Said T Gomaa

DePuy Synthes · Research

An orthopaedic knee prosthesis includes a femoral component having a condyle surface. The condyle surface is defined by one or more radii of curvatures, which are controlled to reduce or delay the onset of anterior translation of the femoral component relative to a tibial bearing.

A customized patient-specific orthopaedic surgical system including a first surgical block, a second surgical block, and a computer-controlled milling machine. The first surgical block includes a first bone-facing surface having a first customized patient-specific negative contour to receive a first corresponding contour of a bone of a patient and...

Computational mechanics methods, such as finite element analysis or multibody dynamics, are usually employed toward the end of the design phase of a total joint implant system. It is of greater benefit, however, to utilize these methods early in the design process as a benchmarking tool to compare competitive products, as a screening tool to elimin...

Computational mechanics methods, such as finite element analysis or multibody dynamics, are usually employed toward the end of the design phase of a total joint implant system. It is of greater benefit, however, to utilize these methods early in the design process as a benchmarking tool to compare competitive products, as a screening tool to elimin...

Enhancements to the service life and performance of orthopedic implants used in total knee and hip replacement procedures can be achieved through optimization of design and the development of superior biocompatible polymeric materials. The introduction of a new or modified polymer must, naturally, be preceded by a rigorous testing program. This pap...

Paradoxical anterior translation has been reported to occur to varying degrees in total knee replacement devices. Although it has been observed in most fluoroscopic studies of posterior cruciate retaining devices, is not clear what design attributes might be contributing to this undesirable kinematic outcome. We compared simulations of a double leg...

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

This computational study examines a rotating-platform TKA design in a weight-bearing functional activity (deep knee bending) to explore theoretical differences in wear-related contact parameters page 162 ISBN: 978-84-691-2464-2

The paper describes recent research conducted at Rensselaer aimed at modeling and simulation of failure processes in composite materials and structures using micromechanical and macromechanical approaches. The micromechanical approach is based on the mathematical homogenization theory with eigenstrains and a rapid post-processing procedure, which e...

The isotropic, unified state variable theory based on overstress consisting of a flow law and two tensor-valued and two scalar-valued stress-like state variables is extended to finite deformation. To this end the Cauchy stress rate and the rates of the two tensor-valued state variables are interpreted as Eulerian tensors. Their objective rates are...

This thesis is dedicated to developing the computational procedures required in implementing the finite element method for finite deformation, rate-independent plasticity and finite deformation viscoplasticity theory based on overstress. The classical rate-independent, von Mises plasticity is formulated using both hypoelastic-plastic model and hype...

SUMMARY An accelerated multigrid method, which exploits shell element formulation to speed up the iterative process, is developed for inherently poor conditioned thin domain problems on unstructured grids. Its building blocks are: (i) intergrid transfer operators based on the shell element shape functions, (ii) heavy smoothing procedures in the for...

This paper presents recent research efforts at Rensselaer Polytechnic Institute aimed at developing computer-aided multiscale modeling tools for composite materials and structures aimed at predicting the macromechanical (overall) structural response, such as critical deformation, vibration and buckling modes, as well as various failure modes on the...

A finite element formulation for flexure of deep beams based on a recent refined theory is developed. The refined theory incorporates effects of transverse shear, transverse normal stress and transverse normal strain. The Galerkin finite element method was used to develop the finite element equations for both beam bending and in-plane problems. The...

A finite element formulation for flexure of isotropic plates based on a recent refined theory is developed. The refined theory incorporates effects of transverse shear, transverse normal stress and transverse normal strain. The Galerkin finite element method was used to develop the finite element equations for both plate bending and inplane problem...