DETERMINING THE STABILITY OF NOVEL EXTERNAL FIXATOR BY USING MEASURING SYSTEM

Original scientific paper External fixators are used to treat open and closed fractures of long bones. Stiffness and strength of the fixator greatly affect the final outcome of treatment. An adequate stability of bone fragments provides better fracture healing and early rehabilitation of patients. The aim of this study was to evaluate biomechanical stability of the newly developed unilateral external fixator for proximal tibial fractures. In order to compare the properties of the prototype of the novel fixator and commonly used external fixator Orthofix, static and dynamic tests were conducted. Two different types of static tests were carried out, axial compression test and bending test. In static tests displacements were measured and calculated by using the non-contact optical measuring system Aramis. The results indicated that the novel fixator has better outcomes in bending, while the conventional fixator outperformed the new one in axial compression. There was no significant difference in cyclic test.

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