Detection of bridging veins rupture and subdural haematoma onset using a finite element head model.

BACKGROUND: One of the most severe traumatic brain injuries, the subdural haematoma, is related to damage and rupture of the bridging veins, generating an abnormal collection of blood between the dura mater and arachnoid mater. Current numerical models of these vessels rely on very simple geometries and material laws, limiting its accuracy and bio-fidelity. METHODS: In this work, departing from an existing human head numerical model, a realistic geometry for the bridging veins was developed, devoting special attention to the finite elements type employed. A novel and adequate constitutive model including damage behavior was also successfully implemented. FINDINGS: Results attest that vessel tearing onset was correctly captured, after comparison against experiments on cadavers. INTERPRETATION: Doing so, the model allow to precisely predict the individual influence of kinematic parameters such as the pulse duration, linear and rotational accelerations in promoting vessel tearing.

Motorcycle helmets--a state of the art review.

This paper tries to make an overview of the work carried out by scientific community in the area of road helmets safety. In an area that is constantly being pushed forward by market competition, self-awareness of danger and tighter standards, several research groups around the world have contributed to safety gear improvement. In this work concepts related to head impact protection and energy absorption are explained. It also makes reference to the theories related to the development of helmets, as well as to the different existing types nowadays. The materials that are typically used in impact situations and new design concepts are also approached. In addition, it is presented a literature review of current--and most commonly used--helmet test standards, along with new tests and helmet concepts to assess the effects of rotational motion. In a non-restrictive, and never up-to-date report, a state-of-art review on road helmets safety is done, with a special insight into brain injury, helmet design and standards.