Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (Be 804/18-1)
Bundesministerium für Bildung und Forschung (01EC1408A)
Received: 26 April 2018
Accepted: 12 October 2018
First Online: 8 November 2018
Ethics approval and consent to participate
: All subjects gave written informed consent to participate in the investigations. The study was approved by the ethics committee of the Charité – Universitätsmedizin Berlin (reference number: EA4/069/06), and registered at the German Clinical Trials Register (reference number: DRKS00000606).
: All patients gave written informed consent to having their images published.
: T. Pfitzner reports speaker fees from Link, Smith & Nephew and consultancy fees from DepuySynthes.
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