Pierre-Jean Arnoux

Aix-Marseille Université, Marsiglia, Provence-Alpes-Côte d'Azur, France

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Publications (39)57.05 Total impact

  • Juan Henao · Carl-Éric Aubin · Hubert Labelle · Pierre-Jean Arnoux
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    ABSTRACT: Scoliosis is a 3D deformation of the spine and rib cage. For severe cases, surgery with spine instrumentation is required to restore a balanced spine curvature. This surgical procedure may represent a neurological risk for the patient, especially during corrective maneuvers. This study aimed to computationally simulate the surgical instrumentation maneuvers on a patient-specific biomechanical model of the spine and spinal cord to assess and predict potential damage to the spinal cord and spinal nerves. A detailed finite element model (FEM) of the spine and spinal cord of a healthy subject was used as reference geometry. The FEM was personalized to the geometry of the patient using a 3D biplanar radiographic reconstruction technique and 3D dual kriging. Step by step surgical instrumentation maneuvers were simulated in order to assess the neurological risk associated to each maneuver. The surgical simulation methodology implemented was divided into two parts. First, a global multi-body simulation was used to extract the 3D displacement of six vertebral landmarks, which were then introduced as boundary conditions into the personalized FEM in order to reproduce the surgical procedure. The results of the FEM simulation for two cases were compared to published values on spinal cord neurological functional threshold. The efficiency of the reported method was checked considering one patient with neurological complications detected during surgery and one control patient. This comparison study showed that the patient-specific hybrid model reproduced successfully the biomechanics of neurological injury during scoliosis correction maneuvers.
    Computer Methods in Biomechanics and Biomedical Engineering 09/2015; DOI:10.1080/10255842.2015.1075010 · 1.77 Impact Factor
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    ABSTRACT: The clinical advantages of reducing spondylolisthesis over fusion in situ have several intuitive reasons such as restore the spinal column into a more anatomic relationship and alignment. However, there is only little evidence in the literature supporting the theoretical advantages of reduction, and its effect on spinopelvic alignment remains poorly defined. In this study, a comprehensive finite element model was developed to analyze the biomechanics of the spine after spinal fusion at L5-S1 in both types of high-grade spondylolisthesis (balanced and unbalanced pelvis). The relevant clinical indices (i.e. spondylolisthesis grade and Dubousset lumbosacral angle), the displacement of L4-L5, pressure within the annulus and nucleus, and stress at L4-L5 were evaluated and compared. The model can well predict the changes of the important clinical indices during the surgery. For a balanced pelvis, the reduction has a minimal effect on the biomechanical conditions at the adjacent level during postsurgical activities. In the unbalanced case, reduction induced larger deformation in the lumbosacral region and a higher stress concentration at adjacent level. Whether such a stress concentration can lead to long-term disc degeneration is not known. The results provide additional information for the clinician considering reduction of high-grade spondylolisthesis.
    Medical & Biological Engineering 08/2015; DOI:10.1007/s11517-015-1353-0 · 1.73 Impact Factor
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    ABSTRACT: Some cardiopulmonary resuscitation (CPR) monitoring devices were released in recent years. Some of them are motion sensors. There are no guidelines were to position future or present sensors during CPR. We evaluate the possible influence of the location of motion sensors by a high-speed camera during a CPR on a manikin. We performed a motion analysis by a high-speed camera during chest compression (CC) on a manikin to quantify chest inhomogeneous displacements and rescuer motion. Midline chest was found to have an inhomogeneous depth during CC (19mm for the upper sternum, 27mm for the middle of the sternum, and 47mm for the xiphoid). Rescuer anatomy has a complex motion. The direct application of the sensor under the hand performing CC seems to be the more accurate solution if the device allows it. Copyright © 2015. Published by Elsevier Inc.
    The American journal of emergency medicine 07/2015; DOI:10.1016/j.ajem.2015.07.051 · 1.27 Impact Factor
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    ABSTRACT: This work was conducted to study biomechanical properties and macroscopic analysis of petrous fracture by lateral impact. Seven embalmed intact human cadaver heads were tested to failure using an electrohydraulic testing device. Dynamic loading was done at 2 m/s on temporal region with maximal deflection to 12 mm. Anthropometric and pathological data were determined by pretest and posttest computed tomography images, macroscopic evaluation, and anatomical dissection. Biomechanical data were obtained. Results indicated the head to have nonlinear structural response. The overall mean values of failure forces, deflections, stiffness, occipital, and frontal peak acceleration were 7.1 kN (±1.1), 9.1 mm (±1.8), 1.3 kN/mm (±0.4), 90.5 g (±22.5), and 65.4 g (±16), respectively. The seven lateral impacts caused fractures, temporal fractures in six cases. We observed very strong homogeneity for the biomechanical and pathological results between different trials in our study and between data from various experiments and our study. No statistical correlation was found between anthropometric, biomechanical, and pathological data. These data will assist in the development and validation of finite element models of head injury.
