Computational studies of ‘whiplashg’ injuries

Abstract

The term 'whiplash' was initially used to describe injuries to the neck caused by the head being forced backwards during a rear-end collision in cars without head restraints. The addition of head restraints in the 1970s was expected to solve this problem by preventing excessive extension of the neck but experience suggests the problem still exists. This paper reviews available experimental studies of whiplash and uses the data to construct a finite element model which is capable of dynamically simulating whiplash collisions and predicting the forces in all the relevant neck ligaments. For the first time, it is shown that trauma occurs long before the head hits the head restraint as a result of displacement between the head and the torso caused by the head's inertia leading to markedly different acceleration histories. It is concluded that experimental and computational studies must be used together to produce progress in biomechanical studies.

Using a Finite Element Model to Evaluate Human Injuries Application to the HUMOS Model in Whiplash Situation

“…It is especially in agreement with the work of Gentle et al, 30 Panjabi et al, 49 Kaneoka et al, 50 and Grauer et al, 48 who also described the S-shaped curvature of the spine in the early phase of whiplash and the biphasic motion of the upper cervical spine (Figure 9). This Sshape curvature effect seems to be related to the head inertia.…”

“…They stated that as the elastic modulus was increased, the head angle and angular acceleration increased. Gentle et al 30 reproduced the experimental arrangement of posterior impact for an adult, sitting in a normal seating position, but the topologic information of the skull and the cervical vertebrae was extracted from full-color pictures obtained by the Visible Human Project. 31 They concluded that the evaluation of their model has shown it to be successful in terms of predicting the rotation displacement and acceleration history of the head in the sagittal plane in comparison with experimental data.…”

The rate of change of acceleration: Implications to head kinematics during rear-end impacts

“…Many whiplash studies have focused on the change in velocity to characterize the experiment and consequently act as a determining factor for predicting injury at higher perturbation levels (Brault et al, 2000;Castro et al, 1997;Gentle et al, 2001;Severy et al, 1955;Siegmund et al, 2004Siegmund et al, , 2005b, while others have used peak acceleration (Blouin et al, 2003b;Cholewicki et al, 1998;Luan et al, 2000;Millington et al, 2005;Siegmund et al, 2005a). Linder et al (2003) observed a wide variation in mean acceleration for a specified change in velocity in both laboratory and real-world crash data.…”

An investigation into neck injuries in simulated frontal impacts

“…Therefore, there has been great emphasis on computational simulation. 46–55 FE models need a great deal of computational power, but can provide detailed information about tissue deformations and injury prediction. Multibody models can also include many anatomical details while being computationally efficient.…”