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Active, not recruitingNCT04618016VIKEPUpdated Oct 20, 2026

Evaluation of Medium Cross-linked Polyethylene With and Without Vitamin E for Total Knee Arthroplasty

An observational study in Osteoarthritis, Knee, Arthritis, Rheumatoid and Intra-Articular Fractures, sponsored by Aesculap AG. Active, not recruiting at 8 sites in 2 countries. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-10-20.

Sponsored by Aesculap AG (part of B. Braun) · Observational

Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
605
Ages
18 Years to 80 Years
Sex
All
01

Study summary

Prospective, randomized, single-blind, multinational, long-term study for the evaluation of the clinical outcome, oxidation profile and wear analysis of medium cross-linked Polyethylene with and without Vitamin E for total knee arthroplasty

02

Conditions studied

  • Osteoarthritis, Knee
  • Arthritis, Rheumatoid
  • Intra-Articular Fractures
  • Joint Instability
  • Genu Valgum or Varum

Keywords

  • Total Knee Arthroplasty
  • Range of motion
  • Treatment outcome
  • Ultrahighmolecular Weight Polyethylene with Vitamin E
03

In context

Osteoarthritis, Knee

3,292 studies on the registry are indexed under Osteoarthritis, Knee; 623 are open to participants now.

This study's enrollment of 605 is above the median of 100 across 486 observational studies indexed under Osteoarthritis, Knee.

Browse Osteoarthritis, Knee studies →

Lead sponsor

Aesculap AG is the lead sponsor of 105 studies on the registry; 20 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 80 Years
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Probability sample

Study population

multicentric

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Indication for a total knee replacement with a mobile-bearing UC or PS inlay
  • Written for participating at the clinical study
  • Willingness and mental ability to participate at the long-term follow-up examinations

Exclusion criteria

Exclusion Criteria:

  • Patient age \< 18 and > 80 years
  • Pregnancy
  • High risk patients ( >3)
Terms in these criteria, in plain language(2)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

ASA physical status

The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.

05

Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
605 participants (actual)

Groups and cohorts

  • With Vitamin E

    Device: UHMWPE with Vitamin E

  • Without Vitamin E

    Device: UHMWPE without Vitamin E

Interventions

  • DeviceUHMWPE with Vitamin E

    e.motion Pro (PS and UC) with MXE gliding surface

  • DeviceUHMWPE without Vitamin E

    e.motion Pro (PS and UC) with β-PE gliding surface

06

What researchers measure

Primary outcomes

  1. Clinical Outcome measured with the KSS [performance]

    The KSS is an examiner-administrated standard clinical evaluation tool reporting results for patients undergoing TKA. It separates findings in the operated knee (kKSS) score from findings related to the patient's function (fKSS), which might be affected by co-morbidities. The two sub-scores are reported separately ranging from 0 points (worst result) to 100 points (best results), as well as summarized score, total KSS. Final grading of total KSS results Scores of 160 to 200 will be rated as excellent, 140 to 159 as good, 120 to 139 as fair, and less than 120 as poor.

    Time frame: 10 years postoperatively

Secondary outcomes

  1. Survival rate

    Kaplan-Meier Analysis is a standard statistical method to describe the survival of human subjects or medical products over a defined time period. The revision-free survival rate is the performance indicator of the product under investigation and confirms the clinical outcome of the knee prosthesis. Information on survival of the implant will be collected until the last follow-up of the study patients took place.

    Time frame: until the last follow-up at 10 years postoperatively

  2. Progress of Clinical Outcome [Oxford Knee Score] compared to baseline

    The Oxford Knee Score is a reliable 12-item, patient-reported questionnaire originally developed and validated specifically to assess function and pain in patients undergoing total knee replacement. It is short, reproducible, valid and sensitive to clinically important changes over time. Each of the 12 questions on the OKS is scored in the same way with the score decreasing as the reported symptoms increase (i.e. become worse). All questions are laid out with response categories denoting least (or no) symptoms to the left of the page (scoring 4) and those representing greatest severity lying on the right hand side (scoring 0), as detailed for question 1 below. This method, when summed, produces overall scores running from 0 to 48 with 48 being the best outcome, (to convert from the 60-12 system to the 0-48 system and vice versa subtract the score from 60).

