1. Department of Neurosurgery, IRCCS Ospedale Policlinico San Martino, Genova, Italy
2. Università di Genova, Genova, Italy
3. Department of Neurosurgery, Università Degli Studi dI Torino, Torino, Italy
4. Department of Peripheral Nerve Surgery, Ospedale Civile Degli Infermi, Faenza, Italy