Structural analysis of the main fixation elements of the apparatus for external osteosynthesis

In order to determine the degree of stability of osteosynthesis, four basic fixation systems have been identified. These principles are based on the interaction of the fixator and bone fragments. 1. Fixator-bone, this part of the element is directly connected to a bone. 2. Intermediate fragment, this is the space between the bone and the supporting part of the retainer. 3. Fixator-fixator, this level concerns the assembly in general. 4. The bone-bone through the fixator. In this paper, the main methods and approaches of structural mechanics that can be applied to the analysis of the first fixation level, i.e. fixator-bone are used. These methods can be used to select the components of the external fixation device providing the required stiffness and strength of the apparatus. The calculation schemes and constitutive equations to calculate stress-strain state of the apparatus elements providing its attachment to the bone are given. Based on the calculations results, graphs and tables for selecting external fixator elements are presented, and the deformation of the components is shown.