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.

Appropriate Objective Functions for Quantifying Iris Mechanical Properties Using Inverse Finite Element Modeling
In this study, we have evaluated five different objective functions chosen based on the iris biometrics (in the presence and absence of clinical measurement errors) to determine the appropriate criterion for inverse modeling. Our results showed that in the absence of experimental measurement error, a combination of iris CL and CV can be used as the objective function. However, with the addition of measurement errors, the objective functions that employ a large number of local displacement values provide more reliable outcomes. (Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - April 30, 2018 Category: Biomedical Engineering Source Type: research

Quantitative Analysis of Tissue Damage Evolution in Porcine Liver With Interrupted Mechanical Testing Under Tension, Compression, and Shear
This study provides a foundation for future structure-based constitutive material modeling that can capture and predict the stress-state dependent damage evolution in liver tissue. (Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - April 30, 2018 Category: Biomedical Engineering Source Type: research

Hip Joint Contact Pressure Distribution During Pavlik Harness Treatment of an Infant Hip: A Patient-Specific Finite Element Model
In this study, CCP in a cartilaginous infant hip was investigated through patient-specific finite element (FE) modeling. We simulated CCP of the hip equilibrated at 90  deg flexion at abduction angles of 40 deg, 60 deg, and 80 deg. We found that CCP was predominantly distributed on the anterior and posterior acetabulum, leaving the superior acetabulum (mainly superolateral) unloaded. From a mechanobiological perspective, hypothesizing that excessive pressu re inhibits growth, our results qualitatively predicted increased obliquity and deepening of the acetabulum under such CCP distribution. This is the desired and ...
Source: Journal of Biomechanical Engineering - April 30, 2018 Category: Biomedical Engineering Source Type: research

Characterizing the HeartMate II Left Ventricular Assist Device Outflow Using Particle Image Velocimetry
Ventricular assist devices (VADs) are implanted in patients with a diseased ventricle to maintain peripheral perfusion as a bridge-to-transplant or as destination therapy. However, some patients with continuous flow VADs (e.g., HeartMate II (HMII)) have experienced gastrointestinal (GI) bleeding, in part caused by the proteolytic cleavage or mechanical destruction of von Willebrand factor (vWF), a clotting glycoprotein. in vitro studies were performed to measure the flow located within the HMII outlet cannula under both steady and physiological conditions using particle image velocimetry (PIV). Under steady flow, a mock fl...
Source: Journal of Biomechanical Engineering - April 30, 2018 Category: Biomedical Engineering Source Type: research

Assessment of Mechanical Characteristics of Ankle-Foot Orthoses
Recent designs of ankle-foot orthoses (AFOs) have been influenced by the increasing demand for higher function from active individuals. The biomechanical function of the individual and device is dependent upon the underlying mechanical characteristics of the AFO. Prior mechanical testing of AFOs has primarily focused on rotational stiffness to provide insight into expected functional outcomes; mechanical characteristics pertaining to energy storage and release have not yet been investigated. A pseudostatic bench testing method is introduced to characterize compressive stiffness, device deflection, and motion of solid-ankle...
Source: Journal of Biomechanical Engineering - April 30, 2018 Category: Biomedical Engineering Source Type: research

Beneficial Effects of Exercise on Subendothelial Matrix Stiffness are Short-Lived
Aerobic exercise helps to maintain cardiovascular health in part by mitigating age-induced arterial stiffening. However, the long-term effects of exercise regimens on aortic stiffness remain unknown, especially in the intimal extracellular matrix layer known as the subendothelial matrix. To examine how the stiffness of the subendothelial matrix changes following exercise cessation, mice were exposed to an 8 week swimming regimen followed by an 8 week sedentary rest period. Whole vessel and subendothelial matrix stiffness were measured after both the exercise and rest periods. After swimming, whole vessel and subendothelial...
Source: Journal of Biomechanical Engineering - April 19, 2018 Category: Biomedical Engineering Source Type: research

