Background: The authors performed a computerized search of the National Pediatric Trauma Registry for all patients who had compartment syndrome during a 51-month period. Methods: One hundred thirty-three cases were id...Background: The authors performed a computerized search of the National Pediatric Trauma Registry for all patients who had compartment syndrome during a 51-month period. Methods: One hundred thirty-three cases were identified. Boys outnumbered girls 4 to 1. The median age was 12 years and the peak incidence was in the 10-to 14-year-old age group. Results: The most common mechanisms of injury were pedestrians struck by motor vehicles, falls, sports, and occupants in motor vehicle crashes. Eighty-five percent of the cases were the sequelae of fractures. Forearm fractures were the most common cause in the upper extremity, and tibia and/or fibula fractures were most common in the lower extremity. Conclusions: Open fractures significantly increased the risk of developing a compartment syndrome for both forearm and leg fractures. Sixty percent of the patients went directly from the emergency room to the operating room, suggesting that the others developed the compartment syndrome after admission, or had delayed diagnosis.展开更多
Based on economics theory,social value loss caused by vehicle involved in crashes as well as various factors influencing on it were analyzed,the corresponding mi- cro-econometrics model was theoretically given.Moreove...Based on economics theory,social value loss caused by vehicle involved in crashes as well as various factors influencing on it were analyzed,the corresponding mi- cro-econometrics model was theoretically given.Moreover,the practicability of the model, the veracity and rationality of quantification were analyzed.Based on probability theory and mathematical statistical theory,macro approach to evaluating vehicle damage in crashes was presented,and the corresponding macro-econometrics model was con- structed.In addition,the macro-econometrics model was utilized to assess economic loss from statistical data of vehicle damaged in crashes,which has shown that the model can meet the demand of quantification analysis of vehicle damage,and be applied to the evaluation of economic loss caused by crashes.The results in this paper will be of practic- al significance for scientific,comprehensive and rational evaluating socio-economic loss caused by road crashes.展开更多
Though the bumper of a vehicle plays a major role in protecting the vehicle body against damage in low speed impacts, many bumpers, particularly in large vehicles, are too stiff for pedestrian protection. In designing...Though the bumper of a vehicle plays a major role in protecting the vehicle body against damage in low speed impacts, many bumpers, particularly in large vehicles, are too stiff for pedestrian protection. In designing a bumper for an automobile, pedestrian protection is as important as bumper energy absorption in low speed collisions. To prevent lower extremity injuries in car-pedestrian collisions, it is important to determine the loadings that car front structures impart on the lower extremities and the mechanisms by which injury is caused by these loadings. The present work was focused on gaining more insight into the injury mechanisms leading to both ligament damage and bone fracture during bumper-pedestrian collisions. The European Enhanced Vehicle-safety Committee （EEVC） legform impactor model was introduced and validated against EEVCAVG17 criteria. The collision mechanism between a bumper and this legform impactor was investigated numerically using LS-DYNA software. To identify the effect of the bumper beam material on leg injuries, four analyses were performed on bumpers that had the same assembly but were made from different materials.展开更多
Objective： To explore the relationship between the collision parameters of vehicle and the pedestrian thorax injury by establishing the chest simulation models in car-pedestrian collision at different velocities and ...Objective： To explore the relationship between the collision parameters of vehicle and the pedestrian thorax injury by establishing the chest simulation models in car-pedestrian collision at different velocities and angles. Methods： 87 cases of vehicle-to-pedestrian accidents, with detailed injury information and determined vehicle impact parameters, were included. The severity of injury was scaled in line with the Abbreviated Injury Scale （AIS）. The chest biomechanical response parameters and change characteristics were obtained by using Hyperworks and LS-DYNA computing. Simulation analysis was applied to compare the characteristics of injuries. Results： When impact velocities at 25, 40 and 55 km/h, respectively, 1） the maximum values of thorax velocity criterion （VC） were for 0.29, 0.83 and 2.58 m/s; and at the same collision velocity, the thorax VC from the impact on pedestrian＇s front was successively greater than on his back and on his side; 2） the maximum values of peak stress on ribs were 154,177 and 209 MPa; and at the same velocity, peak stress values on ribs from the impact on pedestrian＇s side were greater than on his front and his back. Conclusion： There is a positive correlation between the severity and risk of thorax injury and the collision velocity and angle of car-thorax crashes. At the same velocity, it is of greater damage risk when the soft tissue of thorax under a front impact; and there is also a greater risk of ribs fracture under a side impact of the thorax. This result is of vital significance for diagnosis and protection of thorax collision injuries.展开更多
文摘Background: The authors performed a computerized search of the National Pediatric Trauma Registry for all patients who had compartment syndrome during a 51-month period. Methods: One hundred thirty-three cases were identified. Boys outnumbered girls 4 to 1. The median age was 12 years and the peak incidence was in the 10-to 14-year-old age group. Results: The most common mechanisms of injury were pedestrians struck by motor vehicles, falls, sports, and occupants in motor vehicle crashes. Eighty-five percent of the cases were the sequelae of fractures. Forearm fractures were the most common cause in the upper extremity, and tibia and/or fibula fractures were most common in the lower extremity. Conclusions: Open fractures significantly increased the risk of developing a compartment syndrome for both forearm and leg fractures. Sixty percent of the patients went directly from the emergency room to the operating room, suggesting that the others developed the compartment syndrome after admission, or had delayed diagnosis.
