Correction: European Spine Journal (2018) 27 (Suppl 4):S571–S573 https://doi.org/10.1007/s00586-018-5662-5

Unfortunately, the affiliation of the author group has been incorrectly published in original version. The complete correct affiliation of all authors should read as follows.


IRCCS Istituto Ortopedico Rizzoli, Via Giulio Cesare Pupilli 1, 40136, Bologna, Italy