La geometría de la quilla condiciona el comportamiento de la bandeja tibial frente a fuerzas de torsión en prótesis totales de rodilla / The geometry of the keel determines the behaviour of the tibial tray against torsional forces in total knee replacement

El diseño de la quilla de una bandeja tibial es fundamental para la transmisión de la mayor parte de las cargas a las estructuras óseas periféricas, las cuales tienen mejores propiedades mecánicas reduciendo, de este modo, el riesgo de aflojamiento. El objetivo de este estudio es comparar el comportamiento de diferentes diseños de bandeja tibial ante cargas de torsión. Se modelizaron 4 componentes tibiales diferentes. La reconstrucción 3 D se llevó a cabo con el programa MIMICS. Los sólidos se generaron en SolidWorks. Se realizó el estudio por elementos finitos mediante Unigraphics. Se simuló una torsión de 6 Nm aplicada sobre los laterales de cada bandeja tibial. La bandeja tibial GENUTECH® con apoyo en el hueso trabecular periférico mostró un menor desplazamiento y menores tensiones transmitidos bajo fuerzas de torsión. Los resultados indican que la bandeja tibial con apoyo más periférico tienen un mejor comportamiento mecánico mejor frente a los otros diseños estudiados (AU)

The keel design of the tibial tray is essential for the transmission of the majority of the forces to the peripheral bone structures, which have better mechanical proprieties, thus reducing the risk of loosening. The aim of the present study was to compare the behaviour of different tibial tray designs submitted to torsional forces. Four different tibial components were modelled. The 3-D reconstruction was made using the Mimics software. The solid elements were generated by SolidWorks. The finite elements study was done by Unigraphics. A torsional force of 6 Nm. applied to the lateral aspects of each tibial tray was simulated. The GENUTECH® tibial tray, with peripheral trabecular bone support, showed a lower displacement and less transmitted tensions under torsional forces. The results suggest that a tibial tray with more peripheral support behaves mechanically better than the other studied designs (AU)

[The geometry of the keel determines the behaviour of the tibial tray against torsional forces in total knee replacement]. / La geometría de la quilla condiciona el comportamiento de la bandeja tibial frente a fuerzas de torsión en prótesis totales de rodilla.

The keel design of the tibial tray is essential for the transmission of the majority of the forces to the peripheral bone structures, which have better mechanical proprieties, thus reducing the risk of loosening. The aim of the present study was to compare the behaviour of different tibial tray designs submitted to torsional forces. Four different tibial components were modelled. The 3-D reconstruction was made using the Mimics software. The solid elements were generated by SolidWorks. The finite elements study was done by Unigraphics. A torsional force of 6 Nm. applied to the lateral aspects of each tibial tray was simulated. The GENUTECH® tibial tray, with peripheral trabecular bone support, showed a lower displacement and less transmitted tensions under torsional forces. The results suggest that a tibial tray with more peripheral support behaves mechanically better than the other studied designs.