Funding for this research was provided by:
Inneruniversitäre Forschungsförderung Stufe I
German Society of Shoulder and Elbow Surgery
Received: 26 October 2017
Accepted: 17 July 2018
First Online: 25 July 2018
: This study was approved by the local ethics committee “Landesuntersuchungsamt Rheinland-Pfalz” (ID 23 177-07/G 13-1-043 E1).
: Not applicable.
: The authors declare that they have no competing interests.
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