El-Bialy, Tarek
Alobeid, Ahmad
Dirk, Cornelius
Jäger, Andreas
Keilig, Ludger
Bourauel, Christoph
Article History
Received: 23 January 2018
Accepted: 17 December 2018
First Online: 13 February 2019
Compliance with ethical guidelines
:
: T. El-Bialy, A. Alobeid, C. Dirk, A. Jäger, L. Keilig and C. Bourauel declare that they have no competing interests.
: This article does not contain any studies with human participants or animals performed by any of the authors.