Abstract
This study aimed to develop in vivo six-degree-of-freedom (6-DOF) motion analysis for a natural knee joint with high precision using an image matching technique with high-resolution X-ray images from a flat panel detector (FPD). The image matching technique was performed determining the strength of a correlation between X-ray images and computational simulating images. However, the number of pixels in a whole reconstructed image was so huge. Therefore, in this study, several windows were set up, in which a region of interest was determined to calculate instead of viewing the whole region of the image. The computational simulating image was created by the three-dimensional gray-scale model reconstructed using computed tomography (CT) images. We report the results of a motion pattern in analysis for natural knee joints in stair-climbing activity using the developed method.