1. Department of Anatomy and Cell Biology, Saarland University, D‑66421 Homburg/Saar, Germany
2. Department of Clinical and Experimental Surgery, Saarland University, D‑66421 Homburg/Saar, Germany
3. Department of Trauma, Hand and Reconstructive Surgery, Saarland University, D‑66421 Homburg/Saar, Germany
4. Department of Biophysics, Saarland University, D‑66421 Homburg/Saar, Germany