Abstract:

BACKGROUND: Currently, most of biomechanical research about internal fixation of patellar fracture has been carried out by corpse. Few researchers carried out it using modern finite element method.
OBJECTIVE: To establish the finite element model of patella fracture fixed with AO tensile force girdle and to perfore finite element mechano-analysis.
METHODS: An adult female volunteer was selected, underwent a lamellar computed tomography (CT) scan on the lower extremity, extract right patella’s polylines by Mimics10.01 software and construct geometrical models. Then the geometrical model was imported into PRO/E 2.0 software, to simulate bone fracture by intersected function of PRO/E 2.0 software and generate two bent Kirschner wires and annular steel-wire, rebuild 3D model of patella fracture fixed with AO tensile force girdle. After that, the model was imported into the ANSYS software to constructe 3D finite-element models that analyzing displacement and deformation features simulating patellofemoral joint under 600 N loading at 90° knee bending.  
RESULTS AND CONCLUSION: The AO tensile force girdle could force patella fracture in many ways, and opposed to tensile force of musculus quadriceps fexoris. The finite element analytic result coincides with biomechanical result. The 3D finite-element model of patella fracture fixed with AO tensile force girdle was scientific, which is beneficial to better understanding of the biomechanical principle about patella fracture fixed with AO tensile force girdle and provides clinical instruction.