Article révisé par les pairs
Résumé : Native subject-specific knee geometries are usually based on CT and MRI images reconstruction. Unfortunately, while the definition of bone geometries using CTs is quite consistent, MRIs are often hardly readable, due to the usual lower resolution, and the final shape of cartilage and menisci is not consequently detailed enough. Moreover, further smoothing techniques, necessary to efficiently use these structures for numerical modeling, could result in bad interfaces and/or geometry inaccuracies. In this study a CAD-based approach to generate 3D cartilages and menisci geometries, avoiding the use of MRIs, was proposed and tested versus the traditional methods that use MRIs segmentation. The femoral, tibial and patellar cartilage layers were generated as offset from the bone geometries, the menisci were obtained by an extrusion based on tibia borders. Such geometries were compared to the reconstructions obtained from MRIs of healthy knee specimens. Overlapping the resulting geometries with the ones traditionally reconstructed, volumes differ from 2% to 14%. By using the new methodology, the geometries are obtained in 75% less time. The CAD-based methods shown in this pilot study is able to generate faster and accurate subject-specific knee cartilage layers and menisci geometries and can be suitable to be applied for numerical modeling.