Finite Element Analysis of Implant Fixation Strength
Implant fixation is critical for long-term survival of orthopaedic joint replacements. Fixation strength is typically assessed in animal studies, which are costly, and provide only limited insight into failure of fixation. This study supplements animal studies with computational analysis of implant fixation strength. MicroCT scans of implants and bones are segmented in MATLAB and used to create finite element models of the implant/bone interface. Abaqus is then used to simulate a pushout-test used to determine implant fixation strength, and the results are compared to physical test results. Once the simulations have been validated, further analyses are performed to test fixation strength under different loading conditions. MATLAB code has also been written to generate variants of trabecular arrangements around implants, to determine the effect of trabecular bone morphology on the resultant fixation strength. The goal of this project is to gain insight into the factors (bone volume, trabecular arrangement, bone properties, etc.) that most influence fixation strength, and use that insight to guide future implant development and surgical technique.