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Abstract
Purpose
The goal of this study using the biomechanical test was to evaluate the mechanical stability of the bone-plate fixation system according to changes of the fracture gap sizes and widths.
Materials and Methods
For mechanical test, four types with different fracture models simulating the clinical situations were constructed depending on the gap size (FGS, mm) and the gap width (FGW, %) at the fracture site: 0 mm/0%, 1 mm/100%, 4 mm/100%, 4 mm/50%. For analyzing the effects of fracture gap on the biomechanical stability of the bone-plate fixation system, 4-point bending test was performed under all same conditions.
Results
It was found that the fracture gap sizes of 1 and 4 mm decreased mechanical stiffness by about 50~60% or more. Furthermore, even without fracture gap size, 50% or more fracture gap width considerably decreased mechanical stiffness and suggested the possibility of plate damage through strain results.
Figures and Tables
Figure 1
The LC-DCP bone fixation system and the epoxy pipe represented as a bone (A) and specimen configurations (B) for the fracture gap sizes & width (mm/%).
Figure 2
Mechanical experiment through 4-pont bending test (A→B→D→C) with LC-DCP bone- plate fixation system.
Figure 3
Determination of the initial and final bending stiffness (Nm/°) with the bending moment (Nm)-bending angle (°) curve.
Figure 4
Comparison of bending moments according to the fracture gap sizes and widths on the LC-DCP fixation system.
Figure 5
Comparison of the initial and final bending stiffness (Nm/°) according to the fracture gap sizes and widths of LC-DCP: *indicates significant difference compared with 0 mm/0% model in the initial stiffness.
References
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