Nicola Maffulli1, Giuseppe M Peretti2. 1. Department of Musculoskeletal Disorder, Faculty of Medicine and Surgery, University of Salerno, Salerno, Italy; Queen Mary University of London, Barts and the London School of Medicine and Dentistry, Centre for Sports and Exercise Medicine, Mile End Hospital, London E1 4DG, UK; School of Pharmacy and Bioengineering, Keele University School of Medicine, Stoke-on-Trent, UK. Electronic address: n.maffulli@qmul.ac.uk. 2. IRCCS Istituto Ortopedico Galeazzi, Milan, Italy; Department of Biomedical Sciences for Health, University of Milan, Milan, Italy.