1. Center for Molecular Orthopaedics, Harvard Medical School, Boston, Massachusetts.
2. Department of Rheumatology, New York University Medical School, New York.
3. Department of Orthopaedic Surgery, University of Graz Medical School, Graz, Austria.
4. Department of Orthopaedics and Rehabilitation, University of Florida College of Medicine, Gainesville, Florida.
5. Department of Orthopaedic Surgery, University of Wüerzburg Medical School, Wüerzburg, Germany.