Artificial Joint Surface Fitting Based on Moving Least Squares Methods

Due to knees joint structure multiformity and complexity, people still lack effective means to get precise data and reconstruct three-dimensional model for custom-made knee joint prosthesis design. To solve the problem, this paper has put forward an innovative reverse engineering application for the reconstruction of the knee joint. Given the two-dimensional image through CT scanning, using image processing and reconstruction techniques, the contour curves of slice images were obtained, then a new slice curve between two neighbor slice was concluded by three dimensional moving least square fitting methods. Based on the intensified data of slice curves, we could produce the model by triangulation process; the surface of the model was smoother because the high weight function was adopted by the moving least squares. Exactly geometric parameter and model of knee joint have been obtained through the study of CT images processing, reverse engineering and its surface fitting. It has achieved the goals to help the doctor to diagnose knee joint and other medical operation.