RESUMO
No hay consenso en el tratamiento de elección de los recambios protésicos de rodilla con defectos óseos severos. Las opciones son variadas, cada una con sus ventajas e inconvenientes. Los trabajos clínicos publicados tienen sus limitaciones en cuanto al número de pacientes y el poco seguimiento clínico. Se presenta un trabajo biomecánico con elementos finitos comparativo de 5 diseños de implantes tibiales: vástago recto, con offset con/sin suplemento y vainas con/sin vástago, para poder analizar el comportamiento tanto del hueso tibial como del material a lo largo del tiempo. Dentro de las limitaciones que presenta un modelo matemático hemos podido ver que los implantes con vástago recto producen el mayor valor de reabsorción ósea alrededor del vástago, mientras que la menor reabsorción ósea tiene lugar en el hueso de la diáfisis proximal. Las vainas metafisarias tibiales sin vástago producen una menor reabsorción ósea que el resto en el canal medular (AU)
The best management of severe bone defects following total knee replacement is still controversial. Metal augments, tantalum cones and porous tibial sleeves could help the surgeon to manage any type of bone loss, providing a stable and durable knee joint reconstruction. Five different types of prostheses have been analysed: one prosthesis with straight stem; two prostheses with offset stem, with and without supplement, and two prostheses with sleeves, with and without stem. The purpose of this study is to report a finite element study of revision knee tibial implants. The main objective was to analyse the tibial bone density changes and Von Misses tension changes following different tibial implant designs. In all cases, the bone density decreases in the proximal epiphysis and medullary channels, with a bone density increase also being predicted in the diaphysis and at the bone around the stems tips. The highest value of Von Misses stress has been obtained for the straight tibial stem, and the lowest for the stemless metaphyseal sleeves prosthesis (AU)
Assuntos
Feminino , Humanos , Masculino , Artroplastia do Joelho/instrumentação , Artroplastia do Joelho/métodos , Artroplastia do Joelho , Tíbia/fisiologia , Remodelação Óssea , Remodelação Óssea/imunologia , Remodelação Óssea/fisiologia , Próteses e Implantes , Reabsorção Óssea/diagnóstico , Reabsorção Óssea/fisiopatologia , Diáfises/fisiologia , Tomografia Computadorizada de Emissão/métodos , Osso e Ossos/fisiologia , Osso e Ossos , Densidade Óssea/fisiologiaRESUMO
The best management of severe bone defects following total knee replacement is still controversial. Metal augments, tantalum cones and porous tibial sleeves could help the surgeon to manage any type of bone loss, providing a stable and durable knee joint reconstruction. Five different types of prostheses have been analysed: one prosthesis with straight stem; two prostheses with offset stem, with and without supplement, and two prostheses with sleeves, with and without stem. The purpose of this study is to report a finite element study of revision knee tibial implants. The main objective was to analyse the tibial bone density changes and Von Misses tension changes following different tibial implant designs. In all cases, the bone density decreases in the proximal epiphysis and medullary channels, with a bone density increase also being predicted in the diaphysis and at the bone around the stems tips. The highest value of Von Misses stress has been obtained for the straight tibial stem, and the lowest for the stemless metaphyseal sleeves prosthesis.