This project is a feasibility study for the analysis of the variation in shape of knee bone structures of patients with different severities of osteoarthritis. The major goal is to identify characteristic knee joint geometries for different arthritic stages in order to provide a geometric foundation for the design of elastic spacers that are to be inserted into the joint gap of arthritic patients. For this study data from the OAI database has been selected. Knee bone structures are segmented from MRI data and bony anatomy is geometrically reconstructed in order to perform a preliminary cluster analysis in 3d shape space. Results of the project are to be used in a larger scale analysis for the design of a suitable set of interpositional spacers.