1. Department of Neurosurgery, Hospital Bretonneau, Tours
2. Department of Neurosurgery, Clairval Private Hospital, Ramsay Generale de Sante, Marseille
3. Department of Orthopaedic surgery, Trousseau Hospital, Tours
4. Department of Neurosurgery/Neurotraumatology, Hotel-Dieu Hospital, Nantes
5. Department of Orthopaedic Surgery, Pitié-Salpêtrière Hospital, Paris
6. Department of Neurosurgery, La Pitié-Salpêtrière Hospital, Paris, France