Comparison of the in Vivo Stability of 2 Cementless TKA Designs (ClessTKA)

August 13, 2026 updated by: Helse Møre og Romsdal HF

Comparison of the in Vivo Stability of 2 Cementless TKA Designs Using CT Micromotion Analysis - A Randomized Controlled Trial

The goal of this randomized controlled trial is to analyze the stability of a cementless Total Knee Arthroplasty (TKA) over time and compare it to a well-documented implant in patients with knee osteoarthritis. The main aim is to answer if there is a difference in stability over time as a measure of long time survivorship in these 2 implants.

50 participants will be randomly allocated to receive either the Triathlon Tritanium (Stryker) or the Global Medacta Knee Sphere (GMK Sphere, Medacta) 3D printed cementless TKAs.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

Total joint replacement is an efficacious treatment for osteoarthritis of hips and knees. Both TKA and Total Hip Artrhoplasties (THA) have excellent implant survivorship. However, patients' satisfaction is lower in TKA than THA. A possible cause of the discrepancy is the unnatural knee kinematics after TKA. Various implants designs have been developed to solve the problem. The most common fixation mode is cemented TKA with good survival up to 15 years. However, newer series in younger patients also have shown lasting survival with cementless implants (Nilsson KG, Prudhon JL). Among various different designs, the medially stabilized total knee, which are designed to reproduce natural knee kinematics with a medial ball-in-socked design, is a promising implant design (No authors listed). Dynamically the medial pivot knee performs more naturally (Bragonzoni L,Petersen ET) compared to other designs. Most data for this design is available only for the cemented version. Up to now there is no safety study performed that confirms the stability over time for this implant with cementless fixation.

In this study, the investigators will therefore analyze the in vivo stability of an uncemented TKA with a medially stabilized design, and compare it with a well-documented comparable implant. In order to do this, the investigators will use the CT based micromotion analysis (Broden C, Broden C). This study will contribute to the understanding of fixation and lead to safety to the patient.

Study Type

Interventional

Enrollment (Actual)

50

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Norway
    • Møre and Romsdal
      • Kristiansund, Møre and Romsdal, Norway, 6508
        • Kristiansund Hospital, Møre and Romsdal Hospital Trust

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

46 years to 71 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

• Patients referred to Kristiansund Hospital for primary total knee replacement surgery for osteoarthritis with Kellgren & Lawrence grade 3 or 4

Exclusion Criteria:

  • Preoperative severe deformity (Hip-Knee-Ankle angle of >5 (valgus) or <-15 degrees (varus) on a full-length leg image at weight bearing
  • Preoperative flexion contracture more than 15°
  • Less than 50 and more than 75 years of age at the time of surgery
  • Use of walking aids because of other musculoskeletal and neuromuscular problems
  • Preoperative diagnosis other than osteoarthritis or avascular necrosis (e.g. rheumatoid arthritis, tumours)
  • Revision arthroplasty
  • Obesity with BMI>35 g/m2
  • Lateral collateral ligament deficient knee
  • Previous knee joint infection
  • Cognitive dysfunction or severe psychiatric disorders.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Control group
Cementless Triathlon Tritanium 3D printed TKA
Procedure: TKA
Total knee artroplasty with medial parapatellar incision and mechanical alignment without navigation
Experimental: Study group
GMK Sphere cementless 3D printed TKA
Procedure: TKA
Total knee artroplasty with medial parapatellar incision and mechanical alignment without navigation

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
CTMA Maximum Total Translation
Time Frame: Up to 2 years
The highest total translation on the implant at each time point
Up to 2 years
CTMA Maximum Total Translation
Time Frame: Up to 5 years
The highest total translation on the implant at each time point
Up to 5 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
CTMA Total rotation
Time Frame: Up to 2 years
Center of mass and peripheral points (degrees)
Up to 2 years
CTMA Total rotation
Time Frame: Up to 5 years
Center of mass and peripheral points (degrees)
Up to 5 years
CTMA Total translation
Time Frame: Up to 2 years
Center of mass and peripheral points (millimeters)
Up to 2 years
CTMA Total translation
Time Frame: Up to 5 years
Center of mass and peripheral points (millimeters)
Up to 5 years
The Forgotten Joint Score (FJS)
Time Frame: Up to 2 years
Patient Reported Outcome Measure PROMs). 12 item likert scale with scores from 0-4 (0=never, 4= allways). Mean value is multiplied with 25 and the subtracted from 100. Maximum score i 100 (excellent), minimum score is 0 (worse).
Up to 2 years
The Forgotten Joint Score (FJS)
Time Frame: Up to 5 years
Patient Reported Outcome Measure PROMs). 12 item likert scale with scores from 0-4 (0=never, 4= allways). Mean value is multiplied with 25 and the subtracted from 100. Maximum score i 100 (excellent), minimum score is 0 (worse).
Up to 5 years
The Knee injury and Osteoarthritis Outcome Score (KOOS)
Time Frame: Up to 2 years
Patient Reported Outcome Measure (PROMs). KOOS consists of 5 subscales; Pain, other Symptoms, Activites of Daily Living (ADL), Sport and Recreation Function (Sport/Rec) and knee-related Quality of Life (QOL). The previous week is the time period considered when answering the questions. Standardized answer options are given (5 Likert boxes) and each question is assigned a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale
Up to 2 years
The Knee injury and Osteoarthritis Outcome Score (KOOS)
Time Frame: Up to 5 years
Patient Reported Outcome Measure (PROMs). KOOS consists of 5 subscales; Pain, other Symptoms, Activites of Daily Living (ADL), Sport and Recreation Function (Sport/Rec) and knee-related Quality of Life (QOL). The previous week is the time period considered when answering the questions. Standardized answer options are given (5 Likert boxes) and each question is assigned a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale
Up to 5 years
Range of motion
Time Frame: Up to 2 years
From full extension to full flexion (degrees)
Up to 2 years
Range of motion
Time Frame: Up to 5 years
From full extension to full flexion (degrees)
Up to 5 years
HKA
Time Frame: Up to 2 years
Hip knee ankle angle measured on X-ray (degrees). Deviation from 0 is either varus (-) or valgus (+)
Up to 2 years
HKA
Time Frame: Up to 5 years
Hip knee ankle angle measured on X-ray (degrees). Deviation from 0 is either varus (-) or valgus (+)
Up to 5 years

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
BMI
Time Frame: Preoperative
Body mass index (kg/m2)
Preoperative
Operation time
Time Frame: Intraoperative
Time used in minutes from skin incision to wound closure.
Intraoperative
Axial alignment of the tibia
Time Frame: Up to 1 week postoperative
Measured by Bergers method (degrees internal or extarnal rotation)
Up to 1 week postoperative

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Helse Møre og Romsdal HF

Collaborators

Oslo University Hospital
Medacta International SA

Investigators

  • Study Director: Frank-David Øhrn, MD, PhD, Møre og Romsdal Hospital Trust
  • Study Chair: Stephan M Röhrl, MD, PhD, Oslo University Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 6, 2022

Primary Completion (Estimated)

June 25, 2028

Study Completion (Estimated)

January 1, 2033

Study Registration Dates

First Submitted

November 23, 2022

First Submitted That Met QC Criteria

December 6, 2022

First Posted (Actual)

December 14, 2022

Study Record Updates

Last Update Posted (Actual)

August 17, 2026

Last Update Submitted That Met QC Criteria

August 13, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 520246

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Individual participant data that underlie the results reported in this article, after deidentification

IPD Sharing Time Frame

Immediately following publication and 5 years

IPD Sharing Access Criteria

Researchers that want access to data

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP
  • CSR

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Subscribe