    Medical & Biological Engineering 06/2015; DOI:10.1007/s11517-015-1317-4 · 1.73 Impact Factor
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    ABSTRACT: Recently, a T2*-weighted template and probabilistic atlas of the white and gray matter (WM, GM) of the spinal cord (SC) have been reported. Such template can be used as tissue-priors for automated WM/GM segmentation but can also provide a common reference and normalized space for group studies. Here, a new template has been created (AMU40), and accuracy of automatic template-based WM/GM segmentation was quantified. The feasibility of tensor-based morphometry (TBM) for studying voxel-wise morphological differences of SC between young and elderly healthy volunteers was also investigated.
    NeuroImage 05/2015; 117. DOI:10.1016/j.neuroimage.2015.05.034 · 6.36 Impact Factor
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    ABSTRACT: Cervical myelopathy diagnosis and management in clinical practice still lacks of objective markers of potential surgery outcome. Therefore, we applied a multimodal MRI protocol, combining DTI (known to be more predictive of surgical outcome than the sole presence of T2 hyperintensity) and inhomogeneous magnetization transfer (ihMT, myelin-specific technique) to 2 patients before and 3 months after decompressive surgery. We observed both metrics evolution after surgery and neurological function evolution to see whether this multimodal protocol could help in understanding the evolutive pattern of the disease after surgery. Longitudinal follow-up until 1year post-surgery will help in answering the raised question.
    ISMRM Annual Meeting & Exhibition, Toronto, Ontario, Canada; 05/2015
  • Omar Chebil · Pierre-Jean Arnoux · Michel Behr
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    ABSTRACT: The geometric fidelity of the inner organs on finite-element model (FEM)s of the human body and the choice to use discontinuous mesh engender the appearance of empty spaces that do not reflect the real-life situation of human body cavities. The aim of this study is to assess the influence of these empty spaces on the behavior of a simplified FEM build with three different structures in interaction which properties are relevant with the abdominal cavity. This FEM is made up of a large sphere (peritoneum) containing two hemispheres (liver and spleen). The space between peritoneum and inner organs was defined with two different approaches and assessed under impact conditions. The first is a Meshfree Space approach, e.g. consider the space as a perfect gas. The second approach, Meshed Space, entailed adding volumetric elements in the empty space. From each approach, one optimal configuration was identified regarding the recorded force vs. compression, the mobility of inner organs and the space incompressibility. This space has a considerable influence on the behavior of the FEM and mainly on the applied loadings of inner organs (difference reaching 70% according to the configuration). For the first approach, the incompressible gas is designated because it guarantees space incompressibility (vf/vi=1) and inner organs loading with the lowest delay (for high impact velocity: Peak force = 89N, compression 47%). For the second approach, the discontinuous volumetric mesh is preferred because it promotes space incompressibility (vf/vi=0.94) and acceptable force reaction (for high impact velocity: Peak force = 97N, compression 49%). The current study shows the importance of this space on the human FEMs cavities behavior and proposes 2 configurations able to be used in a future study including detailed FEM.
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    ABSTRACT: Mesenteric avulsion, corresponding to a tearing of intestine's root, generally results from high deceleration in road accidents. The biomechanical analysis of bowel and mesenteric injuries is a major challenge for injury prevention, particularly because seat belt restraint may paradoxically increase their risk of occurrence. The aim of this study was to identify the biomechanical behavior of mesentery and small bowel (MSB) tissue samples under dynamical loading conditions. A dedicated test bench was designed in order to perform tensile tests on fresh MSB porcine specimens, with quasi-static (1 mm/s) and dynamic (100 mm/s) loading conditions. The mechanical behavior of MSB specimens was investigated and compared to isolated mesenteric and isolated small bowel specimens. The results show a high sensitivity of MSB stiffness (1.0 ± 0.2 and 1.3 ± 0.3 N/mm at 1 and 100 mm/s, p = 0.001) and ultimate force (22 ± 5 and 35 ± 8 N at 1 and 100 mm/s, p = 0.001) to the loading rate but not for the displacement at failure. This leads to postulate on a failure criteria based on strain level regardless of the strain rate. These experimental results could be further used to develop refined finite element models and to further investigate on injury mechanisms associated to seat belt restraints, as well as to evaluate and improve protective devices.
