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The aging population is a growing concern as the increased fragility and frailty of the elderly results in an elevated incidence of injury as well as an increased risk of mortality and morbidity. To assess elderly injury risk, age-specific computational models can be developed to directly calculate biomechanical metrics for injury. The first objective was to develop an older occupant Global Human Body Models Consortium (GHBMC) average male model (M50) representative of a 65 year old (YO) and to perform regional validation tests to investigate predicted fractures and injury severity with age. Development of the GHBMC M50 65 YO model involved implementing geometric, cortical thickness, and material property changes with age. Regional validation tests included a chest impact, a lateral impact, a shoulder impact, a thoracoabdominal impact, an abdominal bar impact, a pelvic impact, and a lateral sled test.

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.

The purpose of this study was to develop injury risk functions for dynamic bending of the human femur in the lateral-to-medial and posterior-to-anterior loading directions. A total of 45 experiments were performed on human cadaver femurs using a dynamic three-point drop test setup. An impactor of 9.8 kg was dropped from 2.2 m for an impact velocity of 5 m/s. Five-axis load cells measured the impactor and support loads, while an in situ strain gage measured the failure strain and subsequent strain rate. All 45 tests resulted in mid-shaft femur fractures with comminuted wedge and oblique fractures as the most common fracture patterns. In the lateral-to-medial bending tests the reaction loads were 4180 ± 764 N, and the impactor loads were 4780 ± 792 N. In the posterior-to-anterior bending tests the reaction loads were 3780 ± 930 N, and the impactor loads were 4310 ± 1040 N. The difference between the sum of the reaction forces and the applied load is due to inertial effects.