Forman Jason L, Segui-Gomez Maria, Ash Joseph H, Lopez-Valdes Francisco J
European Center for Injury Prevention, Universidad de Navarra University of Virginia, Center for Applied Biomechanics.
Ann Adv Automot Med. 2011;55:3-14.
Understanding pediatric occupant postures can help researchers indentify injury risk factors, and provide information for prospective injury prediction. This study sought to observe lateral head positions and shoulder belt fit among older child automobile occupants during a scenario likely to result in sleeping - extended travel during the night. An observational, volunteer, in-transit study was performed with 30 pediatric rear-seat passengers, ages 7 to 14. Each was restrained by a three-point seatbelt and was driven for seventy-five minutes at night. Ten subjects used a high-back booster seat, ten used a low-back booster seat, and ten used none (based on the subject height and weight). The subjects were recorded with a low-light video camera, and one frame was analyzed per each minute of video. The high-back booster group exhibited a statistically significant (p<0.05) decrease in the mean frequency of poor shoulder belt fit compared to the no-booster and low-back booster groups. The high-back booster group also exhibited statistically significant decreases in the 90(th) percentile of the absolute value of the relative lateral motion of the head. The low-back booster group did not result in statistically significant decreases in poor shoulder belt fit or lateral head motion compared to the no-booster group. These results are consistent with the presence of large lateral supports of the high-back booster which provided support to the head while sleeping, reducing voluntary lateral occupant motion and improving shoulder belt fit. Future work includes examining lap belt fit in-transit, and examining the effects of these observations on predicted injury risk.
了解儿童乘车姿势有助于研究人员识别损伤风险因素，并为前瞻性损伤预测提供信息。本研究旨在观察大龄儿童汽车乘客在夜间可能导致睡眠——长途旅行的场景中的头部侧向位置和肩带贴合情况。对30名7至14岁的儿科后排乘客进行了一项观察性、自愿性的车内研究。每名乘客均使用三点式安全带约束，并在夜间行驶75分钟。10名受试者使用高靠背增高座椅，10名使用低靠背增高座椅，10名未使用（根据受试者身高和体重）。用低光照摄像机记录受试者情况，每分钟视频分析一帧。与未使用增高座椅组和低靠背增高座椅组相比，高靠背增高座椅组肩带贴合不佳的平均频率出现了具有统计学意义的降低（p<0.05）。高靠背增高座椅组头部相对侧向运动绝对值的第90百分位数也出现了具有统计学意义的降低。与未使用增高座椅组相比，低靠背增高座椅组在肩带贴合不佳或头部侧向运动方面未出现具有统计学意义的降低。这些结果与高靠背增高座椅存在较大侧向支撑相符，该支撑在睡眠时为头部提供支撑，减少乘客的自主侧向运动并改善肩带贴合情况。未来的工作包括检查乘车时腰部安全带的贴合情况，以及研究这些观察结果对预测损伤风险的影响。
