Investigate of the influence of pin deviation on the biomechanical environment of fixator-bone system by finite element method

Unilateral external fixators are widely used in orthopedics to stabilize fractured bones and in the treatment of limb deformities. Vivo mechanical environment inside and around the fixator may influence the healing of fractured bone. Due to the existence of pin deviation may affect biomechanical environment of callus in the fracture gap. Finite element analysis was used to investigating stress and deformation of fixator-bone system under axial load, torsional load and bending load, comparing the biomechanical properties of two fixator structures: the one has pin deviation angle, the other has no pin deviation angle. These results reveal that the existence of pin deviation would affect the biomechanical environment of fractured bone. When fixator-bone system under three kinds of load, the stress and deformation of fixator-bone system were greater than that of fixator-bone system without pin deviation. This work provides orthopedics doctor useful information to predict the micromovements of fixator-bone system.