title: Reply.
authors.affiliation: Department of Geriatrics, Neurosciences and Orthopaedics, Università Cattolica del Sacro Cuore, Largo Agostino Gemelli, Rome, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Cambise
authors.affiliation: Department of Geriatrics, Neurosciences and Orthopaedics, Università Cattolica del Sacro Cuore, Largo Agostino Gemelli, Rome, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Del Tedesco
authors.affiliation: Department of Geriatrics, Neurosciences and Orthopaedics, Università Cattolica del Sacro Cuore, Largo Agostino Gemelli, Rome, Italy.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Fernandez
authors.affiliation: Board of Physical Medicine and Rehabilitation, Department of Orthopaedic Science, "Sapienza" University, Rome, Italy.|Don Carlo Gnocchi Foundation, Milan, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Coraci
authors.affiliation: Board of Physical Medicine and Rehabilitation, Department of Orthopaedic Science, "Sapienza" University, Rome, Italy.|Physical Medicine and Rehabilitation Unit, Azienda Policlinico Umberto I, Rome, Italy.
authors.forename: Valter
authors.initials: V
authors.lastname: Santilli
authors.affiliation: Department of Geriatrics, Neurosciences and Orthopaedics, Università Cattolica del Sacro Cuore, Largo Agostino Gemelli, Rome, Italy.|Don Carlo Gnocchi Foundation, Milan, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Padua