Eric Wagnac

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Despite an increase in the number of experimental and numerical studies dedicated to spinal trauma, the influence of the rate of loading or displacement on lumbar spine injuries remains unclear. In the present work, we developed a bio-realistic finite element model (FEM) of the lumbar spine using a comprehensive geometrical representation of spinal(More)
Finite element models (FEM) dedicated to vertebral fracture simulations rarely take into account the rate dependency of the bone material properties due to limited available data. This study aims to calibrate the mechanical properties of a vertebral body FEM using an inverse method based on experiments performed at slow and fast dynamic loading conditions.(More)
Sudden deceleration and frontal/rear impact configurations involve rapid movements that can cause spinal injuries. This study aimed to investigate the rotation rate effect on the L2-L3 motion segment load-sharing and to identify which spinal structure is at risk of failure and at what rotation velocity the failure may initiate? Five degrees of sagittal(More)
Under fast dynamic loading conditions (e.g. high-energy impact), the load rate dependency of the intervertebral disc (IVD) material properties may play a crucial role in the biomechanics of spinal trauma. However, most finite element models (FEM) of dynamic spinal trauma uses material properties derived from quasi-static experiments, thus neglecting this(More)
Thoracolumbar spine fracture classifications are mainly based on a post-traumatic observation of fracture patterns, which is not sufficient to provide a full understanding of spinal fracture mechanisms. This study aimed to biomechanically analyze known fracture patterns and to study how they relate to fracture mechanisms. The instigation of each fracture(More)
In spinal instrumentation surgery, the optimal placement of pedicle screws that takes into account the cortical/cancellous bone quality, geometry and property distribution, and screw design is still undetermined despite several in vitro experiments. The objective of this study was to evaluate the feasibility of using a detailed finite element model (FEM) of(More)
STUDY DESIGN Detailed biomechanical analysis of the anchorage performance provided by different pedicle screw designs and placement strategies under pullout loading. OBJECTIVE To biomechanically characterize the specific effects of surgeon-specific pedicle screw design parameters on anchorage performance using a finite element model. SUMMARY OF(More)
Finite element (FE) models are very efficient tools to study internal stresses in human structures that induce severe pressure sores. Unfortunately, methods currently used to generate FE models are not suitable for clinical application involving wheelchair users. A clinical-oriented method, based on calibrated-biplanar radiographs, was therefore developed(More)
STUDY DESIGN An experimental study of pedicle screw fixation in human cadaveric vertebrae. OBJECTIVE The aim of this study was to experimentally characterize pedicle screw fixation under nonaxial loading and to analyze the effect of the surgeons' screw and placement choices on the fixation risk of failure. SUMMARY OF BACKGROUND DATA Pedicle screw(More)