1. Department of Neurology IC, I.R.C.C.S. “Oasi” Institute for Research on Mental Retardation and Brain Aging, 73 Via Conte Ruggero, 94018 Troina, Italy
2. I.R.C.C.S. Centro Neurolesi “Bonino-Pulejo”, Via Provinciale Palermo, Contrada Casazza, 98124 Messina, Italy
3. Spinal Unit, Emergency Hospital “Cannizzaro”, 829 Via Messina, 95126 Catania, Italy
4. Department of Surgery and Medical-Surgical Specialties, University of Catania, 78 Via S. Sofia, 95123 Catania, Italy
5. Department of Medical and Surgical Sciences and Advanced Technology, Section of Neurosciences, University of Catania, 78 Via S. Sofia, 95123 Catania, Italy