Article
Biotechnology & Applied Microbiology
Cunheng Yang, Fumin Wang, Xingxing Huang, Hao Zhang, Meng Zhang, Junxiao Gao, Shengbo Shi, Fuyang Wang, Fangjun Yang, Xiaobing Yu
Summary: Investigation showed that mineralized collagen modified PMMA bone cement has similar stress distribution to common bone cement and has advantages of promoting bone regeneration, good biocompatibility, and improved properties. It has comparable support strength and has great potential for development.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2023)
Article
Mathematics, Applied
Guofang Chen, Junliang Lv, Xinye Zhang
Summary: This paper solves a second-order nonlinear elliptic equation using the finite volume element method and provides rigorous error estimates. The computational domain is divided into convex quadrilateral meshes. The isoparametric bilinear element space is chosen as the trial function space and the piecewise constant function space is chosen as the test function space. The boundedness and coercivity of the bilinear form are proved on the h(2)-parallelogram mesh, and the existence and uniqueness of the numerical solution are established using the Brouwer fixed point theorem. The paper also derives estimates for parallel to(del(u-u(h))parallel to and parallel to u-u(h)parallel to(0) under certain regularity assumptions. Numerical experiments on quadrilateral meshes are conducted to calculate the convergence orders in H-1 and L-2 norms, which align with the theoretical results.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2023)
Article
Engineering, Multidisciplinary
Yanlong Zhang, Yanhui Zhou, Jiming Wu
Summary: This article investigates a 2D nonlinear time-fractional Rayleigh-Stokes problem using quadratic finite volume element schemes on triangular meshes. The Caputo fractional derivative is discretized through a specific formula, and a two step scheme is used to approximate the time first-order derivative. Results show that the L-2 error estimate of one scheme is O(h(3) + Δt(2)), while others are O(h(2) + Δt(2)), indicating varying levels of accuracy.
CMES-COMPUTER MODELING IN ENGINEERING & SCIENCES
(2021)
Article
Mechanics
H. Luo, Z. Hooshmand-Ahoor, K. Danas, J. Diani
Summary: In this study, the nonlinear behavior of a soft matrix with a high volume fraction (up to 55%) of monodisperse spherical inclusions (rigid particles or voids) is numerically investigated using finite element simulations and analytical approaches. A successive remeshing and solution mapping technique is used to address the issue of mesh distortion at large strains, allowing for large macroscopic deformations. A general algorithm is proposed and implemented to remesh a finitely strained domain with randomly distributed inclusions of arbitrary shape. The simulation results show that the stress-stretch uniaxial tension response of a neo-Hookean elastic matrix filled with rigid particles can be well approximated by a neo-Hookean material with an effective shear modulus that depends on the volume fraction of the inclusions. The study also demonstrates that sixty four monodisperse spheres provide accurate results for large deformations while maintaining a reasonable CPU-time. The finite element data serve as a tool for assessing analytical homogenization models and filling the gap for large volume fractions of inclusions.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Endocrinology & Metabolism
Chengqiang Zhou, Shaolong Huang, Yifeng Liao, Han Chen, Yazhong Zhang, Hua Li, Ziqiang Zhu, Yunqing Wang
Summary: This study investigates the correlation between the larger side bone cement volume/vertebral body volume ratio (LSBCV/VBV%) and adjacent vertebral compression fracture (AVCF) in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fracture (OVCF). The results show that bone mineral density (BMD), bone cement disc leakage, and LSBCV/VBV% are independent risk factors for AVCF after PVP.
FRONTIERS IN ENDOCRINOLOGY
(2023)
Article
Oncology
Biao Wang, Yi Zhan, Yesheng Bai, Lingbo Kong, Liang Li, Haiping Zhang, Simin He, Dingjun Hao
Summary: This study developed a novel bone cement bridging screw system for strengthening the vertebrae in patients with Kummell disease. The results showed that the bridging screw system combined with vertebroplasty has better stability and safety compared to single vertebroplasty and vertebroplasty combined with pediculoplasty.
AMERICAN JOURNAL OF TRANSLATIONAL RESEARCH
(2022)
Article
Medicine, General & Internal
Yuanzheng Song, Xia Pang, Fahao Zhu
Summary: Burst fractures of the thoracolumbar spine often result in damage to the spinal column and posterior structures, leading to compression of the spinal cord or cauda equina and neurological dysfunction. The use of positioning and distraction techniques can effectively restore the injured vertebrae to their normal height and alignment. Decompression of the posterior longitudinal ligament can help push the bone block in the spinal canal back into place, achieving a successful reduction.
