Finite element analysis of acetabular fractures--development and validation with a synthetic pelvis.

Acetabular fracture presents a challenging situation to trauma surgeons today due to its complexity. Finite element (FE) models can be of great help as they can improve the surgical planning and post surgery patient management for those with acetabular fractures. We have developed a non-linear finite element model of the pelvis and validated its fracture prediction capability with synthetic polyurethane pelves. A mechanical experiment was performed with the synthetic bones and fracture loads and patterns were observed for two different loading cases. Fracture loads predicted by our FE model were within one standard deviation of the experimental fracture loads for both loading cases. The incipient fracture pattern predicted by the model also resembled the actual pattern from the experiment. Although it is not a complete validation with human cadaver bones, the good agreement between model predictions and experimental results indicate the validity of our approach in using non-linear FE formulation along with contact conditions in predicting bone fractures.

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