Biomechanics of Lumbar Spine Injury in Road Barrier Collision–Finite Element Study

Abstract

Literature and field data from CIREN database have shown that lumbar spine injuries occur during car crashes. There are multiple hypotheses regarding how they occur; however, there is no biomechanical explanation for these injuries during collisions with road safety barriers (RSBs). Therefore, the objective of this study was to investigate the mechanics of vertebral fractures during car collisions with concrete RSBs. The finite element method was used for the numerical simulations. The global model of the car collision with the concrete RSB was created. The lumbar spine kinematics were extracted from the global simulation and then applied as boundary conditions to the detailed lumbar spine model. The results showed that during the collision, the occupant was elevated, and then dropped during the vehicle landing. This resulted in axial compression forces 2.6 kN with flexion bending moments 34.7 and 37.8 Nm in the L2 and L3 vertebrae. It was shown that the bending moment is the result of the longitudinal force on the eccentricity. The lumbar spine index for the L1–L5 section was 2.80, thus indicating a lumbar spine fracture. The minimum principal strain criterion of 7.4% and damage variable indicated L2 and L3 vertebrae and the inferior part of L1, as those potentially prone to fracture. This study found that lumbar spine fractures could occur as a consequence of vehicle landing during a collision with a concrete RSB mostly affecting the L1–L3 lumbar spine section. The fracture was caused by a combination of axial forces and flexion bending moments.

Development and validation of lumbar spine finite element model

“…As a result, it is possible to investigate in detail deformation and the state of stresses in individual soft tissues. Numerical modeling of entire sections of the spine allows for analysis of risk injury that can occur in the human body during car accidents ( Ivancic, 2013 ; Yoganandan et al, 2013 ; Pachocki et al, 2021 ; Kaufman et al, 2013 ).…”

“…In addition, a validation of tensile forces acting in the lumbar section was performed, which is not usually conducted. However, these loading modes are frequently observed during road accidents ( Pachocki et al, 2021 ). The original contribution of the article is a separation of the NP from the surrounding bones and the AF.…”

“…In order to achieve this goal nonlinear orthotropic material model was used for ligaments and modifications were introduced to the models of intervertebral discs to better reflect their anatomical structure and properties. Material parameters were taken from the literature and calibrated with respect to experimental flexion and compression tests, as they are of key importance in the analysis of road accidents ( Richards et al, 2006 ; Ivancic, 2013 ; Pachocki et al, 2021 ; Tushak et al, 2023 ). In the present study, the set of validation tests were extended in relation the THUMS documentation ( Toyota Motor Corporation & Toyota Central R and D Labs.…”

Influence of a Lighting Column in the Working Width of a W-Beam Barrier on TB51 Crash Test

“…Those numbers show how much remains to be done in improving road safety. The key to understanding the need and building tools to manage road infrastructure to reduce the consequences of lane departure vehicle accidents is to know the actual conditions on the roads [ 3 ] and to identify the hazards and their sources that result from inadequate design, construction, installation, and maintenance of roadway vehicle restraints [ 4 , 5 , 6 , 7 ]. Roadway barriers should be considered as obstacles, and their use should be treated as a necessity [ 8 , 9 , 10 ].…”