injury recovery costs are described for key demographic, injury, and crash characteristics.

Results: There were 9,781 pedestrians who were injured, costing an estimated total of $2.4 billion in personal injury recovery costs, an annual cost of $243 million. Males had a total injury recovery cost 1.7 times higher than females. The median injury recovery cost decreased with increasing age. TBI ($248,491) and spinal cord and vertebral column injuries ($264,103) had the highest median injury recovery costs for the body region of the most severe injury. TBI accounted for 22.6% of the total injury recovery costs for the most severe injury sustained. Just over one third of pedestrians sustained 4 or more injuries, with a median cost of $243,992, which was 1.6 times higher than the cost for a pedestrian who sustained a single injury ($153,682).

Conclusions: Personal injury recovery costs following pedestrian–vehicle collisions where a pedestrian is injured are substantial in NSW. The PIRC equation enables the economic cost burden of road traffic injury to be calculated using hospital separation data. The PIRC enables comprehensive personal injury recovery costs to be estimated and would aid in economic evaluations of preventive strategies in road safety.     

Health burden of serious road injuries in the Netherlands

Background: The consequences of injuries in terms of disabilities and health burden are relevant for policy making. This article provides an overview of the current knowledge on this topic and discusses the health burden of serious road injuries in The Netherlands.

Methods: The overview of current knowledge on disabilities following a road crash is based on a literature review. The health burden of serious road injuries is quantified in terms of years lived with disability (YLD), by combining incidence data from the Dutch hospital discharge register with information about temporary and lifelong disability.

Results: Literature shows that road traffic injuries can have a major impact on victims' physical and psychological well-being and functioning. Reported proportions of people with disability vary between 11 and 80% depending on the type of casualties, time elapsed since the crash, and the health impacts considered. Together, all casualties involving serious injuries in The Netherlands in 2009 account for about 38,000 YLD, compared to 25,000 years of life lost (YLL) of fatalities. Ninety percent of the burden of injury is due to lifelong consequences that are experienced by 20% of all those seriously injured in road accidents. Lower leg injuries and head injuries represent a high share in the total burden of injury as have cyclists that are injured in a crash without a motorized vehicle. Pedestrians and powered 2-wheeler users show the highest burden of injury per casualty.

Conclusion: Given their major impacts and contribution to health burden, road policy making should also be aimed at reducing the number of serious road injuries and limiting the resulting health impacts.     

Organizational networks in road safety: Case studies of U.S. Vision Zero cities

Objective: Each year, more than 30,000 deaths occur on U.S. roads. Recognizing the magnitude and persistence of this public health problem, a number of U.S. cities have adopted a relatively new approach to prevention, termed Vision Zero (VZ). VZ has been adopted by more than 30?U.S. cities and calls for creating a transportation system that ensures that no road traffic crash results in death or serious injury. A core component of VZ is strong multidisciplinary and multisector stakeholder engagement, and cities adopting VZ often establish a VZ coalition to foster stakeholder collaboration. However, there is little information on the structure, development, and functioning of coalitions working to achieve VZ and on tools available to study and evaluate such coalition functioning. We sought to describe the characteristics of prominent U.S. VZ city coalitions and context surrounding VZ uptake and advancement in these cities. Moreover, we demonstrate use of network analysis as one tool for exploring the structure of interorganizational relationships in coalitions.

Methods: We conducted case studies of 4 prominent U.S. VZ city coalitions in 2017–2018. We summarized coalition members’ characteristics and responses to questions about their cities’ VZ adoption, planning, and implementation. We asked each coalition member to provide information on their contact frequency, perceived productivity, and resource sharing with every other coalition member in their city and used network analysis techniques in 2 cities to understand the structures and relationships in coalitions.

Results: Findings indicated that government agencies generally constituted the majority of coalition members and often played central roles in terms of coalition network contact, productivity, and resource flow. Other emerging similarities regarding coalition establishment and VZ implementation included the need for political support, the importance of formal plan development, and increased collaboration and cooperation among partners.

Conclusions: Organizational network analyses, enriched with coalition member interviews, can elucidate key aspects of coalition creation, attributes, and relationship structure. The case studies of leading VZ coalition networks presented here highlight the use of these tools. Ultimately, understanding associations between VZ network structures and attributes and road safety outcomes could help inform effective coalition adoption, implementation, and maintenance to optimize safety outcomes.     

How motorcycle helmets affect trauma mortality: Clinical and policy implications

Background: Motorcycles are the most popular vehicles in Taiwan, where more than 14.8 million motorcycles (1 motorcycle per 1.6 people) are in service. Despite the mandatory helmet law passed in 1997, less than 80% of motorcyclists in Taiwan wear helmets.

Objective: The objective of this study was to analyze the effect of using motorcycle helmets on fatality rates.

Methods: A clinical data set including 2,868 trauma patients was analyzed; the cross-sectional registration database was administered by a university medical center in Central Taiwan. A path analysis framework and multiple logistic regressions were used to estimate the marginal effect of helmet use on mortality.

Results: Using a helmet did not directly reduce the mortality rate but rather indirectly reduced the mortality rate through intervening variables such as the severity of head injuries, number of craniotomies, and complications during therapeutic processes. Wearing a helmet can reduce the fatality rate by 1.3%, the rate of severe head injury by 34.5%, the craniotomy rate by 7.8%, and the rate of complications during therapeutic processes by 1.5%. These rates comprise 33.3% of the mortality rate for people who do not wear helmets, 67.3% of the severe head injury rate, 60.0% of the craniotomy rate, and 12.2% of the rate of complications during therapeutic processes.

Discussion: Wearing a helmet and trauma system designation are crucial factors that reduce the fatality rate.     

The effectiveness of lane departure warning systems—A reduction in real-world passenger car injury crashes

Objective: The objective of this study was to estimate the safety benefits of in vehicle lane departure warning (LDW) and lane keeping aid (LKA) systems in reducing relevant real-world passenger car injury crashes.

Methods: The study used an induced exposure method, where LDW/LKA-sensitive and nonsensitive crashes were compared for Volvo passenger cars equipped with and without LDW/LKA systems. These crashes were matched by car make, model, model year, and technical equipment; that is, low-speed autonomous emergency braking (AEB) called City Safety (CS). The data were extracted from the Swedish Traffic Accident Data Acquisition database (STRADA) and consisted of 1,853 driver injury crashes that involved 146 LDW-equipped cars, 11 LKA-equipped cars, and 1,696 cars without LDW/LKA systems.

Results: The analysis showed a positive effect of the LDW/LKA systems in reducing lane departure crashes. The LDW/LKA systems were estimated to reduce head-on and single-vehicle injury crashes on Swedish roads with speed limits between 70 and 120 km/h and with dry or wet road surfaces (i.e., not covered by ice or snow) by 53% with a lower limit of 11% (95% confidence interval [CI]). This reduction corresponded to a reduction of 30% with a lower limit of 6% (95% CI) for all head-on and single-vehicle driver injury crashes (including all speed limits and all road surface conditions).

Conclusions: LDW/LKA systems were estimated to lower the driver injury risk in crash types that the systems are designed to prevent; that is, head-on and single-vehicle crashes. Though these are important findings, they were based on a small data set. Therefore, further research is desirable to evaluate the effectiveness of LDW/LKA systems under real-world conditions and to differentiate the effectiveness between technical solutions (i.e., LDW and LKA) proposed by different manufacturers.