title: Commentary.
authors.affiliation: Department of Orthopedic Surgery, San Carlos University Hospital, Complutense University, C/Profesor Martín Lagos s/n, Madrid 28040, Spain.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Aparicio
authors.affiliation: Department of Preventive Medicine, Infanta Cristina Hospital, Parla, Madrid, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Bru