Vitamin E-enriched medium cross-linked polyethylene in total knee arthroplasty (VIKEP): clinical outcome, oxidation profile, and wear analysis in comparison to standard polyethylene-study protocol for a randomized controlled trial.

"Declarations Ethics approval and consent to participateThe study protocol and the written informed consent form (Additional file 2) were reviewed and positively rated by the corresponding ethics committee of each participating center (see Additional file 1). The primary positive vote was provided by the Ethikkommission an der Universitätsmedizin Rostock (A 2020–0171).Protocol amendments have to be endorsed by all investigators and respective ethics committees.All patients provided written informed consent prior to participation in the study. Consent for publicationNot applicable. Competing interestsAll authors filled and provided the ICMJE disclosure form. KM and MS are employees of Aesculap AG. AH declares that she has no conflict of interest. IK and MM declare that they received study grants from B.Braun/Aesculap AG for the conduction of this study and received support for attending/traveling to meetings from B.Braun/Aesculap AG. MH and OH declare that they received study grants from B.Braun/Aesculap AG for the conduction of this study and received honoraria for various lectures, workshops, and courses from B.Braun/Aesculap AG. JK declares that she received study grants from B.Braun/Aesculap AG for the conduction of this study and has an advisor contract for another study sponsored by B.Braun/Aesculap AG and received payments for a congress lecture and received support for attending/traveling to meetings from B.Braun/Aesculap AG. CL and WM declare that they received research grants from B.Braun/Aesculap AG and received support for attending/traveling to meetings from B.Braun/Aesculap AG. PM declares that he receives royalties/licenses from X.Nov and Adler. AN declares that he received study grants from B.Braun/Aesculap AG for the conduction of this study. BRD declares that he received study grants from B.Braun/Aesculap AG for the conduction of this study and received consulting fees from B.Braun/Aesculap AG and received support for attending/traveling to meetings from Leo Pharma. Competing interests All authors filled and provided the ICMJE disclosure form. KM and MS are employees of Aesculap AG. AH declares that she has no conflict of interest. IK and MM declare that they received study grants from B.Braun/Aesculap AG for the conduction of this study and received support for attending/traveling to meetings from B.Braun/Aesculap AG. MH and OH declare that they received study grants from B.Braun/Aesculap AG for the conduction of this study and received honoraria for various lectures, workshops, and courses from B.Braun/Aesculap AG. JK declares that she received study grants from B.Braun/Aesculap AG for the conduction of this study and has an advisor contract for another study sponsored by B.Braun/Aesculap AG and received payments for a congress lecture and received support for attending/traveling to meetings from B.Braun/Aesculap AG. CL and WM declare that they received research grants from B.Braun/Aesculap AG and received support for attending/traveling to meetings from B.Braun/Aesculap AG. PM declares that he receives royalties/licenses from X.Nov and Adler. AN declares that he received study grants from B.Braun/Aesculap AG for the conduction of this study. BRD declares that he received study grants from B.Braun/Aesculap AG for the conduction of this study and received consulting fees from B.Braun/Aesculap AG and received support for attending/traveling to meetings from Leo Pharma."

"Funding The study is funded by Aesculap AG (Tuttlingen, Germany), which is sponsor of the study. The study was initiated due to regulatory reasons but also to confirm biomechanical data of the new material in medium- and long-term application in vivo. Study planning was conducted in collaboration by the sponsor and the investigators. Principal investigators of all study centers agreed with the study protocol. The study report as well as manuscripts for publication in peer reviewed journals shall be agreed upon all study parties."

"Trial registration ClinicalTrials.gov, NCT04618016. Registered 27 October 2020, https://clinicaltrials.gov/study/NCT04618016?term=vikep&checkSpell=false&rank=1. All items from the World Health Organization Trial Registration Data Set can be found in Additional file 1."