1. Ludwig Boltzmann Institute for Experimental and Clinical Traumatology and Research Unit of the Austrian Workers' Compensation Board (AUVA), Vienna, Austria.
2. Trauma Hospital Linz of the AUVA, Linz, Austria.
3. Department of Traumatology, Waldviertel Clinic, Horn, Austria.
4. Department of Neurosurgery, Neurocenter, Johann Wolfgang Goethe University, Frankfurt am Main, Germany.