title: A multi-body dynamics study on a weight-drop test of rat brain injury.
abstract: Traumatic brain injury (TBI), induced by impact of an object with the head, is a major health problem worldwide. Rats are a well-established animal analogue for study of TBI and the weight-drop impact-acceleration (WDIA) method is a well-established model in rats for creating diffuse TBI, the most common form of TBI seen in humans. However, little is known of the biomechanics of the WDIA method and, to address this, we have developed a four-degrees-of-freedom multi-body mass-spring-damper model for the WDIA test in rats. An analytical expression of the maximum skull acceleration, one of the important head injury predictor, was derived and it shows that the maximum skull acceleration is proportional to the impact velocity but independent of the impactor mass. Furthermore, a dimensional analysis disclosed that the maximum force on the brain and maximum relative displacement between brain and skull are also linearly proportional to impact velocity. Additionally, the effects of the impactor mass were examined through a parametric study from the developed multi-body dynamics model. It was found that increasing impactor mass increased these two brain injury predictors.
authors.affiliation: a Department of Mechanical & Aerospace Engineering , Monash University , Clayton , Australia.
authors.forename: Wenyi
authors.initials: W
authors.lastname: Yan
authors.affiliation: b École Nationale Supérieure de Mécanique et d'Aérotechnique , Futuroscope Chasseneuil Cedex , France.
authors.forename: Germain
authors.initials: G
authors.lastname: Sossou
authors.affiliation: c Department of Physiology , Monash University , Clayton , Australia.
authors.forename: Ramesh
authors.initials: R
authors.lastname: Rajan
mesh_terms: D000054:Acceleration; D000818:Animals; D001696:Biomechanical Phenomena; D001835:Body Weight; D001921:Brain / Q000503:physiopathology; D001930:Brain Injuries / Q000503:physiopathology*; D004195:Disease Models, Animal; D006801:Humans; D008962:Models, Theoretical; D009716:Numerical Analysis, Computer-Assisted; D051381:Rats; D012886:Skull / Q000503:physiopathology
keywords: Traumatic brain injury; multi-body dynamics; rat brain injury model