The main task of the thesis’s work was performing a simulation of a shaking episode to analyse the phenomenon of Abusive Head Trauma (AHT). This was done using a finite element model, the PIPER Child Model, that replicates an 18-months-old baby.
The simulations gave many outputs that can be seen thanks to LS-PrePost. The ones analysed deeply regarded especially velocities and accelerations of the head. What resulted was a stabilized trend after a certain time, also if some curves were different from the ones expected (after having considered several literature’s articles). In particular, the displacement of the head did not replicate a backward-forward movement and probably this is due to the weight of the head. Moreover, the comparison with other child models was for sure a critical point, because of the little amount of data (in particular about trends) found in literature papers. Nevertheless, a comparison with some child models was made, verifying that usually models with similar weights and with similar boundary conditions register comparable maxima values of the kinematic parameters.
For what concerns the injury damages’ estimation, what comes from this study was that the reached values of accelerations and velocities are below the thresholds established by some medical and biomechanical works. This should suggest that the Abusive Head Trauma is not normally the first cause of diffuse axonal injury or subdural hematomas, at least if no impacts against any surface are present. Despite this, obviously shaking an infant is potentially dangerous and unsafe, as the evidence of many real cases state. In addition, for what regards the finite element simulation, these results are strictly related with the condition given in terms of shaking law (amplitude and phase), total mass of the body, head’s weight and complexity of the model used. It is reasonable to think that different results can come out changing these conditions or introducing an impact, remembering that about it much more articles and researches have been done in literature’s work.
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