Article
Clinical Neurology
Sang-Youn Song, Sung Wook Kang, Seong Hee Cho, Se-Joon Heo, Min Goo Cho, Young-Jin Park, Se Heang Oh, Gu-Hee Jung, Dong-Hee Kim
Summary: This study determined the ideal amount of bone cement and injection site for Kyphoplasty (KP) surgery using the finite element method. The results showed that increasing the amount of cement significantly increased the stress on the upper and lower end plates of the injected segment, and there is a potential risk of adjacent fracture if the cement amount exceeds a certain threshold. Centrally injected bone cement can lower the risk of adjacent fracture.
WORLD NEUROSURGERY
(2022)
Article
Engineering, Multidisciplinary
Juan Michael Sargado, Eirik Keilegavlen, Inga Berre, Jan Martin Nordbotten
Summary: Numerical simulations of brittle fracture using phase-field methods often face challenges in accurately modeling fully developed cracks due to the limitations of using low order elements for the phase-field. By combining a standard linear finite element discretization with a finite volume approximation of the phase-field evolution equation on the same mesh, looser mesh refinement restrictions can be achieved, resulting in significant reductions in computational costs.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Mechanics
Marcello Congro, Deane Roehl, Cristian Mejia
Summary: This paper introduces a new numerical model for simulating the mechanical behavior of cement composite materials at a mesoscale level, with a focus on the coupling of fiber and cementitious elements without considering fiber dispersion. Through simulations of direct tensile and bending tests, the results demonstrate the efficiency and robustness of the proposed model.
COMPOSITE STRUCTURES
(2021)
Article
Biotechnology & Applied Microbiology
Haowen Dai, Yang Liu, Qing Han, Aobo Zhang, Hao Chen, Yang Qu, Jincheng Wang, Jianwu Zhao
Summary: This study compared the biomechanical differences between unilateral percutaneous vertebroplasty (UPVP) and bilateral percutaneous vertebroplasty (BPVP) using finite element analysis. The results showed that BPVP could balance vertebral body stress, reduce intervertebral disc stress, and offer stability advantages compared to UPVP. Therefore, BPVP has the potential to reduce postoperative complications and provide promising clinical effects.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2022)
Article
Engineering, Biomedical
Marta Pena Fernandez, Sebastian J. Sasso, Samuel McPhee, Cameron Black, Janos Kanczler, Gianluca Tozzi, Uwe Wolfram
Summary: Bone regeneration in critical-sized defects is a clinical challenge. Nonlinear micro finite element models can predict the biomechanical strength and microdamage onset in newly formed bone. Experimental validation and analysis reveal that microdamage occurs at low strains.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2022)
Article
Computer Science, Interdisciplinary Applications
Alireza Beheshti, Reza Ansari
Summary: This paper focuses on the geometrically nonlinear analysis of laminated composite shells using the finite element method. A higher-order shell model with extensible directors possessing twelve parameters is used to extract the exact Green-Lagrange strains and the three-dimensional second Piola-Kirchhoff stress tensor based on the base vectors of the shell mid-surface. The weak form of governing equations is derived using the principle of virtual work. A computationally efficient four-node shell element is designed to address locking problems and the ANS approach and assumed strain scheme are employed. Standard benchmarks for isotropic materials with geometric nonlinearity are solved to examine the performance of the proposed shell element, and results of thin and thick layered composite structures are presented.
ENGINEERING WITH COMPUTERS
(2023)
Article
Mathematics, Applied
Huo Fan
Summary: The volume-coordinate system (VCS) is crucial in finite element method (FEM). Currently, the number of coordinate components in all VCSs is equal to the number of faces of polyhedral elements. This study presents a new 3-component VCS based on hexahedron, which can be applied to degenerated solids such as tetrahedron and 5-surface solids. Unlike previous VCS, the new VCS is shape-independent and combines the advantages of local natural coordinate system and Cartesian coordinate system.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2023)
Article
Engineering, Geological
S. R. T. Tripuraneni, Aleksei Novikov, Denis Voskov
Summary: This paper introduces a positivity preserving Nonlinear Two Point Stress Approximation (NTPSA) based on the recently developed collocated Finite Volume scheme for linear elastic mechanics, which is extensively used in reservoir modeling. The convergence of the scheme is tested with a homogeneous anisotropic stiffness tensor.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2023)
Article
Endocrinology & Metabolism
Mathieu Simon, Michael Indermaur, Denis Schenk, Seyedmahdi Hosseinitabatabaei, Bettina M. Willie, Philippe Zysset
Summary: Osteogenesis Imperfecta (OI) is a genetic bone disorder characterized by impaired collagen synthesis, altered trabecular bone structure, and reduced bone mass. This study used HR-pQCT to compare the bone morphology of OI patients with healthy controls. The results showed that OI samples had significantly lower BV/TV and trabecular number, higher trabecular separation and standard deviation, but no difference in trabecular thickness compared to healthy controls. The stiffness analysis revealed that the fabric-elasticity relationships between OI and healthy individuals were similar when the ROIs were sufficiently homogeneous.
