A Three-Dimensional Model of the Human Cervical Spine for Impact Simulation

Abstract

A three-dimensional analytical model of the cervical spine is described. The cervical vertebrae and the head are modeled as rigid bodies which are interconnected by deformable elements representing the intervertebral disks, facet joints, ligaments and muscles. A special pentahedral continuum element for representing the articular facets is described which effectively maintains stability of the cervical spine in both lateral and frontal plane accelerations, which is very difficult with multi-spring models of the facets. A simplified representation is used for the spine and body below the level of T1. The neck musculature is modeled by over 100 muscle elements representing 22 major muscle groups in the neck. The model has been validated for frontal and sideways impact accelerations by simulating published experimental data. Results are also presented to show the effects of the stretch reflex response on the dynamics of the head and neck under moderate acceleration.

Numerical Analysis of Three-Dimensional Cervical Behaviors in Posterior-Oblique Car Collisions Using 3-D Human Whole Body Finite Element Model

“…Williams and Belytshko reported the head response using a threedimensional mathematical model with rigid bodies and beam elements (29) . Linder reported on the forces acting on the cervical spine using a newly-developed rigid-body model of a 50th-percentile human (31) .…”

“…Over the past decades, in many biomechanical studies, cervical behaviors have been evaluated to reveal the mechanism of whiplash injuries using experimental and numerical analyses (29) - (31) solely on the twodimensional sagittal plane of the cervical spine. Williams and Belytshko reported the head response using a threedimensional mathematical model with rigid bodies and beam elements (29) .…”

Application of the MEBDFV solver to dynamic simulation of some specific multibody systems: an example of a cervical spine model

“…Dauvillers et al [30], in turn, modeled the ligaments as linearly elastic elements with damping and used identical stiffness constant for all of them. Some authors proposed nonlinear models [39][40][41]. Due to common use of the finite element method in numerical simulations, shell and beam models [33] as well as the spring and axial (link) ones [42] have become popular.…”

“…In problems related to cervical spine biomechanics, solid models are widely applied. It is assumed that a disc is a homogenuous elastic body with known Young's modulus and Poisson's ratio [38,39,43]. In order to take into account the acting loads, the discs were divided into three parts: annulus, annulus fibrosus and nucleus pulposus.…”

A Three-Dimensional Head-Neck Model: Validation for Frontal and Lateral Impacts

“…In finite element models of the neck, as developed by Williams and Belytschko [18] and recently by Kleinberger [19], a highly detailed representation of cervical spine geometry and material behaviour may be employed. These models are complex and have many parameters, which makes them computationally less efficient and more difficult to validate than discrete parameter models.…”