  In the real world, the severity of traumatic injuries are measured using the
Abbreviated Injury Scale (AIS). However the AIS scale cannot currently be
computed by using finite element human computer models, which calculate a
maximum principal strains (MPS). Further, MPS only establishes a threshold
above which a serious or fatal injury occurs. In order to overcome these
limitations, a unique Organ Trauma Model (OTM) able to calculate the threat to
life of any organ injury is proposed. The focus, in this case is on real world
pedestrian brain injuries. The OTM uses a power method, named Peak Virtual
Power (PVP), and defines brain white and grey matters trauma responses as a
function of impact location and impact speed extracted from the pedestrian
collision kinematics. This research has included ageing in the injury severity
computation by including soft tissue material degradation, as well as brain
volume changes. Further, to account for the limitations of the Lagrangian
formulation of the brain model in representing haemorrhage, an approach to
include the effects of subdural hematoma is proposed and included as part of
the OTM predictions in this study. The OTM model was tested against three
real-life pedestrian accidents and has proven to reasonably predict the Post
Mortem (PM) outcome. Its AIS predictions are closer to the real world injury
severity than standard MPS methods currently recommended. This study suggests
that the OTM has the potential to improve forensic predictions as well as
contribute to the improvement in vehicle safety design through the ability to
measure injury severity. This study concludes that future advances in trauma
computing would require the development of a brain model which could predict
haemorrhaging.