基金Communications Bureau of Shandong Province(2005R17)
文摘Based on economics theory,social value loss caused by vehicle involved in crashes as well as various factors influencing on it were analyzed,the corresponding mi- cro-econometrics model was theoretically given.Moreover,the practicability of the model, the veracity and rationality of quantification were analyzed.Based on probability theory and mathematical statistical theory,macro approach to evaluating vehicle damage in crashes was presented,and the corresponding macro-econometrics model was con- structed.In addition,the macro-econometrics model was utilized to assess economic loss from statistical data of vehicle damaged in crashes,which has shown that the model can meet the demand of quantification analysis of vehicle damage,and be applied to the evaluation of economic loss caused by crashes.The results in this paper will be of practic- al significance for scientific,comprehensive and rational evaluating socio-economic loss caused by road crashes.
文摘Though the bumper of a vehicle plays a major role in protecting the vehicle body against damage in low speed impacts, many bumpers, particularly in large vehicles, are too stiff for pedestrian protection. In designing a bumper for an automobile, pedestrian protection is as important as bumper energy absorption in low speed collisions. To prevent lower extremity injuries in car-pedestrian collisions, it is important to determine the loadings that car front structures impart on the lower extremities and the mechanisms by which injury is caused by these loadings. The present work was focused on gaining more insight into the injury mechanisms leading to both ligament damage and bone fracture during bumper-pedestrian collisions. The European Enhanced Vehicle-safety Committee （EEVC） legform impactor model was introduced and validated against EEVCAVG17 criteria. The collision mechanism between a bumper and this legform impactor was investigated numerically using LS-DYNA software. To identify the effect of the bumper beam material on leg injuries, four analyses were performed on bumpers that had the same assembly but were made from different materials.
基金The Natural Science Foundation of China （Project number 31271006）, the Chongqing Natural Science Fund （Project number CSTC2012JJYS0004）.
文摘Objective： To explore the relationship between the collision parameters of vehicle and the pedestrian thorax injury by establishing the chest simulation models in car-pedestrian collision at different velocities and angles. Methods： 87 cases of vehicle-to-pedestrian accidents, with detailed injury information and determined vehicle impact parameters, were included. The severity of injury was scaled in line with the Abbreviated Injury Scale （AIS）. The chest biomechanical response parameters and change characteristics were obtained by using Hyperworks and LS-DYNA computing. Simulation analysis was applied to compare the characteristics of injuries. Results： When impact velocities at 25, 40 and 55 km/h, respectively, 1） the maximum values of thorax velocity criterion （VC） were for 0.29, 0.83 and 2.58 m/s; and at the same collision velocity, the thorax VC from the impact on pedestrian＇s front was successively greater than on his back and on his side; 2） the maximum values of peak stress on ribs were 154,177 and 209 MPa; and at the same velocity, peak stress values on ribs from the impact on pedestrian＇s side were greater than on his front and his back. Conclusion： There is a positive correlation between the severity and risk of thorax injury and the collision velocity and angle of car-thorax crashes. At the same velocity, it is of greater damage risk when the soft tissue of thorax under a front impact; and there is also a greater risk of ribs fracture under a side impact of the thorax. This result is of vital significance for diagnosis and protection of thorax collision injuries.
