RÉSUMÉ
Objective To establish CT image-based, three-dimensional finite element models of healthy tibiae and plateau-fracture tibiae, and to calculate the displacement and stress distribution of the tibial models .Methods Continuous-time tomographic images of knee joints of a healthy adult and a patient with tibial plateau fractures were obtained using multi-slice spiral CT scan , and inputed to Mimics to establish three-dimensional surface mesh models of tibiae .The models underwent global meshing procedures and material properties assignment to construct finite element models of normal and plateau-fracture tibiae in ANSYS , and the newly established models were analyzed and calculated .Results In case of applied load on the tibial plateau , the peak strains of the load-contact sites in the healthy subject and the patient presented divergent directions , with peak strains on the medial tibia in the healthy subject and lateral tibia in the patient , respectively . Equivalent stress decreased gradually down the tibiae and concentrated in the one -third of the upper and middle regions in both types of tibiae .Moreover, concentration of stress was also present in the locus of the fractured tibia .The deformation displacement gradients were more evident in the healthy tibia than in the fractured tibiae .There was significant difference in overall stress distribution between the two types of tibiae .Conclusion Three-dimensional finite element models of tibiae have been established that can demonstrate the differences in biomechanical properties between healthy and plateau -fracture tibiae, which might provide reference and guidance for orthopedic regimens .