Abdominal injuries, along with lumbar spine fractures, are part of a constellation of injuries referred to as "seat belt syndrome". Geometrical characteristics of the pelvis and abdomen of younger children place them at higher risk for these injuries. Efforts to design restraints that mitigate these injuries are limited as no current pediatric anthropomorphic dummy (ATD) can accurately quantify the abdominal response to belt loading. This paper describes progress on a four-phase project to address this gap involving pediatric anthropometrics, real-world abdominal injury risk, abdominal biomechanical structural response and injury tolerance from a porcine model, and development of an abdominal insert for the 6-year-old ATD based on these data.
Internal anthropometric measures consisted of radiological assessment of abdominal depth, height, and circumference at multiple horizontal planes. External measures consisted of distances, determined by digital photography, taken between skeletal markers while the child was seated on a vehicle seating apparatus with and without a booster seat.
Field investigation identified three unique kinematic patterns resulting in abdominal injury: presubmarining where the belt is initially out of position, classic submarining where the belt starts in position and the pelvis moves under the belt with the torso reclined, and submarining/jackknifing where the pelvis slides under the belt, and the torso flexes forward.
The biomechanical studies developed age- and size-based correlations between pediatric swine and humans. Biomechanical tests performed using the most appropriately sized porcine model will be used to define the structural and injury response of the pediatric abdomen to realistic loading conditions.