Article
Endocrinology & Metabolism
Lilian Sewing, Laura Potasso, Sandra Baumann, Denis Schenk, Furkan Gazozcu, Kurt Lippuner, Marius Kraenzlin, Philippe Zysset, Christian Meier
Summary: Type 1 diabetes (T1DM) is associated with an increased risk of nonvertebral fractures, and the influence of glycemic control and microvascular disease on skeletal health in long-standing T1DM is not well understood. This study found that patients with long-standing T1DM had lower bone mineral density (BMD), decreased bone turnover, and weaker bones at the ultradistal tibia compared to non-diabetic controls. The presence of diabetic peripheral neuropathy was found to contribute to the altered cortical microarchitecture and reduced bone strength in T1DM patients.
JOURNAL OF BONE AND MINERAL RESEARCH
(2022)
Article
Biophysics
Denis Schenk, Philippe Zysset
Summary: The present study aims to identify an optimal, personalized, multiaxial load case at the distal section of the human radius using in vivo HR-pQCT-based isotropic, homogenized finite element (hFE) analysis. The results show that the optimized linear six-degree-of-freedom load case achieves a more homogeneous tissue loading and can absorb more energy.
BIOMECHANICS AND MODELING IN MECHANOBIOLOGY
(2023)
Article
Engineering, Biomedical
Marta Pena Fernandez, Jakob Schwiedrzik, Alexander Burki, Francoise Peyrin, Johann Michler, Philippe K. Zysset, Uwe Wolfram
Summary: The development of treatment strategies for skeletal diseases relies on the understanding of bone mechanical properties in relation to its structure at different length scales. In this study, the anisotropic crack propagation, deformation, and fracture of ovine cortical bone under different indenters were investigated using in situ high-resolution SR μCT indentation testing and digital volume correlation. The results revealed the significant dependence of the crack development on the anisotropy ahead of the tip, with lower strains and smaller crack systems developing in samples indented in the transverse material direction. The study sheds light on the importance of three-dimensional investigation of bone deformation and fracture behavior to explore the mechanisms of bone failure.
ACTA BIOMATERIALIA
(2023)
Article
Engineering, Biomedical
Elham Alizadeh, Sadik Omairey, Philippe Zysset
Summary: In this study, we developed a 3D non-linear finite element unit-cell model to investigate the behavior of mineralized collagen fibril arrays after yielding. The model was compared with experimental tests and showed good quantitative agreement. The simulation results revealed the dominant role of mineralized collagen fibrils in load bearing prior to yielding and the initiation of damage through debonding and sliding at the interface between the fibrils and the matrix. The model's integration into larger length scales could provide a detailed understanding of the post-yield behavior and failure mechanisms of trabecular and cortical bone.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2023)
Article
Geriatrics & Gerontology
Christina Wapp, Emmanuel Biver, Serge Ferrari, Philippe Zysset, Marcel Zwahlen
Summary: The aim of this study was to develop a statistical model to predict future fall rates in older adults using personalized risk predictors. The results showed that the number of prior falls was a strong risk factor, with individuals who have experienced three or more falls being more likely to fall multiple times again.
