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Medacta GMK Sphere® Multicenter Post-Market Outcomes Study

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. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT02501733
Recruitment Status : Recruiting
First Posted : July 17, 2015
Last Update Posted : March 6, 2019
Information provided by (Responsible Party):
Medacta USA

Brief Summary:
This study is to average Forgotten Knee Score (FJS) of those patients receiving the Medacta GMK Sphere® knee at the two and five year time points. 70 subjects, enrolled at the data coordinating center in Medacta GMK Sphere® vs Posterior Stabilized study (WIRB Pro Num: 20141994) and randomized to the Sphere arm, will have their data utilized for this study.

Condition or disease Intervention/treatment Phase
Osteoarthritis Device: Medacta GMK Sphere® Medial Knee Prosthesis Not Applicable

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 200 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Medacta GMK Sphere® Medial Pivot, Cruciate Substituting Multicenter, Post-Market Outcomes Study
Study Start Date : June 2015
Estimated Primary Completion Date : July 2022
Estimated Study Completion Date : December 2023

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Artificial Limbs

Arm Intervention/treatment
Medacta GMK Sphere® Knee Prosthesis
All subjects enrolled will receive the Medacta GMK Sphere® Medial Knee Prosthesis
Device: Medacta GMK Sphere® Medial Knee Prosthesis

There is no consensus within the Arthroplasty community as to whether a traditional post and cam-style Posterior Stabilized total knee device is superior to a medial-pivot, more congruent device. However, the majority of surgeons seem to prefer the former, though there is a minority that uses the latter device with great success.

To date, there have been few prospective trials directly comparing these devices, and none with the latest generation of Total Knee Arthroplasty implants. Almost all such studies have been retrospective and/or utilizing older generation devices.

Other Names:
  • Total Knee Arthroplasty
  • Total Knee Prosthesis

Primary Outcome Measures :
  1. Evaluate the change in Forgotten Knee Scores (FJS) of those patients receiving the Medacta GMK Sphere from baseline to years 2 and 5 post-operatively. [ Time Frame: Baseline, 2 and 5 year time points ]
    Knee function-patients ability to forget the artificial joint in everyday life.

Secondary Outcome Measures :
  1. Total Knee Society Score (KSS) [ Time Frame: Pre-operative, 6 weeks, 3-6 months, 1,2,3,4 and 5 years. ]
    Total Knee Society score questionnaire to assess pain and function

  2. Krackow Activity Scale (KAS) [ Time Frame: Pre-operative, 6 weeks, 3-6 months, 1,2,3,4 and 5 years ]
    The Krackow Activity Scale (KAS) lower extremity activity scale.

  3. Radiographic Analysis [ Time Frame: Pre-operative, 6 weeks, 3-6 months, 1,2,3,4 and 5 years ]
  4. AP long standing X-ray [ Time Frame: Pre-operative and 6 weeks ]
    Determine degree of Varus or Valgus

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.

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Ages Eligible for Study:   21 Years to 80 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Patients willing to sign the informed consent
  • Patients able to comply with follow-up requirements including postoperative weight bearing restrictions and self evaluations.
  • Male and non-pregnant female patients ages 21 - 80 years of age at the time of surgery.
  • Patients requiring a primary total knee replacement.
  • Patients with a diagnosis of osteoarthritis (OA), traumatic arthritis (TA), or avascular necrosis (AVN).
  • Patients with intact collateral ligaments.

Exclusion Criteria:

  • Patients with inflammatory arthritis.
  • Patients that are morbidly obese, body mass index (BMI) > 40.
  • Patients with a history of total or unicompartmental reconstruction of the affected joint.
  • Patients that have had a high tibial osteotomy or femoral osteotomy.
  • Patients with neuromuscular or neurosensory deficiency, which would limit the ability to assess the performance of the device.
  • Patients with a systemic or metabolic disorder leading to progressive bone deterioration.
  • Patients that are immunologically compromised, or receiving chronic steroids (> 30 days).
  • Patients bone stock is compromised by disease or infection, which cannot provide adequate support and/or fixation to the prosthesis.
  • Patients with knee fusion to the affected joint.
  • Patients with an active or suspected latent infection in or about the knee joint.
  • Patients that are prisoners.

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): NCT02501733

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Contact: Mukesh Ahuja, MBBS, MS 312-548-9968

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United States, Illinois
Norhtwestern University Not yet recruiting
Chicago, Illinois, United States, 60611
Contact: David Manning, MD    312-695-1441   
Contact: Matthew Beal, MD    312-926-4444   
Principal Investigator: David Manning, MD         
Sub-Investigator: Matthew Beal, MD         
United States, Texas
Texas Institute for Hip and Knee Surgery Not yet recruiting
Austin, Texas, United States, 78751
Contact: David Dodgin, MD    512-476-2830   
Principal Investigator: David Dodgin, MD         
Texas Orthopedics Not yet recruiting
Austin, Texas, United States, 78759
Contact: Tyler Goldberg, MD    512-439-1001   
Principal Investigator: Tyler Goldberg, MD         
United States, Washington
Spokane Joint Replacement Center Recruiting
Spokane, Washington, United States, 99218
Contact: David Scott, MD    509-466-6393   
Principal Investigator: David F Scott, MD         
Sponsors and Collaborators
Medacta USA
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Study Director: Mukesh Ahuja, MBBS, MS Medacta USA, Inc.
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Responsible Party: Medacta USA Identifier: NCT02501733    
Other Study ID Numbers: 121416-01
First Posted: July 17, 2015    Key Record Dates
Last Update Posted: March 6, 2019
Last Verified: March 2019
Keywords provided by Medacta USA:
Total Knee Replacement
Total Knee Arthroplasty
Additional relevant MeSH terms:
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Joint Diseases
Musculoskeletal Diseases
Rheumatic Diseases