Geometric modeling and multi-axis NC machining for custom-made femoral stem

In this paper, a design system combining clinical experience and engineering knowledge was developed for the manufacture of custom-made femoral stem. The medical image of the hip obtained according to the patient X-rays. The geometric parameters for femoral stem were established based on the canal flare index. The necessary constrains based on surgical experience were integrated into the CAD system. The rapid prototyped model was built as the reference for review. Through the application of CAM software, the interference-free toolpath and the cutter location for multi-axis NC machining are generated. In order to establish the interface between the design and the manufacture of femoral stem, the postprocessor for multi-axis machine tool is developed. The cutting simulations with solid model are performed to verify the generated toolpath. It is also verified through the trial-cut with model material on a five-axis machine tool.