Biomechanical Data Collection Informs Latest Advances, Detailed in New Report from The Children's Hospital of Philadelphia and the Association of International Automobile Manufacturers, Inc.
A research report released today by The Children's Hospital of Philadelphia (CHOP) and the Association of International Automobile Manufacturers, Inc. (AIAM) details CHOP's cutting-edge work with academic and industry collaborators to develop more accurate child crash test dummies, called child anthropometric test devices (ATD's).
"These developments fill crucial gaps in knowledge that will allow for innovative restraint products and vehicle designs to help save more children's lives, prevent injuries, and reduce the economic cost of crashes involving child passengers," said Michael J. Stanton, president and CEO of AIAM. "We are honored to provide our support for this critical research report. Child-safety is a top priority for our member companies, and The Children's Hospital of Philadelphia has a long history of leadership on such an important issue."
Experts in pediatric biomechanics at CHOP have studied real-world crashes for more than a decade in order to understand how children's bone structure and soft tissues respond to crash forces differently than fully-developed adults. However, child crash test dummies have essentially been smaller-sized versions of adult dummies, with little consideration for these important differences in body composition -- leaving children more vulnerable to injuries during a crash than adults.
"In order for the auto industry to innovate beyond just 'buckle up' to keep kids safe in crashes, we need better tools, such as accurate child crash test dummies; but we're missing the basic data we need to create those tools," said Kristy Arbogast, Ph.D., director of engineering for CHOP's Center for Injury Research and Prevention. "The research being conducted by biomechanics research centers around the world and here at CHOP delivers the critical data on how children move in a crash and the tolerance of their bodies to injury. This information is needed to determine how cars can be made safer for children in the future."
The 2010 Child Passenger Safety Issue Report describes research conducted by CHOP and others to improve several body regions in the current child ATD to better represent an actual child's body mechanics: the head and brain, the neck and spine, the abdomen, and the thoracic region (chest and rib cage). These body regions account for the most commonly-seen -- and some of the most serious -- injuries among children involved in car crashes.
Preventing Head and Brain Injury
Brain and skull injuries are the most common type of injury among crash-involved children. Motor vehicle safety systems, including seat belts, air bags, child seats, and occupant compartment padding, are key elements for reducing injuries to the head. However, for children past toddler-age, no accurate model exists to represent a child's developing skull and brain-tissue, which respond differently to impact and crash forces than an adult's or younger child's do. To address this gap, researchers at CHOP and the University of Pennsylvania (UPenn) are working together to develop brain injury criteria for a 6- to 10-year-old child. With these criteria established, an accurate computational model can be developed that mimics the ATD currently available for this age group, to predict the likelihood of brain injury.
Using Bumper Cars to Understand the Pediatric Spine
The cervical spine controls the movement of the head during a crash, and recent research indicates that the spine used in the pediatric ATD may be significantly more rigid than an actual child's spine. Researchers at CHOP recognized the implications of this disparity and partnered with Rowan University, Takata Corporation, and the University of Virginia to devise a unique solution to quantify the motion of a typical adult's and child's spine: bumper cars.
The team measured the "crash" severity in the amusement park ride, then developed a sled test to mimic this experiment in a lab. Subjects were fitted with sensors to track the precise movements of the head, neck and spine during a safe crash force.
"We found that the children's head and spine moved further forward than the adult's, and that the youngest children experienced the most neck flexion," explained Dr. Arbogast. "This leads to more head rotation in children, making it more likely for a child's head to hit the seat, window, or something else in the car during a crash."
These findings form the basis for the development of a more accurate spine for the pediatric dummy, informing industry advancements in restraint and vehicle design to prevent injuries to the head, which remain the most common type of crash injury, and the most deadly.
Preventing "Seat Belt Syndrome"- Abdominal Injuries
Injuries to the abdominal organs are the second most common in crash-injured children, especially in those who are moved into an adult seat belt before they are 4'9" (usually around age 8.) The pediatric ATD's currently used in crash tests do not have the ability to accurately detect injuries to the abdomen.