    Medical & Biological Engineering & Computing 11/2014; 53(2). DOI:10.1007/s11517-014-1212-4 · 1.73 Impact Factor
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    ABSTRACT: Study Design: Detailed biomechanical analysis of the anchorage performance provided by different pedicle screw design 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 (FEM). Summary of Background Data: Pedicle screw fixation is commonly used in the treatment of spinal pathologies. However, there is little consensus on the selection of an optimal screw type, size, and insertion trajectory depending on vertebra dimension and shape. Methods: Different screw diameters and lengths, threads and insertion trajectories were computationally tested using a design of experiment (DOE) approach. A detailed FEM of an L3 vertebra was created including elastoplastic bone properties and contact interactions with the screws. Loads and boundary conditions were applied to the screws to simulate axial pullout tests. Force-displacement responses and internal stresses were analyzed to determine the specific effects of each parameter. Results: The DOE analysis revealed significant effects (P<0.01) for all tested principal parameters along with the interactions between diameter and trajectory. Screw diameter had the greatest impact on anchorage performance. The best insertion trajectory to resist pullout involved placing the screw threads closer to the pedicle walls using the straight-forward insertion technique, which showed the importance of the cortical layer grip. The simulated cylindrical single-lead thread screws presented better biomechanical anchorage than the conical dual-lead thread screws in axial loading conditions. Conclusions: The model made it possible to quantitatively measure the effects of both screw design characteristics and surgical choices, enabling to recommend strategies to improve single pedicle screw performance under axial loading.
    Journal of Spinal Disorders & Techniques 07/2014; Publish Ahead of Print. DOI:10.1097/BSD.0000000000000151 · 2.20 Impact Factor
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    Omar Chebil · Michel Behr · Florent Auriault · Pierre-Jean Arnoux
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    ABSTRACT: The spleen is a frequently injured abdominal organ in road accidents, with an injury frequency close to 30 %. The splenic avulsion exhibit a significant ratio of morbidity. It is clinically described as the complete failure of the pancreatico-splenic ligament (PSL) which is composed of splenic vessels and connective tissues. What are the biomechanical mechanisms involved with spleen avulsion? Is it possible to quantify tolerance levels of PSL structure? The current work combines both experimental and finite element (FE) investigations to determine the splenic avulsion process. Tensile tests on 13 PSL samples were performed up to failure. The experimental results provide reference data for model validation and showed a failure process starting at a peak force of 70 ± 34 N combined with a peak strain of 105 ± 26 %. In an attempt to identify possible vessel ruptures within the PSL, a FE model of the PSL was developed including both vessels and connective tissues. The vessel wall behaviour up to failure was reproduced using an Ogden law and calibrated by inverse analysis according to literature data. The connective tissues function was modelled by a cohesion-loss interface. Once model correlation to experimental results was achieved, numerical simulation revealed that haemorrhage could occur even before the maximum peak is reached. Indeed, the first vessel ruptures were recorded at a strain of 92 % at the upper lobe vein.
    Medical & Biological Engineering & Computing 06/2014; 52(8). DOI:10.1007/s11517-014-1166-6 · 1.73 Impact Factor
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    Omar Chebil · Pierre-Jean Arnoux · Michel Behr
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    ABSTRACT: Road accidents can lead to abdominal injuries ranging from severe to lethal, that include hemorrhage of organs and their attachment system. A good understanding and prediction of abdominal injuries therefore requires investigation of the mechanical properties of the attachment systems of abdominal organs. In particular, the gastrocolic ligament (GCL) is one major link between the stomach and the transverse colon. This study aims to investigate the mechanical properties of the GCL under very low and high strain rate uniaxial tensile tests until failure. Thirty-five GCL samples were dissected from 7 embalmed cadavers and tested at a rate of 1 mm/s and 1 m/s. Incidence of freezing was also evaluated. The mechanical response of GCL samples showed an approximately bilinear curve. Within the first linear region (less than 5% of ligament strain), the apparent elastic modulus was estimated at 247±144 kPa, while in the second region, it was estimated at 690±282 kPa. The average failure stress (σfail) and failure strain (εfail) were 131.6±50 kPa and 29%±8%, respectively. High strain rate loading also showed high sensitivity to strain rate. The estimated GCL mechanical properties in this study can be implemented in finite element models of the abdomen to further investigate the mechanical contribution of the organ attachment system under traumatic loading conditions.
