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A comparative study of uncemented tibial components.

P S Walker·H P Hsu·R A Zimmerman
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Abstract

The effect of tibial component stem and post design on load distribution and on displacements at the component-bone interface was investigated. Four different configurations were tested with a flat component used as a control. Loading conditions included vertical central, vertical offset (eg, varus/valgus), shear and torque. Both artificial and cadaveric bones were used in the study. Pressure-sensitive film was used to obtain pressure patterns at the interface. Image processing was then used to quantify the load distribution. For shear and torque, relative motion was seen as a smeared pressure pattern. This was calibrated in terms of microns of displacement as a function of image density. The central stemmed and bladed designs performed better than short-pegged designs, in resistance to offset loading. In shear and torque, short pegs close to the component periphery, or a central stem with blades, produced the least interface displacement. The application of this work to the design of components for both press-fit and cemented application is discussed.

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CementationHumansIn Vitro TechniquesKnee JointKnee ProsthesisProsthesis DesignStress, MechanicalTibiaComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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P S Walker, H P Hsu, R A Zimmerman. 1990. A comparative study of uncemented tibial components.. https://doi.org/10.1016/s0883-5403(08)80079-4

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