Journal of Biomechanical Engineering This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

The Effects of Bone Microstructure on Subsidence Risk for ALIF, LLIF, PLIF, and TLIF Spine Cages
Several approaches (anterior, posterior, lateral, and transforaminal) are used in lumbar fusion surgery. However, it is unclear whether one of these approaches has the greatest subsidence risk as published clinical rates of cage subsidence vary widely (7 –70%). Specifically, there is limited data on how a patient's endplate morphometry and trabecular bone quality influences cage subsidence risk. Therefore, this study compared subsidence (stiffness, maximum force, and work) between anterior (ALIF), lateral (LLIF), posterior (PLIF), and transforamin al (TLIF) lumbar interbody fusion cage designs to understand the impact of...
Source: Journal of Biomechanical Engineering - January 18, 2019 Category: Biomedical Engineering Source Type: research

Validation of an In Vivo Medical Image-Based Young Human Lumbar Spine Finite Element Model
Mathematical models of the human spine can be used to investigate spinal biomechanics without the difficulties, limitations, and ethical concerns associated with physical experimentation. Validation of such models is necessary to ensure that the modeled system behavior accurately represents the physics of the actual system. The goal of this work was to validate a medical image-based nonlinear lumbosacral spine finite element model of a healthy 20-yr-old female subject under physiological moments. Range of motion (ROM), facet joint forces (FJF), and intradiscal pressure (IDP) were compared with experimental values and valid...
Source: Journal of Biomechanical Engineering - January 18, 2019 Category: Biomedical Engineering Source Type: research

Reduced Order Models for Transstenotic Pressure Drop in the Coronary Arteries
In this study, we evaluate the capability of different hydrodynamic models to compute transstenotic pressure drop. Models range from algebraic formulae to one-dimensional (1D), two-dimensional (2D), and 3D time-dependent CFD simulations. Although several algebraic pressure-drop formulae have been proposed in the literature, these models were found to exhibit wide variation in predictions. Nonetheless, we demonstrate an algebraic formula that provides consistent predictions with 3D CFD results for various changes in stenosis severity, morphology, location, and flow rate. The accounting of viscous dissipation and flow separa...
Source: Journal of Biomechanical Engineering - January 18, 2019 Category: Biomedical Engineering Source Type: research

Design of a Novel Electrode of Radiofrequency Ablation for Large Tumors: In Vitro Validation and Evaluation
In a prior study, we proposed a novel monopolar expandable electrode (MEE) for use in radiofrequency ablation (RFA). The purpose of our work was to now validate and evaluate this electrode using on in vitro experimental model and computer simulation. Two commercially available RF electrodes (conventional electrode (CE) and umbrella electrode (UE)) were used to compare the ablation results with the novel MEE using an in vitro egg white model and in vivo liver tumor model to verify the efficacy of MEE in the large tumor ablation, respectively. The sharp increase in impedance during RFA procedures was taken as the termination...
Source: Journal of Biomechanical Engineering - January 18, 2019 Category: Biomedical Engineering Source Type: research

Probing Mechanical Properties of Brain in a Tuberous Sclerosis Model of Autism
Causes of autism spectrum disorders (ASD) are understood poorly, making diagnosis and treatment challenging. While many studies have investigated the biochemical and genetic aspects of ASD, whether and how mechanical characteristics of the autistic brain can modulate neuronal connectivity and cognition in ASD are unknown. Previously, it has been shown that ASD brains are characterized by abnormal white matter and disorganized neuronal connectivity; we hypothesized that these significant cellular-level structural changes may translate to changes in the mechanical properties of the autistic brain or regions therein. Here, we...
Source: Journal of Biomechanical Engineering - January 18, 2019 Category: Biomedical Engineering Source Type: research