    Journal of Applied Biomaterials and Fundamental Materials 04/2014; 13(2). DOI:10.5301/jabfm.5000193 · 1.50 Impact Factor
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    ABSTRACT: Study Design. Measurements of cervical and thoraco-lumbar human spinal cord (SC) geometry based on in vivo MRI and investigation of morphological "invariants".Objective. The current work aims at providing morphological features of the complete in vivo human normal spinal cord and at investigating possible "invariant" parameters that may serve as normative data for individualized study of SC injuries.Summary of Background Data. Few in vivo MR-based studies have described human SC morphology at the cervical level, and similar description of the entire SC only relies on post-mortem studies, which may be prone to atrophy biases. Moreover, large inter-individual variations currently limit the use of morphological metrics as reference for clinical applications or as modeling inputs.Methods. Absolute metrics of SC (transverse and antero-posterior diameters, anterior and posterior horns width, cross-sectional SC area and white matter percentage) were measured using semi-automatic segmentation of high resolution in vivo T2*-weighted transverse images acquired at 3T, at each SC level, on healthy young (N = 15) and older (N = 8) volunteers. Robustness of measurements, effects of subject, age, or sex, as well as comparison to previously published post mortem data were investigated using statistical analyses (Separate analysis of variance, Tukey-HSD, Bland-Altman). Normalized-to-C3 parameters were evaluated as invariants using a leave-one-out analysis. Spinal canal parameters were measured and occupation ratio (OR) border values were determined.Results. Metrics of SC morphology showed large intra- and inter-individual variations, up to 30% and 13% respectively in average. Sex had no influence except on posterior horns width (p<0.01). Age-related differences were observed for anteroposterior diameter and white matter percentage (p<0.05) and all postmortem metrics were significantly lower than in vivo values (p<0.001). In vivo normalized SC area and diameters appeared to be invariants (R>0.74, RMSE<10%) Finally, minimal and maximal OR were 0.2 and 0.6, respectively.Conclusion. This study presented morphological characteristics of the complete in vivo human spinal cord. Significant differences linked to age and postmortem state have been identified. Morphological "invariants" that could be used to accurately calculate the normally expected morphology, were also identified. These observations should benefit to biomechanical and spinal cord pathology studies.
    Spine 11/2013; 39(4). DOI:10.1097/BRS.0000000000000125 · 2.30 Impact Factor
  • Léo Fradet · Yvan Petit · Eric Wagnac · Carl-Eric Aubin · Pierre-Jean Arnoux
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    ABSTRACT: 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 type was computationally simulated to assess the fracture process. A refined finite element model of three vertebrae and intervertebral connective tissues was subjected to 51 different dynamic loading conditions divided into four categories: compression, shear, distraction and torsion. Fracture initiation and propagation were analyzed, and time and energy at fracture initiation were computed. To each fracture pattern described in the clinical literature were associated one or several of the simulated fracture patterns and corresponding loading conditions. When compared to each other, torsion resulted in low-energy fractures, compression and shear resulted in medium energy fractures, and distraction resulted in high-energy fractures. Increased velocity resulted in higher-energy fracture for similar loadings. The use of a finite element model provided quantitative characterization of fracture patterns occurrence complementary to clinical and experimental studies, allowing to fully understand spinal fracture biomechanics.
    Medical & Biological Engineering 10/2013; 52(1). DOI:10.1007/s11517-013-1124-8 · 1.73 Impact Factor
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    ABSTRACT: To date, developing geometrically personalized and detailed solid finite element models of the spine remains a challenge, notably due to multiple articulations and complex geometries. To answer this problem, a methodology based on a free form deformation technique (kriging) was developed to deform a detailed reference finite element mesh of the spine (including discs and ligaments) to the patient-specific geometry of 10 and 82-year old asymptomatic spines. Different kriging configurations were tested: with or without smoothing, and control points on or surrounding the entire mesh. Based on the results, it is recommended to use surrounding control points and smoothing. The mean node to surface distance between the deformed and target geometries was 0.3 mm ± 1.1. Most elements met the mesh quality criteria (95%) after deformation, without interference at the articular facets. The methods novelty lies in the deformation of the entire spine at once, as opposed to deforming each vertebra separately, with surrounding control points and smoothing. This enables the transformation of reference vertebrae and soft tissues to obtain complete and personalized FEMs of the spine with minimal post-processing to optimize the mesh.
