Investigation of motorcyclist safety systems contributions to prevent cervical spine injuries using HUMOS model

To prevent motorcyclists' cervical spine injuries, many passive safety devices, commonly named neck braces, are available. This work aimed to promote a methodology to investigate how injury mechanisms or injury severity involved with cervical spine safety devices could be modified or avoided. Multidirectional head impact conditions were simulated on the head-neck-thorax isolated segment by testing three different neck brace technologies and a reference simulation without any protection. The tested devices did not show signfincant changes regarding the whole neck kinematics. The interactions with thorax or helmet component were an important issue for safety system capability to control joint kinematics. Rigid or semi hard neck braces' efficiency was observed with the shift of upper cervical spine injuries to the mean cervical spine injuries location. On the other hand, the lower cervical spine injury risk was not significantly modified. The soft device tested did not show any efficiency by comparison to the reference simulations.