Triathlon® Cruciate Retaining (CR) Total Knee System Outcomes Study

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the clinical outcomes (range of motion, pain, function, radiographic stability, and health related quality of life) of patients receiving the Triathlon® Cruciate Retaining (CR) Total Knee System. These outcomes will be evaluated by comparing pre-operative to post-operative scores, as well as to a control group. The control group is the Scorpio® CR Total Knee System.

Detailed Description
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The Triathlon® Cruciate Retaining (CR) Total Knee System components are for use in cemented total knee arthroplasty for painful, disabling joint disease of the knee resulting from non-inflammatory degenerative joint disease (including osteoarthritis, traumatic arthritis or avascular necrosis) or rheumatoid arthritis (excluded from this study according to protocol). The components are designed to improve range of motion (ROM) and stability. This study serves to demonstrate that subjects have reduced pain, increased ROM and improved stability following implantation with the Triathlon Cruciate Retaining (CR) Total Knee System as compared to the historical control.

Official Title
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A Post-market, Non-randomized, Historical Controlled, Multi-center Study of the Outcomes of the Triathlon® Cruciate Retaining (CR) Total Knee System

Conditions
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Arthroplasty, Replacement, Knee

Intervention / Treatment
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* Device: Triathlon® CR Total Knee System


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The subject is a male or non-pregnant female between the ages of 21 and 80. The subject requires a primary cemented total knee replacement. The subject has a diagnosis of osteoarthritis (OA), traumatic arthritis (TA), or avascular necrosis (AVN). The subject has intact collateral ligaments. The subject has signed the IRB-approved, study specific Informed Patient Consent Form. The subject is willing and able to comply with postoperative scheduled clinical and radiographic evaluations and rehabilitation. Exclusion Criteria: Patient has inflammatory arthritis. The subject is morbidly obese, BMI > 40. The subject has a history of total or unicompartmental reconstruction of the affected joint. Patient has had a high tibial osteotomy or femoral osteotomy. The subject has no obvious charcot (i.e. a neuromuscular or neurosensory deficiency, which would limit the ability to assess the performance of the device). The patient has a systemic or metabolic disorder leading to progressive bone deterioration. The subject is immunologically suppressed, or receiving chronic steroids (> 30 days duration). The subject's bone stock is compromised by disease or infection, which cannot provide adequate support and/or fixation to the prothesis. The subject has had a knee fusion to the affected joint. The subject has an active or suspected latent infection in or about the knee joint. The subject is a prisoner.

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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Triathlon® CR Total Knee System<br>Participants receive the Triathlon® CR Total Knee System | Device: Triathlon® CR Total Knee System<br>* The purpose is to evaluate the Triathlon® CR Total Knee System.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Active Range of Motion |  | 2 Years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Knee Society Score (KSS) Over Time | The Knee Society Clinical Rating System is comprised of two distinct sub-scores: one for pain, ROM and joint stability, and one for functional parameters. Sub-scores range from a potential minimum score of 0 to a maximum score of 100 points. Although the specific scores are not distinguished as excellent, good, fair, or poor, a higher value represents a better outcome. | preoperative, 1, 2, and 5 years | 
| Active Flexion, Passive Flexion, Active Extension, and Passive Extension Range of Motion (ROM) | Knee range of motion is measured by the number of degrees flexion and extension observed. Active motion is the number of degrees that a participant can extend and flex their knee independently. Passive motion is the number of degrees that an examiner is able to extend and flex the knee without the assistance of the participant. The Knee Society Score range of motion utilized for this study defines the range from 0 degrees of extension to 125 degrees of flexion. | 1, 2, and 5 years | 
| Number of Knees With Radiographic Failure Assessed Via the Knee Society Total Knee Arthroplasty Roentgenographic Score | Parameters for radiographic failures will follow the guidelines that have been set by the Knee Society. The scoring system for each of the three components is determined by measuring the width of the radiolucent lines for each of the zones in millimeters for each of the three components. The total widths in millimeters are added for each zone for each of the three prostheses. The total produces a numerical score for each component. Failure is defined as a score of 10 or greater, regardless of symptoms. | 1, 2, and 5 years | 
| Change in SF-36 Health Survey Over Time | The SF-36 Health Survey is a 36 item patient completed questionnaire to measure general health and well-being. It includes a physical and mental status component score; each ranging from 0-100. Low values represent a poor health state and high values represent a good health state. | preoperative, 1, 2, 3, 4, and 5 years | 
| Change in Western Ontario and McMaster Osteoarthritis Index (WOMAC) Over Time | The WOMAC collects information specific to osteoarthritis outcomes. The questionnaire uses a visual analog scale for pain, measuring factors of general pain, stiffness, and physical findings. Pain is scored from 0 to 100 for each set of factors, with 0 indicating no pain and 100 indicating extreme pain. Total WOMAC scores range from 0 to 300. Lower values represent better outcomes. | preoperative,1, 2, 3, 4 and 5 years | 
| Change in Lower-Extremity Activity Scale (LEAS) Over Time | The LEAS is completed by the participant to assess activity level. Activity levels were ordered in terms of intensity from 1 to 18, with 18 indicating the highest activity level. | preoperative, 1, 2, 3, 4, and 5 years | 
| Patellar Subluxation, Dislocation and Fracture Rate | The incidence of patellar subluxation, dislocation or fracture is reported. | 5 years | 
| Patient Outcome Long Term Follow-up Questionnaire Over Time | Patient-reported outcome is collected using a long-term follow-up questionnaire at 6, 7, 8, 9, and 10 years postoperative for the subjects who consent to participation in the long-term follow-up study. The questionnaire consists of three yes or no questions: Do you have any pain in your knee that has the study knee replacement? Are you satisfied with the results of your study total knee replacement? Have you had any surgery on your study knee since the time of your last study required visit/contact? | 6, 7, 8, 9, and 10 years | 
| Implant Survivorship | Implant survivorship at 10 years postoperative is determined using the Kaplan-Meier method. | 10 years |