Análise estrutural de uma placa de osteossíntese em fraturas de Hoffa utilizando o método dos elementos finitos (MEF)

Abstract

The development of new medical orthotics for the treatment of fractured bones requires tools that are versatile to test different cases and that are economically viable. The use of virtual simulations, as in structural simulation software, which are based on the Finite Element Method (FEM) analysis, is very advantageous because it fulfills these requirements, in addition to dispensing with the execution of entirely physical tests. There is a medical interest to test internal fixations, which are a type of orthosis, in femoral fractures in the region of the condyles, where there is the knee joint, also known as Hoffa fracture, as an orthosis that guarantees better fixation of the broken parts would mean in better patient recovery. Bone is an anisotropic and heterogeneous material, with regions of greater and lesser rigidity, in addition to having special properties such as viscoelasticity and creep. For coronal fractures in the region of the femoral condyles, the Letenneur classification is of three types: I, II and III. A static structural simulation to evaluate the application of an orthosis must assign material properties consistent with the bone, in addition to having adequate mesh, boundary conditions to model the problem in question. The present study aims to simulate an internal fixation of an “H”-shaped plate with screws in Hoffa fractures considering the three types according to the Letenneur classification, using CAD and CAE engineering software. With the results obtained, it was possible to conclude that the H-plate showed better fixation for Hoffa type III fractures, in addition to serving as a validation to justify the realization of real physical tests, and possibly, in the future, a test with humans.