Received: 29 November 2019
Accepted: 22 April 2020
First Online: 7 May 2020
Ethics approval and consent to participate
: the Ethics committee of Ospedale San Raffaele of Milan approved the present study. and all patients gave written consent to participate.
: Written informed consent to publish this information was obtained from study participants. All the data are available for the consultation.
: UGL is a member of the Editorial Board of BMC Musculoskeletal Disorders. The remaining authors declare that they have no conflict of interest.