The objective of the present paper is to provide new insight not only to an original head trauma database but also to the intra-cranial response of the human head computed with an existing head FE model under accidental circumstances. More precisely, the separate contribution of rotational acceleration and linear acceleration at the time of impact to the intra-cerebral shearing stresses and brain-skull relative motion are investigated. Moreover, the analysis is conducted separately as a function of type of accident, i.e. pedestrian, motorcyclists and sport accidents in order to analyse the effect of head rotational acceleration and to demonstrate how important it is to record both linear and angular head form acceleration under experimental head impact test and that both components should be considered for head FE model driving.