Biomechanical Effects on Cervical Spinal Cord and Nerve Root Following Laminoplasty for Ossification of the Posterior Longitudinal Ligament in the Cervical Spine: A Comparison Between Open-Door and Double-Door Laminoplasty Using Finite Element Analysis
Many clinical case series have reported the predisposing factors for C5 palsy and have presented comparisons of the two types of laminoplasty. However, there have been no biomechanical studies focusing on cervical spinal cord and nerve root following laminoplasty. The purpose of this study is to investigate biomechanical changes in the spinal cord and nerve roots following the two most common types of laminoplasty, open-door and double-door laminoplasty, for cervical ossification of the posterior longitudinal ligament (OPLL). A finite element (FE) model of the cervical spine and spinal cord with nerve root complex structur...
Source: Journal of Biomechanical Engineering - April 19, 2018 Category: Biomedical Engineering Source Type: research

Influence of the Musculotendon Dynamics on the Muscle Force-Sharing Problem of the Shoulder —A Fully Inverse Dynamics Approach
In conclusion, for slow-speed, standard movements of the upper limb, as those studied here, the activation and musculotendon contraction dynamics can be neglected in inverse dynamic analyses without compromising the prediction of muscle and joint reaction forces. (Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - April 19, 2018 Category: Biomedical Engineering Source Type: research

Material Properties of Rat Middle Cerebral Arteries at High Strain Rates
Traumatic brain injury (TBI), resulting from either impact- or nonimpact blast-related mechanisms, is a devastating cause of death and disability. The cerebral blood vessels, which provide critical support for brain tissue in both health and disease, are commonly injured in TBI. However, little is known about how vessels respond to traumatic loading, particularly at rates relevant to blast. To better understand vessel responses to trauma, the objective of this project was to characterize the high-rate response of passive cerebral arteries. Rat middle cerebral arteries (MCAs) were isolated and subjected to high-rate deforma...
Source: Journal of Biomechanical Engineering - April 19, 2018 Category: Biomedical Engineering Source Type: research

Assessment of the Effectiveness of Combat Eyewear Protection Against Blast Overpressure
It is unclear whether combat eyewear used by U. S. Service members is protective against blast overpressures (BOPs) caused by explosive devices. Here, we investigated the mechanisms by which BOP bypasses eyewear and increases eye surface pressure. We performed experiments and developed three-dimensional (3D) finite element (FE) models of a head form (HF) equipped with an advanced combat helmet (ACH) and with no eyewear, spectacles, or goggles in a shock tube at three BOPs and five head orientations relative to the blast wave. Overall, we observed good agreement between experimental and computational results, with average d...
Source: Journal of Biomechanical Engineering - April 19, 2018 Category: Biomedical Engineering Source Type: research

Properties of the Temporomandibular Joint in Growing Pigs
A subset of temporomandibular joint (TMJ) disorders is attributed to joint degeneration. The pig has been considered the preferred in vivo model for the evaluation of potential therapies for TMJ disorders, and practical considerations such as cost and husbandry issues have favored the use of young, skeletally immature animals. However, the effect of growth on the biochemical and biomechanical properties of the TMJ disk and articulating cartilage has not been examined. The present study investigates the effect of age on the biochemical and biomechanical properties of healthy porcine TMJs at 3, 6, and 9 months of age. DNA, h...
Source: Journal of Biomechanical Engineering - April 19, 2018 Category: Biomedical Engineering Source Type: research

Simulation of Airflow in an Idealized Emphysematous Human Acinus
Emphysema is the permanent enlargement of air spaces in the respiratory regions of the lung due to destruction of the inter-alveolar septa. The progressive coalescence of alveoli and alveolar ducts into larger airspaces leads to the disruption of normal airway wall motion and airflow rates within the pulmonary acinus. To contribute to the understanding of the individual effects of emphysema during its earliest stages, computational fluid dynamics (CFD) simulations of airflow in mathematically derived models of the pulmonary acinus were performed. The here generated computational domain consists of two generations of alveol...
Source: Journal of Biomechanical Engineering - April 19, 2018 Category: Biomedical Engineering Source Type: research

Applying a Hybrid Experimental-Computational Technique to Study Elbow Joint Ligamentous Stabilizers
(Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - April 4, 2018 Category: Biomedical Engineering Source Type: research

Frontal Plane Tibiofemoral Alignment is Strongly Related to Compartmental Knee Joint Contact Forces and Muscle Control Strategies During Stair Ascent
(Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - April 4, 2018 Category: Biomedical Engineering Source Type: research

A Uniaxial Testing Approach for Consistent Failure in Vascular Tissues
(Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - April 4, 2018 Category: Biomedical Engineering Source Type: research