3DKnee™ System vs. the MJS Knee System

Study Overview
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Brief Summary
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The purpose of this study is to compare the survivorship and efficacy of the Encore 3DKnee™ system with that of the Encore MJS™ Knee System in a group of 600 patients for whom data collection is already under way.

Detailed Description
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The purpose of this study is to compare the survivorship and efficacy of the Encore 3DKnee™ system with that of the Encore MJS™ Knee System in a group of 600 patients for whom data collection is already under way. Approximately 300 patients have already received the MJS™ knee system and data, as described below, has been collected for these patients over a period of two years. A second group of 300 patients will receive the Encore 3DKnee™ system over the next two years, and equivalent data will be collected for these individuals. A portion of the data has been collected over the past year, and now we would like to obtain permission from the patients to analyze these data as well as collect an additional year of data.

Official Title
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Post-Market Study: The Efficacy of the 3DKnee™ System vs. the MJS Knee System

Conditions
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Rheumatoid Arthritis, Traumatic Arthritis, Joint Disease Secondary to Osteoarthritis

Intervention / Treatment
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* Device: Encore 3DKnee™ system
* Device: Encore MJS™ Knee System


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: This must be a primary knee replacement on this knee. Patient is over 18 years of age or older Patients must have one of the following rheumatoid or traumatic arthritis OR joint disease secondary to osteoarthritis Patient is likely to be available for evaluation for the duration of the study Able and willing to sign the informed consent and follow study procedures Patient is not pregnant Exclusion Criteria: Is younger than 18 years of age If there has been a total knee replacement on this knee in the past (no revisions allowed in study) Overt infection Alcoholism or other addictions Muscular, neurological or vascular deficiencies which compromise the affected extremity Obesity Marked bone loss Materials sensitivity Prisoner Mental conditions that may interfere with the patient's ability to give an informed consent or willingness to fulfill the study requirements Patient is pregnant

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 2<br>Subjects who meet the indications for use and are implanted with the Encore MJS™ Knee System. | Device: Encore MJS™ Knee System<br>* Subjects with rheumatoid arthritis, traumatic arthritis or osteoarthritis who were implanted with the Encore MJS™ Knee system and willing to participate in the study.<br>|
| 1<br>Subjects who meet the indications for and are implanted with the Encore 3DKnee™ system. | Device: Encore 3DKnee™ system<br>* Subjects with rheumatoid arthritis, traumatic arthritis or osteoarthritis who were implanted with the Encore 3DKnee™ system and willing to participate in the study.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The survivorship and efficacy of the Encore 3DKnee™ system with that of the Encore MJS™ Knee System |  | 2 year |