1. Rheumatology Unit, University of Messina, Messina, Italy
2. Department of Rheumatology, ASST Fatebenefratelli-Sacco, Milan, Italy
3. Orthopedic Unit, Santissima Trinità Hospital, Cagliari, Italy
4. Department of Clinical Neurosciences, Villa San Benedetto Menni, Hermanas Hospitalarias, FoRiPsi, Como, Italy