John Humm1, Narayan Yoganandan1. 1. Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin.
Abstract
OBJECTIVE: The study's aim is to examine which sternum deflection measure best represents injury in oblique frontal impacts with small female surrogates. METHODS: Data from sixteen PMHS sled tests were used to calculate sternum deflection using displacements in the A-P (x) direction, transverse (xy) plane, sagittal (xz) plane, and triplanar (xyz). Peak deflections were the response variable and were combined with injury outcomes to generate injury risk curves (IRCs) using parametric statistical survival modeling. The IRC with the lowest Brier Score Metric was considered the best deflection measure representing injury. RESULTS: The triplanar (xyz) deflection metric was the best indicator of injury. At the 10 and 50% probability levels, the magnitudes of this metric were 33 mm and 55 mm, respectively. The quality of the risk curve was fair for 10% and good for 50%, based on the ISO recommendations. CONCLUSIONS: The current study reports on the injury risk to small females in an upright seated position in oblique frontal impacts. The triplanar and transverse plane deflection metrics were similar for this posture; however, occupants in reclined configurations may demonstrate a different response, and further investigations are necessary.
OBJECTIVE: The study's aim is to examine which sternum deflection measure best represents injury in oblique frontal impacts with small female surrogates. METHODS: Data from sixteen PMHS sled tests were used to calculate sternum deflection using displacements in the A-P (x) direction, transverse (xy) plane, sagittal (xz) plane, and triplanar (xyz). Peak deflections were the response variable and were combined with injury outcomes to generate injury risk curves (IRCs) using parametric statistical survival modeling. The IRC with the lowest Brier Score Metric was considered the best deflection measure representing injury. RESULTS: The triplanar (xyz) deflection metric was the best indicator of injury. At the 10 and 50% probability levels, the magnitudes of this metric were 33 mm and 55 mm, respectively. The quality of the risk curve was fair for 10% and good for 50%, based on the ISO recommendations. CONCLUSIONS: The current study reports on the injury risk to small females in an upright seated position in oblique frontal impacts. The triplanar and transverse plane deflection metrics were similar for this posture; however, occupants in reclined configurations may demonstrate a different response, and further investigations are necessary.