    Time frame: Preoperatively, 3 months, 12 months, 3 years, 5 years, 7 years, 10 years

  3. Quality of Life [EQ-5D-5L]

    EQ-5D is a standardized 5-dimension 5-level measure of the health status and is developed by the EuroQol Group in order to have a simple and generic measure for clinical and economic assessment. Instructions for the user are directly included into the questionnaire and it consists of two pages. One cover five different dimensions (mobility, self care, usual activities, pain/discomfort, anxiety/depression) and the other one the EQ visual Analogue Scale (EQ-VAS). The VAS scale records the self rated health status of the patient from the level "the worst health you can imagine" to "the best health you can imagine".

    Time frame: Preoperatively, 3 months, 12 months, 5 years, 10 years

  4. Comparison of Radiographic evaluation over time

    Imaging will be used to evaluate the implant status as well as device condition and potential presence of device-related Adverse Events including fracture, wear, loosening or radiolucencies.

    Time frame: baseline (assessed at discharge from hospital up to 10 days postoperatively); 3 months; 12 months; 5 years; 10 years

  5. Comparison of Radiographic alignment over time

    Alignment (femoral-knee baseline angle, tibial-knee baseline angle, femoral-tibial angle (mechanical))

    Time frame: baseline (assessed at discharge from hospital up to 10 days postoperatively); 3 months; 12 months; 5 years; 10 years

  6. Oxidation profile and wear analysis of available retrievals

    Available retrievals of explanted investigational products will be analysed by the biomechanical laboratory of the sponsor. Therefore any retrieval has to be returned to the Sponsor's facility after its revision in order to perform these analyses. Special focus of theses analyses are the oxidation profile, the wear behaviour, the mechanics and the cumulative linear abrasion of these retrievals. These measurements can further analyse the in-vivo performance of the device of the reference and investigational product

    Time frame: During the course of the study up to 10 years postoperatively

  7. Further analysis of patients having a revision of the primary implant

    In case a patient requires the revision of the primary implanted knee prosthesis, additional information on the revision surgery shall be collected. The reason for revision together with the clinical symptoms shall be documented. Further examinations (e.g. arthroscopy) prior to the revision and the date of revision surgery is to be documented. If pre revision radiographs are taken as part of the clinical routine, the results of the radiographic analysis shall be documented in the respective CRF.

    Time frame: During the course of the study up to 10 years postoperatively

  8. (Serious) Adverse Events

    During the course of the study, any upcoming intra- or postoperative (serious) adverse device events or effects related or not related to the product under investigation, will be documented. The total number of AEs will be summarized and further evaluated by the sponsor and reported according to local legislation and necessity. Recorded complications will be categorized and analyzed in order to assess the safety of the investigational product.

    Time frame: During the course of the study up to 10 years postoperatively

07

Study locations

8 sites
08

References and documents

Publications

  • Maier K, Selig M, Haddouche A, Haunschild M, Hauschild O, Khalili I, Kirschberg J, Lutter C, Menges M, Mertl P, Niemeier A, Rubens-Duval B, Mittelmeier W. 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. Trials. 2024 Jan 5;25(1):27. doi: 10.1186/s13063-023-07811-1. PubMed 38183062 ↗
09

Timeline

1 registry update since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Mar 2021 to primary completion in Dec 2024, 45 months.

Of 220 observational studies under Osteoarthritis, Knee, half reached primary completion within 24 months of starting (the median), counting those still running; a quarter within 14 and three quarters within 61. This study's 45 months is above that.

How these figures are worked out, and which studies are left out of them.

Registered
Oct 27, 2020
First posted
Nov 5, 2020
StartActual
Mar 8, 2021
Primary completionActual
Dec 31, 2024
CompletionEst.
Oct 2034
Last update
Oct 20, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
Secondary outcomes
1 edited
What changed in the outcomes
  • EditedProgress of Clinical Outcome [Oxford Knee Score] compared to baselineTime frame: Preoperatively, 3 months, 12 months, 3 years, 5 years, 7 years, 10 years
Oct 20, 2026
Show all 1 update
  1. Oct 20, 2026
    Secondary outcomes 1 edited
    What changed in the outcomes
    • EditedProgress of Clinical Outcome [Oxford Knee Score] compared to baselineTime frame: Preoperatively, 3 months, 12 months, 3 years, 5 years, 7 years, 10 years
    + 1 other change: verification date

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT04618016
Lead sponsor
Aesculap AG
Collaborators
Raylytic GmbH, B. Braun Medical France
Responsible party
Sponsor
First posted
Nov 5, 2020
Start date
Mar 8, 2021
Primary completion
Dec 31, 2024
Completion
Oct 2034 (estimated)
Last update
Oct 20, 2026

Study contacts

Wolfram Mittelmeier, Prof. Dr.
principal investigator · Orthopädische Uniklinik Rostock, Direktor
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is active, not recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.

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