Publications by authors named "Ryusuke Asahi"

The aims of this study were as follows: the (a) creation of a pregnant occupant finite element model based on pregnant uterine data from sonography, (b) development of the evaluation method for placental abruption using this model and (c) analysis of the effects of three factors (collision speed, seatbelt position and placental position) on the severity of placental abruption in simulations of vehicle collisions. The 30-week pregnant occupant model was developed with the uterine model including the placenta, uterine-placental interface, fetus, amniotic fluid and surrounding ligaments. A method for evaluating the severity of placental abruption on this pregnant model was established, and the effects of these factors on the severity of the injury were analyzed.

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The characteristic subcutaneous hemorrhage along the seat belt in motor vehicle accidents is called the seat belt sign (SBS). The risk of organ injuries is especially high when abdominal SBS is located above the anterior superior iliac spine (ASIS). The purpose of this study analyzed the physical and radiographic factors of healthy volunteers sit on car seat that affect initial position of abdominal seat belt, namely "lap belt", related to the seat belt injury.

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Article Synopsis
  • Human body model analysis was conducted to evaluate how lumbar and pelvic angles affect the effectiveness of seat belts in reducing injuries from accidents, but no previous relationships were established.
  • The study measured lumbar lordosis (LL) and pelvic angle (PA) in 75 individuals, leading to the creation of a Total Human Model for Safety which underwent simulations under crash test conditions.
  • Results indicated that increasing lumbar lordosis and decreasing pelvic angle improved seat belt positioning, potentially enhancing passenger safety by reducing injury risks during frontal impacts.
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Article Synopsis
  • The study investigates how global spine alignment changes when individuals sit in car seats, as there has been limited research on this topic.
  • It involves a sample of 113 healthy adults and uses radiographic measurements to analyze different spine alignment angles in both standing and sitting positions.
  • Results show that transitioning from standing to sitting generally decreases cervical lordosis and thoracic kyphosis while slightly increasing thoracolumbar kyphosis.
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