Validating a Device for Whiplash Motion Simulation in a Porcine Model

Whiplash injury is a common outcome following minor automobile collisions. One theorizedmechanism for whiplash injury is that the rapid head and neck motions induced by a collision caninjure nerve cells in the dorsal root ganglia through pressure gradients developed in the spinalcanal and surrounding tissues. This injury mechanism has previously been studied in humancadaver and porcine models. However, the whiplash motion simulation methods in the latterstudies lacked the control necessary to explore the independent effects of head rotation andretraction on the measured spinal pressures. This project aimed to address the limitations ofprevious porcine whiplash studies by developing and validating a new whiplash motion simulationdevice to enable further study of this injury mechanism. The new proposed device consists of twoservomotors which can be programmed to precisely actuate a headplate through mechanicallinkages. For the current study, an inert surrogate model was used for preliminary testing of thedevice using a whiplash motion profile from previous porcine studies. The time scale of the motionprofile was adjusted to incrementally increase severity. The positional accuracy and repeatabilityof the device was assessed through marker tracking of the headplate and logging of the motorencoder positions. Angular rates and linear accelerations of the plate were also measured. Testingdemonstrated the strengths of the proposed device in accurately and repeatably replicatingprogrammed motion profiles. Some design modifications can potentially enable simulatingwhiplash motion severities commensurate with previous porcine whiplash studies. With futuretesting using this device, our understanding of the pressure-induced whiplash injury mechanismcan be improved, which can inform effective treatments and preventative measures for whiplashinjury

The Lack of Sex, Age, and Anthropometric Diversity in Neck Biomechanical Data

Female, elderly, and obese individuals are at greater risk than male, young, and non-obese individuals for neck injury in otherwise equivalent automotive collisions. The development of effective safety technologies to protect all occupants requires high quality data from a range of biomechanical test subjects representative of the population at risk. Here we sought to quantify the demographic characteristics of the volunteers and post-mortem human subjects (PMHSs) used to create the available biomechanical data for the human neck during automotive impacts. A systematic literature and database search was conducted to identify kinematic data that could be used to characterize the neck response to inertial loading or direct head/body impacts. We compiled the sex, age, height, weight, and body mass index (BMI) for 999 volunteers and 110 PMHSs exposed to 5,431 impacts extracted from 63 published studies and three databases, and then compared the distributions of these parameters to reference data drawn from the neck-injured, fatally-injured, and general populations. We found that the neck biomechanical data were biased toward males, the volunteer data were younger, and the PMHS data were older than the reference populations. Other smaller biases were also noted, particularly within female distributions, in the height, weight, and BMI distributions relative to the neck-injured populations. It is vital to increase the diversity of volunteer and cadaveric test subjects in future studies in order to fill the gaps in the current neck biomechanical data. This increased diversity will provide critical data to address existing inequities in automotive and other safety technologies.</jats:p