A Prospective Radiostereometric Analysis (RSA) and Clinical Evaluation of the Triathlon Tritanium Total Knee Replacement

Study Overview
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Brief Summary
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This study seeks to find out if the tibial and patellar components of the Stryker Triathlon Tritanium primary total knee replacement achieve adequate fixation to the underlying bone.

Detailed Description
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Primary Hypothesis: The investigators expect the tibial and patellar components of the Stryker Triathlon Tritanium knee to achieve adequate fixation to the underlying bone. Secondary Hypotheses: The investigators expect that there will be no continuous migration between one and two years post-operative in the Triathlon Tritanium components. The investigators expect to see a correlation between radiolucent lines and migration characteristics using RSA. The investigators expect that inducible displacement exams taken at 2 years post-operative will be able to distinguish between patients identified by RSA measurements as having inadequate fixation. The investigators expect to see a significant difference in health status and functional outcomes before and after total knee replacement using the Triathlon Tritanium knee.

Official Title
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A Prospective Radiostereometric Analysis (RSA) and Clinical Evaluation of the Triathlon Tritanium Total Knee Replacement

Conditions
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Osteoarthritis of the Knee

Intervention / Treatment
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* Device: Stryker Triathlon Tritanium primary knee


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Symptomatic osteoarthritis of the knee indicating surgical intervention Scheduled to undergo a total knee arthroplasty Patients between the ages of 18 and 80, inclusive Patient is a candidate for Triathlon Tritanium cementless knee components implanted in accordance with product labeling Exclusion Criteria: Significant co-morbidity affecting ability to ambulate Prior arthroplasty, patellectomy or osteotomy with the affected knee Active or prior infection of the affected knee Morbid obesity (BMI > 40) Medical condition precluding major surgery Severe osteoporosis Neuromuscular impairment Pregnancy Inability to give informed consent Inability to return for follow-up visits for a minimum of two years after surgery Currently participating in any other surgical intervention study Known allergy to metals Flexion contracture greater than 15° Extension lag greater than 10° Tibial subluxation greater than 10 mm on standing AP radiograph Lateral or medial collateral ligament instability (> 10° varus/valgus) Leg length discrepancy greater than 10 mm

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: Stryker Triathlon Tritanium primary knee|nan|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radiostereometric analysis of tibial and patellar components of the Stryker Triathlon Tritanium at 6 weeks, 3 months, 6 months, 1 year and 2 years. |  | 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Improved health status and functional outcomes as measured by the Knee Society Scoring System and EQ-5D questionnaires. |  | 3 years |