    IEEE transactions on bio-medical engineering 02/2013; 60(7). DOI:10.1109/TBME.2013.2246865 · 2.35 Impact Factor
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    ABSTRACT: Intestinal injuries are responsible for significant morbidity and mortality arising from trauma to the abdomen. The biomechanical characterisation of the small intestine allows for the understanding of the pathophysiological mechanisms responsible for these injuries. Studies reported in the literature focus principally on quasi-static tests, which do not take into account the stresses experienced during high kinetic trauma. In addition, the use of embalmed human tissue can alter the recorded response. The stress-strain curves from 43 tensile tests performed at 1 m/s were analysed. Samples were prepared from four fresh human intestines and from four embalmed cadaveric intestines. The data indicated a two-phase response, with each response consisting of a quasi-linear increase in the stress followed by an inflection in the curve before a peak preceding the loss of stress. The fresh tissue was more deformable than the embalmed tissue, and its first peak stress was lower (P = 0.034). A complementary histological analysis was performed. The results of the analysis enable an investigation of the response of the intestinal wall layers to stress as a two-layer structure and highlight the high sensitivity of the structure's mechanical behaviour to the speed of loading and the method of preservation.
    Medical & Biological Engineering 10/2012; 50(12). DOI:10.1007/s11517-012-0964-y · 1.73 Impact Factor
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    ABSTRACT: The temporal bone shields sensorineural, nervous, and vascular structures explaining the potential severity and complications of trauma related to road and sport accidents. So far, no clear data are available on the exact mechanisms involved for fracture processes. Modelization of structures helps to answer these concerns. Our objective was to design a finite element model of the petrous bone structure to modelize temporal bone fracture propagation in a scenario of lateral impact. A finite element model of the petrous bone structure was designed based on computed tomography data. A 7-m/s lateral impact was simulated to reproduce a typical lateral trauma. Results of model analysis was based on force recorded, stress level on bone structure up to induce a solution of continuity of the bony structure. Model simulation showed that bone fractures follow the main axes of the petrous bone and occurred in a 2-step process: first, a crush, and second, a massive fissuration of the petrous bone. The lines of fracture obtained by simulation of a lateral impact converge toward the middle ear region. This longitudinal fracture is located at the mastoid-petrous pyramid junction. Using this model, it was possible to map petrous bone fractures including fracture chronology and areas of fusion of the middle ear region. This technique may represent a first step to investigate the pathophysiology of the petrous bone fractures, aiming to define prognostic criteria for patients' care.
    Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 06/2012; 33(4):651-4. DOI:10.1097/MAO.0b013e31824f9947 · 1.79 Impact Factor
  • Eric Wagnac · Pierre-Jean Arnoux · Anaïs Garo · Carl-Eric Aubin
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    ABSTRACT: 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 components and material laws that include strain rate dependency, bone fracture, and ligament failure. The FEM was validated against published experimental data and used to compare the initiation sites of spinal injuries under low (LD) and high (HD) dynamic compression, flexion, extension, anterior shear, and posterior shear. Simulations resulted in force-displacement and moment-angular rotation curves well within experimental corridors, with the exception of LD flexion where angular stiffness was higher than experimental values. Such a discrepancy is attributed to the initial toe-region of the ligaments not being included in the material law used in the study. Spinal injuries were observed at different initiation sites under LD and HD loading conditions, except under shear loads. These findings suggest that the strain rate dependent behavior of spinal components plays a significant role in load-sharing and failure mechanisms of the spine under different loading conditions.
    Medical & Biological Engineering 05/2012; 50(9):903-15. DOI:10.1007/s11517-012-0908-6 · 1.73 Impact Factor
  • Cécile Conte · Stéphane Garcia · Pierre-Jean Arnoux · Catherine Masson
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    ABSTRACT: To prevent abdominal organs' traumas in crash situations, the definition of efficient safety devices should be based on a detailed knowledge of human tolerance, i.e., injury mechanisms and related injury criteria. This knowledge should be based on experimental observation of these mechanisms through damage and failure analysis. In this study, 10 human cadaveric livers are uniaxially compressed using three different loading velocities (0.0013, 0.2, and 1 m/s). Injuries induced are analyzed at two observation levels through a macroscopic study of internal and external cracks and a histologic study of damage initiation. Liver global behavior is similar for the three loading velocities, but loading rate seems to influence the stiffness and the severity of failure process. Macroscopic injury analysis showed four patterns of laceration because of organ spreading during its compression exhibiting liver structure incidence. Histologic analysis shows two different damage occurrences: microcracking and cavitation. The crack propagation is observed to occur preferentially within the lobules. Influence of the vascular system is also highlighted. Both macroscopic and histologic injuries obtained are relevant with those clinically observed under trauma situations. Based on experimental investigation of human liver under compression, this work provides a multiscale evaluation of injury process coupling mechanical and histologic analysis. Injury mechanisms postulated involve vascular structures and capsule. All this information is essential for the design of dedicated behavior laws and finite element models.
