1 Department of Orthopaedic and Traumatology, "Sapienza" University of Rome, Piazzale A. Moro, 3, 00185 Rome, Italy.
2 Department of Orthopaedic and Traumatology, "Sapienza" University of Rome, Piazzale A. Moro, 3, 00185 Rome, Italy. Electronic address: valeria.calogero@uniroma1.it.
3 Department of Pediatrics, "Sapienza" University of Rome, Viale Regina Elena, 324, 00161, Rome, Italy.