Multidirection Validation of a Finite Element 50th Percentile Male Hybrid III Anthropomorphic Test Device for Spaceflight Applications
The objective of this study was to validate a Hybrid III ATD FE model using a multidirection test matrix for future spaceflight configurations. Twenty-five Hybrid III physical tests were simulated using a 50th percentile male Hybrid III FE model. The sled acceleration pulses were approximately half-sine shaped, and can be described as a combination of peak acceleration and time to reach peak (rise time). The range of peak accelerations was 10 –20 G, and the rise times were 30–110 ms. Test directions were frontal (−GX), rear (GX), vertical (GZ), and lateral (GY). Simulation responses were compared to physical tests ...
Source: Journal of Biomechanical Engineering - January 18, 2019 Category: Biomedical Engineering Source Type: research

The Effect of Textiles Impregnated With Particles With High Emissivity in the Far Infrared, on the Temperature of the Cold Hand
In engineering and medicine, there is a growing interest in using textiles made of composites with enhanced thermal properties. One such type of textile is fabric impregnated with ceramics and mineral particles. This material has high emissivity in the infrared range and may have therapeutic benefits for treatments of diseases, like Raynaud's syndrome. While there is significant clinical and commercial interest, there is an evident lack of fundamental studies on the heat transfer aspects of these fabrics. The goal of this technical brief is to present results from a fundamental study examining the thermal effects of fabric...
Source: Journal of Biomechanical Engineering - January 18, 2019 Category: Biomedical Engineering Source Type: research

The Effect of Inhomogeneous Trabecular Stiffness Relationship Selection on Finite Element Outcomes for Shoulder Arthroplasty
In conclusion, the low varia tions attributable to the selection of a trabecular stiffness relationship based on anatomic-site suggest that FE models constructed for shoulder arthroplasty can utilize an inhomogeneous site-pooled trabecular relationship without inducing marked variability in the assessed outcome measures. (Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - January 18, 2019 Category: Biomedical Engineering Source Type: research

Elastic Fiber Fragmentation Increases Transmural Hydraulic Conductance and Solute Transport in Mouse Arteries
Transmural advective transport of solute and fluid was investigated in mouse carotid arteries with either a genetic knockout of fibulin-5 (Fbln5−/−) or treatment with elastase to determine the influence of a disrupted elastic fiber matrix on wall transport properties. Fibulin-5 is an important director of elastic fiber assembly. Arteries from Fbln5−/− mice have a loose, noncontinuous elastic fiber network and were hypothesized to have reduced resistance to advective transport. Experiments were carried out ex vivo at physiological pressure and axial stretch. Hydraulic conductance (LP) was measured to be 4.99 ×�...
Source: Journal of Biomechanical Engineering - December 19, 2018 Category: Biomedical Engineering Source Type: research

Mesh Sensitivity Analysis for Quantitative Shear Stress Assessment in Blood Pumps Using Computational Fluid Dynamics
This study investigated the necessary mesh refinement to quantify shear stress for two selected, meshing sensitive hotspots within a rotary centrifugal blood pump (the blade leading edge and tip clearance gap). The shear stress in these regions is elevated due to presence of stagnation points and the flow around a sharp edge. The nondimensional mesh characteristic number y+, which is known in the context of turbulence modeling, underestimated the maximum wall shear stress by 60% on average with the recommended value of 1, but was found to be exact below 0.1. To evaluate the meshing related error on the numerical hemolysis ...
Source: Journal of Biomechanical Engineering - December 12, 2018 Category: Biomedical Engineering Source Type: research

Effects of Elastase Digestion on the Murine Vaginal Wall Biaxial Mechanical Response
Although the underlying mechanisms of pelvic organ prolapse (POP) remain unknown, disruption of elastic fiber metabolism within the vaginal wall extracellular matrix (ECM) has been highly implicated. It has been hypothesized that elastic fiber fragmentation correlates to decreased structural integrity and increased risk of prolapse; however, the mechanisms by which elastic fiber damage may contribute to prolapse are poorly understood. Furthermore, the role of elastic fibers in normal vaginal wall mechanics has not been fully ascertained. Therefore, the objective of this study is to investigate the contribution of elastic f...
Source: Journal of Biomechanical Engineering - December 12, 2018 Category: Biomedical Engineering Source Type: research