1. Center for Orthopedics, Trauma Surgery and Paraplegiology, Clinic for Orthopedics and Trauma Surgery, University Hospital Heidelberg, Heidelberg, Germany.
2. Tissue Engineering, VA Boston Healthcare System, Boston, Massachusetts.
3. Department of Orthopedic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
4. Division of Nuclear Medicine and Molecular Imaging, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
5. Department of Nuclear Medicine, University Hospital Heidelberg, Heidelberg, Germany.