文档介绍：Developing a Consistent Method for Evaluating
Orthopaedic Hip Implants
Frank Murphy
Kx Simulation Technologies, Inc.
Paul R. Tomaszewski
DePuy Orthopaedics, Inc.
Abstract
This paper describes the purpose, evolution and implementation of a custom user interface for the analysis
of orthopaedic [artificial] hip stem designs.
The orthopaedic implant industry is regulated by the . Food and Drug Administration [FDA]. Thorough
testing procedures are necessary before an implant is approved for general use. Typically, this involves a
variety of physical and analytical assessments including the determination of sustainable bending stresses
in a particular hip stem and the corresponding peak load-carrying capacity. Ultimately, a physical prototype
is fatigue tested and will be released only after passing all required tests.
bination of closed-form textbook solutions, often in spreadsheet format, has often been used for
initial evaluations. The difficulties and dangers in this approach are manifold and monly cited: they
include poorly understood and inappropriately applied formulas, as well as the limited nature of the
resulting data. Despite these hazards, up-front analysis of each hip stem design is necessary to reduce the
number of prototypes that are manufactured and tested. The ability to plete the analysis phase
of any process is critical to shorten design cycles. A customized solution was needed which would work
within the context of the current finite element tools to provide reliable design information directly to the
designers.
This was plished by writing a UIDL-based “wrapper”[User Interface Design Language] for ANSYS
[Canonsburg, PA] simulation software. It guides the user through a series of input screens for the selection
and analysis of a variety mon hip stem evaluations. Through the use of drop-down menus, engineers
are limited to evaluations that make sense for their particular product family.
In a con