    03/2012; 72(3):727-32. DOI:10.1097/TA.0b013e3182395e68
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    Eric Wagnac · Pierre-Jean Arnoux · Anaïs Garo · Marwan El-Rich · Carl-Eric Aubin
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    ABSTRACT: 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 load rate dependency. The aim of this study was to identify hyperelastic material properties that ensure a more biofidelic simulation of the IVD under a fast dynamic compressive load. A hyperelastic material law based on a first-order Mooney-Rivlin formulation was implemented in a detailed FEM of a L2-L3 functional spinal unit (FSU) to represent the mechanical behavior of the IVD. Bony structures were modeled using an elasto-plastic Johnson-Cook material law that simulates bone fracture while ligaments were governed by a viscoelastic material law. To mimic experimental studies performed in fast dynamic compression, a compressive loading velocity of 1 m/s was applied to the superior half of L2, while the inferior half of L3 was fixed. An exploratory technique was used to simulate dynamic compression of the FSU using 34 sets of hyperelastic material constants randomly selected using an optimal Latin hypercube algorithm and a set of material constants derived from quasi-static experiments. Selection or rejection of the sets of material constants was based on compressive stiffness and failure parameters criteria measured experimentally. The two simulations performed with calibrated hyperelastic constants resulted in nonlinear load-displacement curves with compressive stiffness (7335 and 7079 N/mm), load (12,488 and 12,473 N), displacement (1.95 and 2.09 mm) and energy at failure (13.5 and 14.7 J) in agreement with experimental results (6551 ± 2017 N/mm, 12,411 ± 829 N, 2.1 ± 0.2 mm and 13.0 ± 1.5 J respectively). The fracture pattern and location also agreed with experimental results. The simulation performed with constants derived from quasi-static experiments showed a failure energy (13.2 J) and a fracture pattern and location in agreement with experimental results, but a compressive stiffness (1580 N/mm), a failure load (5976 N) and a displacement to failure (4.8 mm) outside the experimental corridors. The proposed method offers an innovative way to calibrate the hyperelastic material properties of the IVD and to offer a more realistic simulation of the FSU in fast dynamic compression.
    Journal of Biomechanical Engineering 10/2011; 133(10):101007. DOI:10.1115/1.4005224 · 1.78 Impact Factor
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    Cécile Conte · Catherine Masson · Pierre-Jean Arnoux
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    ABSTRACT: To prevent traumas to abdominal organs, the selection of efficient safety devices should be based on a detailed knowledge of injury mechanisms and related injury criteria. In this sense, finite element (FE) simulation coupled with experiment could be a valuable tool to provide a better understanding of the behaviour of internal organs under crash conditions. This work proposes a methodology based on inverse analysis which combines exploration process optimisation and robustness study to obtain mechanical behaviour of the complex structure of the liver through FE simulation. The liver characterisation was based on Mooney-Rivlin hyperelastic behaviour law considering whole liver structure under uniform quasi-static compression. With the global method used, the model fits experimental data. The variability induced by modelling parameters is quantified within a reasonable time.
    Computer Methods in Biomechanics and Biomedical Engineering 05/2011; 15(9):993-9. DOI:10.1080/10255842.2011.569884 · 1.77 Impact Factor

Publication Stats

139 Citations
57.05 Total Impact Points


  • 2008–2015
    • Aix-Marseille Université
      • • Centre de Résonance Magnétique Biologique et Médicale (UMR 7339 CRMBM)
      • • Laboratoire de biomécanique appliquée (UMR_T 24 LBA)
      Marsiglia, Provence-Alpes-Côte d'Azur, France
  • 2011
    • Institut Français des Sciences et Technologies des Transports, de l’Aménagement et des Réseaux
      • Laboratoire de Biomécanique Appliquée (LBA)
      Champs, Île-de-France, France
  • 2010–2011
    • Montreal Polytechnic
      • Département de génie mécanique
      Montréal, Quebec, Canada