NitrX Total Knee Arthroplasty RSA

Study Overview
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Brief Summary
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Metal hypersensitivity is a recognized complication in some patients following total joint arthroplasty. This can result in a reaction to metal particles from the implants placed in the joint and cause tissue injury. The Evolution® NitrX™ (MicroPort Orthopaedics, Memphis, TN) knee implant was designed with the addition of a coating meant to create a barrier against the release of metal ions. The primary purpose of this study is to compare the Evolution and Evolution NitrX implant (implants your surgeon uses in total knee arthroplasty surgery). This study will compare the stability of these knee implants (any movement the implant makes after surgery) through the use of specialized xrays, called radiostereometric analysis (RSA for short). The investigators will also compare levels of circulating metal particles with blood draws and the effects of any circulating metal with MR imaging. The investigators will also be looking at the participants clinical outcomes using joint function and patient satisfaction questionnaires. A total of 50 patients will be enrolled into the study.

Official Title
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Component Migration, Polyethylene Wear, and Joint Inflammation of the Evolution Versus Evolution NitrX Total Knee Arthroplasty System

Conditions
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Total Knee Arthroplasty, Knee Osteoarthritis, Radiostereometric Analysis

Intervention / Treatment
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* Device: Total Knee Arthroplasty with Evolution® NitrX™ Knee System
* Device: Total Knee Arthroplasty with Evolution Knee System


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Symptomatic osteoarthritis of the knee indicating primary total knee arthroplasty Varus knee deformity of 0 to 10 degrees Sufficient ligamentous function to warrant retention of the posterior cruciate ligament Between ages of 21 and 80 inclusive Patients willing and able to comply with follow-up requirements and self-evaluations Ability to give informed consent No contraindications to Magnetic Resonance Imaging (MRI) Exclusion Criteria: Active or previous infection Medical condition precluding major surgery Inflammatory arthropathy Prior Patellectomy PCL deficiency Major Coronal plane deformity Valgus deformity Bone defects requiring augments, cones and/or stemmed implants

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 80 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Evolution Total Knee Arthroplasty system<br>Patients will undergo total knee arthroplasty with the Evolution Total Knee System | Device: Total Knee Arthroplasty with Evolution Knee System<br>* Patients will receive cemented Evolution knee system without NitrX coating for their total knee arthroplasty.<br>|
| Experimental: Evolution with NitrX Total Knee Arthroplasty system<br>Patients will undergo total knee arthroplasty with the NitrX Evolution Total Knee System which has the specialized protective coating | Device: Total Knee Arthroplasty with Evolution® NitrX™ Knee System<br>* Patients will receive cemented Evolution knee system with NitrX coating for their total knee arthroplasty.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Implant Migration (Tibial Component) | Model based Radiostereometric Analysis (RSA, specialized Xrays) will be used to register the location of the tibial implant components during supine and standing exams and measure implant movement. Changes throughout the different time points of potential tibial migration, with the use of the tibial bone beads, will be measured in millimeters. | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Implant Migration (Femoral Component) | Model based Radiostereometric Analysis (specialized Xrays) will be used to register the location of the femoral components during supine and standing exams and measure implant movement. Changes throughout the different time points of potential femoral migration, with the use of the femoral bone beads, will be measured in millimeters. | 2 years |