The ability of surgeons to optimize screw insertion torque in nonlocking fixation constructs is important for stability, particularly osteoporotic and cancellous bone. This study evaluated applied by during synthetic fixation. It the frequency with which screws were stripped surgeons, factors associated stripping, recognize it.Ten assembled plate into 3 densities bone while axial force measured. For each screw, surgeon recorded a subjective rating as whether or not had been stripped. Screws...

Micro-Raman spectroscopy has been widely used to measure local stresses in silicon and other cubic materials. However, a single (scalar) line position measurement cannot determine the complete stress state unless it very simple form such as uniaxial. Previously published micro-Raman strategies designed additional elements of tensor take advantage polarization intensity Raman-scattered light, but these have not validated experimentally. In this work, we test one stategy [S. Narayanan, S....

The position, axis, and control of each lower extremity joint intimately affect adjacent function as well whole-limb performance. A review the literature finds little describing biomechanics subtalar arthrodesis effect on ankle biomechanics. purpose current study was to establish this sagittal plane biomechanics.A performed using a 3-dimensional, validated, computational model extremity. simulated from 20 degrees varus valgus. At dorsiflexor plantarflexor muscles' fiber force, moment arm,...

Background: Subtalar arthrodesis is a common treatment for end-stage subtalar joint arthritis as well many other clinical problems. The best method of fixation unknown. purpose this study was to compare the strength methods including single posterior screw (SP), 2 minimally divergent screws (MD) and highly (HD) construct arthrodesis. Methods: A biomechanical performed three different configurations (SP, MD, HD). These surrogate bone specimens were subjected applied inversion eversion torques...

Introduction: There are many screw and thread designs commercially available to surgeons for bone fixation. is a paucity of literature on comparative mechanical properties various including variable pitch screws, tapered screws. This purpose this study was test whether varying screws and/or tapering core diameter alters the performance Methods: A pullout performed 4 different designs, screw, constant variations these in straight design. Three-dimensional printing technology used manufacture...

A discrete cohesive zone method finite element is used to evaluate traction law efficiency and robustness in predicting decohesion a model.Three laws are reported compared from the perspective of their computational robustness.The smooth (based on beta distribution sine functions) found have greater than trapezoidal law.Efficiency gains due elimination stiffness discontinuities associated with generalized law.The sinusoidal be more robust efficient other laws.

The objective of this study is to evaluate whether real-time torque feedback may reduce the occurrence stripping when inserting nonlocking screws through fracture plates into synthetic cancellous bone.Five attending orthopaedic surgeons and 5 senior level residents inserted 8 in each phase. In phase I, were without simulating conventional techniques. II, driven with visual feedback. III, again Comparison these 3 phases respect screw insertion torque, surgeon rank, perception was used...

View Video Presentation: https://doi.org/10.2514/6.2022-2280.vid Multiscale micromechanics predictions have been made for the effective thermal conductivities and local fields a novel 3D woven composite protection system material. The Recursive Micromechanics approach, which enables models to call other (or themselves recursively) consider finer length scales, has employed. multiscale model uses recently developed version of High-Fidelity Generalized Method Cells theory at each three scales....

An experimental program to determine the mode I critical energy release rate (GIc) of T650/AFR-PE-4/FM680-1 material system is reported. Two forms GIc are determined over range 20 350 C, area method G a and inverse (G i). The value was found increase with increasing temperature. be very effective determining entire temperatures. Inverse modeling completed using finite element method, coupled novel Discrete Cohesive Zone Element, i crack advance in given specimen. described detail, as well...

Background Clinical studies purport an increase in internal rotation strength after transfer subscapularis deficient patients. The present study aimed to establish the biomechanics of a pectoralis major muscle for treatment insufficiency. Methods A computational was performed utilizing three-dimensional, validated, model upper extremity. modeled as three distinct components. Moments were calculated from combined force (active and passive) well moment arms each rotators throughout physiologic...

Cubitus varus is a challenging-to-treat complication following pediatric fractures of the elbow.2Barrett I.R. Bellemore M.C. Kwon Y.M. Cosmetic results supracondylar osteotomy for correction cubitus varus.J Pediatr Orthop. 1998; 18: 445-447PubMed Google Scholar This typically thought to occur secondary malunion fracture or uneven growth resulting in angulation.9Kawanishi Y. Miyake J. Kataoka T. Omori S. Sugamoto K. Yoshikawa H. et al.Does cause morphologic and alignment changes elbow...

<h3>BACKGROUND:</h3> Infant respiratory distress remains a significant problem worldwide, leading to more than one million neonatal deaths each year. The cost, maintenance, energy, and personnel required implement ventilators have proven be barrier in many resource-limited settings. To address these barriers, nonelectric bubble noninvasive positive pressure ventilation (NIV) device was developed. This study aims benchmark the performance of this NIV against commercially available...

An artificial convolutional neural network was created to efficiently mimic a micromechanics model, the High Fidelity Generalized Method of Cells, for use in multi-scale structural finite element analysis. The found quickly and accurately replicate stiffness predicted by model using 2D image an idealized representative volume fiber/matrix microstructure. long-term goal this work is apply methods predicting damage progression composite structure.

Multiscale micromechanics predictions have been made for effective thermal conductivities and local fields a novel three-dimensional woven composite protection system material. The multiscale recursive approach, which enables models to call other (or themselves recursively) consider finer length scales, has employed. model uses recently developed version of the high-fidelity generalized method cells theory at each three scales. results focus on impact microstructural geometry representation...

Abstract Micro-Raman spectroscopy is used to determine the multiaxial stress state in silicon wafers using a strategy proposed by Narayanan, et al. (J. Appl. Phys. 82, 2595–2602 (1997)) Previously, this was validated when subjected uniaxial laboratory frame (Harris, J. 96, 7195–7201 (2004)). In present work, have been analyzed that were biaxial states frame. The predicted curves for initially degenerate F2g peaks found fall within variability of measured curves. Stress ratios be predictable....

Abstract A bonded joint finite element (FE) for a symmetric double lap is developed that capable of predicting field quantities in the region. The hybrid method and incorporates features classical analytical numerical methods. stiffness load vector formulations have unique, dependent, non‐linear shape functions based on an solution. adaptive are formulated terms dimensionless mechanical fraction...

<h3>BACKGROUND:</h3> Neonatal respiratory distress results in &gt; 1 million annual deaths worldwide. Bubble CPAP is a simple, effective, and widely used therapy for infants distress. In low-resource settings, more advanced support limited by cost, technical expertise, sporadic electricity. We sought to develop safe, inexpensive, simple solution provide further these infants. <h3>METHODS:</h3> A standard bubble system was modified 2 levels of positive airway pressure (bi-level pressure)...

This paper reports an experimental program to establish a cohesive zone model for the T650/AFR-PE-4 (laminate) and FM680-1 (adhesive) system. The is based on four parameter characterization: in each mode, range of values critical energy release rate strength are computed from set results. Values determined over temperature 20–350°C. Owing limitations, two methods determining Mode I reported double cantilever beam test: area method inverse method. button peel stress test. II parameters by...