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A blast buck (Accelerative Loading Fixture, or ALF) was developed for studying underbody blast events in a laboratory-like setting. It was designed to provide a high-magnitude, high-rate, vertical loading environment for cadaver and dummy testing. It consists of a platform with a reinforcing cage that supports adjustable-height rigid seats for two crew positions. The platform has a heavy frame with a deformable floor insert. Fourteen tests were conducted using fourteen PMHS (post mortem human surrogates) and the Hybrid III ATD (Anthropomorphic Test Device). Tests were conducted at two charge levels: enhanced and mild. The surrogates were tested with and without PPE (Personal Protective Equipment), and in two different postures: nominal (knee angle of 90°) and obtuse (knee angle of 120°). The ALF reproduces damage in the PMHS commensurate with injuries experienced in theater, with the most common damage being to the pelvis and ankle.

Carotid artery injury due to motor vehicle crash has been attributed to direct impact to the neck and stretching of the artery. This study examines the response of a finite element model of the neck and carotid arteries given a farside vehicle impact. This regional carotid artery model was developed using existing material properties and based on a spine model developed by NHTSA. The finite element model was subjected to loading conditions derived from farside PMHS tests conducted at Medical College of Wisconsin. The PMHS tests represented four inboard belt loading conditions of the neck. The belts were located high on the neck, for maximal compression of the vessel, or low on the neck, for maximal excursion of the head. There was a low speed and a high speed test for each of the belt configurations. These boundary conditions were implemented in the model and the response of the carotid was quantified using strain measurements.

Injuries caused by motor vehicle crashes (MVCs) are the leading cause of head injury and death for children in the United States. This study aims to describe the shape and size (morphologic) changes of the cerebrum, cerebellum, brainstem, and ventricles of the pediatric occupant to better predict injury and assess how these changes affect finite element model (FEM) response. To quantify morphologic differences in the brain, a Generalized Procrustes Analysis (GPA) with a sliding landmark method was conducted to isolate morphologic changes using magnetic resonance images of 63 normal subjects. This type of geometric morphometric analysis was selected for its ability to identify homologous landmarks on structures with few true landmarks and isolate the shape and size of the individuals studied. From the resulting landmark coordinates, the shape and size changes were regressed against age to develop a model describing morphologic changes in the pediatric brain as a function of age.

More brain structure specific scaling factors are needed to create more accurate models of the pediatric population for injury prevention research. This study examines the internal structure of the brain using the common imaging modality of magnetic resonance imaging to collect data on subjects ranging in age from newborn to 21 years old. This data set was then analyzed using geometric morphometrics to quantify the shape change of the measured structures. From this analysis geometric scaling factors for each structure were determined. The accuracy of parametric models of the head will be improved by using these structure specific scaling factors.