COVID-19 is an emerging, rapidly evolving situation.
Get the latest public health information from CDC:

Get the latest research information from NIH: Menu

Stability of Contemporary Knee Arthroplasty

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02861794
Recruitment Status : Active, not recruiting
First Posted : August 10, 2016
Last Update Posted : January 10, 2019
Helse More and Romsdal Trust
Medacta International SA
Information provided by (Responsible Party):
Stephan M Rohrl, Oslo University Hospital

Brief Summary:
Total joint replacement is an efficacious treatment for osteoarthritis of hips and knees. Both total knee replacement (TKR) and total hip replacements (THR) have excellent implant survivorship. However, patients' satisfaction is lower in TKR than THR. A possible cause of the discrepancy is the unnatural knee kinematics after TKR. Various implants designs have been developed to solve the problem. However, most of their designs are based on experimental data and little has been studied about their actual performance in vivo. In this study, the investigators will analyze the in vivo stability of the Global Medacta Knee Sphere (GMK Sphere) implant. Migration of the implants will be monitored with a high precision measuring method called Radiostereometric Analysis (RSA). The investigators assume the investigators study will contribute the development of more satisfying knee implants.

Condition or disease Intervention/treatment Phase
Knee Osteoarthritis Procedure: GMK Sphere Not Applicable

Show Show detailed description

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 30 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Evaluation of Early Migration of Medially Stabilized Arthroplasty as a Predictor of Long Time Survivorship (Implant Design Study)
Study Start Date : May 2016
Estimated Primary Completion Date : May 2020
Estimated Study Completion Date : May 2020

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
GMK Sphere
Patients receive a GMK Sphere Total Knee Replacement.
Procedure: GMK Sphere
Total Knee Replacement

Primary Outcome Measures :
  1. Stability of the GMK Sphere prosthesis measured by Radiostereometric Analysis (RSA) [ Time Frame: 2 years ]
    Stability of the implant is measured in mm after 2 years (Maximum Total Point Motion in mm, MTPM)

Secondary Outcome Measures :
  1. Knee Society Score (KSS) [ Time Frame: 2 years ]
    Patient reported outcome measures

  2. Forgotten Joint Score 12 (FJS-12) [ Time Frame: 2 years ]
    Patient reported outcome measures

  3. Knee injury and Osteoarthritis Outcome Score (KOOS) [ Time Frame: 2 years ]
    Patient reported outcome measures

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   50 Years to 75 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Patients with knee osteoarthritis

Exclusion Criteria:

  • Preoperative severe deformity (Femoro-tibial angle < 175°or > 190°measured on a full-length leg image at weight bearing)
  • Preoperative flexion contracture more than 15°
  • Preoperative limited range of motion under anesthetics (less than 110°)
  • Less than 50 or 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 and avascular necrosis (e.g. rheumatoid arthritis, tumors)
  • Revision arthroplasty
  • Obesity with BMI >35
  • Impaired collateral ligaments
  • Malposition of femoral and tibial implants (Internally rotated or more than 10° externally rotated implants will be excluded. The rotation of femoral implant is measured on postoperative CT images in reference to surgical epicondylar line. The rotation of tibial implant is determined according to Berger's measurement)
  • Postoperative revision surgery due to deep wound infection

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT02861794

Layout table for location information
Oslo University Hospital
Oslo, Norway, 0470
Sponsors and Collaborators
Oslo University Hospital
Helse More and Romsdal Trust
Medacta International SA
Layout table for investigator information
Study Director: Stephan Maximillian Røhrl, MD, PhD Center for Implant and Radiostereometric Research Oslo (CIRRO)
Principal Investigator: Frank-David Oehrn, MD Kristiansund Hospital, Helse More and Romsdal Trust
Principal Investigator: Masako Tsukanaka, MD, PhD CIRRO

Layout table for additonal information
Responsible Party: Stephan M Rohrl, ass. professor, Oslo University Hospital Identifier: NCT02861794    
Other Study ID Numbers: 424444-1
First Posted: August 10, 2016    Key Record Dates
Last Update Posted: January 10, 2019
Last Verified: January 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Keywords provided by Stephan M Rohrl, Oslo University Hospital:
Total Knee Arthroplasty (TKA)
Total Knee Replacement (TKR)
Knee arthroplasty
Implant stability
Additional relevant MeSH terms:
Layout table for MeSH terms
Osteoarthritis, Knee
Joint Diseases
Musculoskeletal Diseases
Rheumatic Diseases