Kloth, Christopher
Thaiss, Wolfgang Maximilian
Beck, Robert
Haap, Michael
Fritz, Jan
Beer, Meinrad
Horger, Marius
Article History
Received: 18 February 2019
Accepted: 2 May 2019
First Online: 21 May 2019
Ethics approval and consent to participate
: For this retrospective study written informed consent was waived by the Institutional Review Board of the University of Tuebingen.
: Not applicable.
: The authors (CK, WMT, RB, MH, JF, MB, HM) declare that they have no competing interests.
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