A note on some identification problems arising in roentgen stereo photogrammetric analysis.

When studying skeleton movements by using implanted landmarks and Roentgen stereo photogrammetric analysis (RSA), some identification problems arise. One is to put the same label on a landmark at different examinations, another is to use the correct pairs of landmark images in order to compute a correct three-dimensional position of each landmark. We will present some methods that can be used as a support for solving these problems. We will also show how it is possible to detect and exclude landmarks that are loose and landmarks that have large measurement errors in their positions.