1. Department of Orthopedics Balgrist University Hospital University of Zurich Lengghalde 5 Zurich 8008 Switzerland
2. Institute for Biomechanics ETH Zurich Zurich 8093 Switzerland
3. Center of Experimental Rheumatology Department of Rheumatology University Hospital, University of Zurich Lengghalde 5 Zurich 8008 Switzerland
4. Fraunhofer Institute for Cell Therapy and Immunology 04103 Leipzig Germany