Abstract
Purpose
We wanted to evaluate the mechanical strength of proximal tibia as resection distance increased from the joint surface.
Materials and Methods
We obtained the CT images of twenty knee osteoarthritis patients undergoing total knee arthroplasty. The finite element models were created based on the computed tomography images. The 8-node hexahedron element was made from BIONIX™ (CANTIBio. Co, Suwon, Korea), which is automatic mesh generation software program. The finite element model of the proximal tibia was resected at 6 mm, 8 mm, 10 mm, 12 mm, 15 mm and 18 mm from the lateral joint surface. A 1% strain rate was applied to a model by using HyperMesh™ software (Altair Engineering. Inc, Seattle, USA). The ultimate stress was calculated from the finite element analysis with using ANSYS 9.0 (ANSYS. Inc, Orlando, USA).
Results
The mean ultimate stress was 906.84 MPa, 877.22 MPa, 895.93 Mpa, 852.70 MPa, 742.90 Mpa and 585.51 Mpa at the 6 mm, 8 mm, 10 mm, 12 mm, 15 mm and 18 mm resection levels. As compare to the 6 mm resection level, the bone strengths at 15 mm and 18 mm were decreased with statistical significance (15 mm: p=0.005, 18 mm: p=0.000).
Figures and Tables
References
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