Simulation of physiological loading in total hip replacements.

A Ramos; F Fonseca; J A Simões

doi:10.1115/1.2205864

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PubMed · 16813449

Simulation of physiological loading in total hip replacements.

A Ramos·F Fonseca·J A Simões

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Abstract

The determination of biomechanical force systems of implanted femurs to obtain adequate strain measurements has been neglected in many published studies. Due to geometric alterations induced by surgery and those inherent to the design of the prosthesis, the loading system changes because the lever arms are modified. This paper discusses the determination of adequate loading of the implanted femur based on the intact femur-loading configuration. Four reconstructions with Lubinus SPII, Charnley Roundback, Muller Straight and Stanmore prostheses were used in the study. Pseudophysiologic and nonphysiologic implanted system forces were generated and assessed with finite element analysis. Using an equilibrium system of forces composed by the Fx (medially direction) component of the hip contact force and the bending moments Mx (median plane) and My (coronal plane) allowed adequate, pseudo-physiological loading of the implanted femur. We suggest that at least the bending moment at the coronal plane must be restored in the implanted femur-loading configuration.

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Computer Simulation Computer-Aided Design Elasticity Equipment Failure Analysis Femur Finite Element Analysis Hip Joint Hip Prosthesis Humans Models, Biological Prosthesis Design Stress, Mechanical Torque Weight-Bearing Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't

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A Ramos, F Fonseca, J A Simões. 2006. Simulation of physiological loading in total hip replacements.. https://doi.org/10.1115/1.2205864

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