Article
Biotechnology & Applied Microbiology
Alice Dudle, Yvan Gugler, Michael Pretterklieber, Serge Ferrari, Kurt Lippuner, Philippe Zysset
Summary: Osteoporosis is currently diagnosed based on 2D DXA scans, but this method does not consider the 3D bone geometry and density distribution. QCT scans combined with FE analysis can provide improved femoral strength predictions, but high radiation dose and cost limit its usage. The 3D-Shaper software reconstructs the 3D shape and density distribution of the femur from 2D DXA scans, which could provide a more accurate estimation of femoral strength.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2023)
Article
Engineering, Multidisciplinary
Michael Woeltje, Liesa Kuenzelmann, Basak Belguecan, Andreas S. Croft, Benjamin Voumard, Stefan Bracher, Philippe Zysset, Benjamin Gantenbein, Chokri Cherif, Dilbar Aibibu
Summary: Low back pain is commonly caused by degeneration of the intervertebral discs. Current treatments are unable to effectively restore the function of the discs. This study aimed to reconstruct the annulus fibrosus and nucleus pulposus of the intervertebral disc using silk as a biomaterial. The researchers developed an embroidered structure to mimic the fiber orientation and lamellar structure of the annulus fibrosus, and used fiber additive manufacturing to replicate the fiber network of the nucleus pulposus and create a porous 3D structure.
Article
Engineering, Biomedical
Alexander Groetsch, Aurelien Gourrier, Daniele Casari, Jakob Schwiedrzik, Jonathan D. Shephard, Johann Michler, Philippe K. Zysset, Uwe Wolfram
Summary: The hierarchical design of bio-based nanostructured materials allows them to combine unique structure-mechanical properties. Water, as a main component in bone, plays a crucial role in its mechanical behavior. In this study, a direct connection between experiment and model is established to investigate the effect of rehydration on the mechanical properties of mineralized collagen fibers. The results show that rehydration reduces the yield stress, compressive strength, and stiffness of the fibers, with a greater effect on stresses than strains. The findings provide insights into the water-mediated structuring of bone apatite and its implications for mechanical behavior.
ACTA BIOMATERIALIA
(2023)
Article
Endocrinology & Metabolism
Matthias Walle, Danielle E. Whittier, Denis Schenk, Penny R. Atkins, Michael Blauth, Philippe Zysset, Kurt Lippuner, Ralph Mueller, Caitlyn J. Collins
Summary: This study developed bone mechanoregulation markers and their precision using participants from two cohorts. The results showed that bone formation occurred in high-strain regions and bone resorption occurred in low-strain regions for all participants, indicating a consistent response to mechanical stimuli. This work provides novel and robust bone mechanoregulation markers for designing future clinical studies.
Article
Endocrinology & Metabolism
Danielle E. Whittier, Matthias Walle, Denis Schenk, Penny R. Atkins, Caitlyn J. Collins, Philippe Zysset, Kurt Lippuner, Ralph Mueller
Summary: The study established a multi-stack registration protocol for evaluating longitudinal HR-pQCT images and assessing the accuracy and precision error. Results showed that most scans improved or maintained stack alignment when multi-stack registration was implemented, with significant decrease in false discovery rate of bone remodelling events after multi-stack registration. The precision error was significantly reduced or remained unchanged in most bone morphology and micro-finite element analysis parameters.
Article
Endocrinology & Metabolism
Michael Indermaur, Daniele Casari, Tatiana Kochetkova, Bettina M. Willie, Johann Michler, Jakob Schwiedrzik, Philippe Zysset
Summary: Osteogenesis imperfecta (OI) is a genetic bone disease that leads to an increased risk of fractures. This study investigated the tensile properties of healthy and OI bone extracellular matrix (ECM). The results showed that OI bone ECM exhibited similar tensile properties to healthy bone, and the mechanical properties were primarily influenced by the orientation of mineralized collagen fibers (MCF) and the degree of bone mineralization (DBM).
Correction
Geriatrics & Gerontology
Christina Wapp, Anne-Gabrielle Mittaz Hager, Roger Hilfiker, Philippe Zysset
FRONTIERS IN AGING
(2023)
Proceedings Paper
Computer Science, Interdisciplinary Applications
Marzieh Ovesy, Philippe K. Zysset
Summary: This study simulated the implantation process and evaluated the influence of press-fit on the primary stability of total hip arthroplasty. The results showed that a higher press-fit increased the implantation force, while a lower press-fit provided better stability during the loading cycle.
COMPUTER METHODS, IMAGING AND VISUALIZATION IN BIOMECHANICS AND BIOMEDICAL ENGINEERING II
(2023)
Meeting Abstract
Endocrinology & Metabolism
Michael Indermaur, Daniele Casari, Tatiana Kochetkova, Bettina Willie, Johann Michler, Jakob Schwiedrzik, Philippe Zysset
JOURNAL OF BONE AND MINERAL RESEARCH
(2022)