A new method to track the deformation of the trabecular structure in a human bone, which determines the dynamic characteristics of bone, was developed using elastic matching. This is a kind of image analysis. By comparing two 3-D images of the same bone taken at different times, this method computes displacement of any points in the bone during the period. This method makes it possible to demonstrate the behavior of the trabecular structure to mechanical loads and to estimate changes in the strength of a bone.