The retrospective data analysis was conducted in accordance with the Helsinki Declaration of 1975, as revised in 2008, and all patients signed an informed consent. After consulting the local ethic committee, the decision was that due to the retrospective character of this study, with no additional data acquisition, no ethical approval is needed according to the hospital laws of the appropriate state (Landeskrankenhausgesetz Rhineland Palatinate, Germany).

All appropriate patients have signed a declaration of consent to publish their photos.

Stefan Wentaschek, Sinsa Hartmann, Christian Walter, and Wilfried Wagner declare that they have no competing interests.

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