X-3 Polyethylene Survival Outcomes Study

Arthroplasty, Replacement, Knee Clinical Trial

Official title:

A Prospective, Randomized Study Comparing the Survival for X-3 Polyethylene to N2Vac Polyethylene When Used With the Triathlon Posterior Stabilized (PS) Total Knee System.

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00493792
• Other study ID #: 06-003093
• Status: Completed
• Phase: N/A
• Start date: February 2007
• Est. completion date: November 1, 2023

Study information

• Verified date: June 2024
• Source: Mayo Clinic
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

A prospective, randomized, blinded clinical trial is proposed to compare Stryker Orthopaedics N2Vac Polyethylene to their X3 Polyethylene when used with the Triathlon Posterior Stabilized (PS) total knee system.

Description:

This is a fixed-bearing knee intended for use in patients undergoing cemented total knee arthroplasty. The devices to be used are both FDA approved via 510k clearance.

The study will aim for a total of 572 cases (286 per group). Each patient will be assessed pre-operatively and post-operatively at three months and two, five, seven and ten years. The primary endpoint will be the revision rate at ten years. The result for these will be analyzed using an unconditional test of equivalence between two independent binomials. Chi-square analysis will be used to compare the instance of mortality, revision surgery, deep vein thrombosis, pulmonary embolus, neurovascular complication, and infection. Other outcome measures incorporated in the Knee Society Clinical rating scale will undergo appropriate generalized linear regression for the type of outcome involved. The primary aim of the study is to compare the survivorship of two types of polyethylene (conventional N2Vac and highly cross-linked X3) used in a fixed-bearing total knee system in patients undergoing cemented total knee arthroplasty. These results will be measured through radiographs at each post-operative interval with an independent radiograph review being performed after all patients have reached 7 and 10 year follow-up. Secondary results will also be collected and will focus on disease-specific (Knee Society Scores), global (SF-12 v1), and outcome measures. Radiographic results consisting of standing anteroposterior, lateral and Merchant views of the surgical knee will be recorded and analyzed. Completion of the initial investigation will occur at the 10-year interval after the last enrolled.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 518
• Est. completion date: November 1, 2023
• Est. primary completion date: November 1, 2023
• Accepts healthy volunteers: No
• Gender: All
• Age group: 21 Years to 85 Years

Eligibility

INCLUSION CRITERIA:

1. Subjects willing to sign the informed consent.

2. Subjects able to comply with follow-up requirements including post-operative weight bearing restrictions and self-evaluations.

3. Male and non-pregnant female subjects ages 21-85 years of age at the time of surgery.

4. Subjects requiring a primary total knee replacement.

5. Subjects with a diagnosis of osteoarthritis (OA), traumatic arthritis (TA), or avascular necrosis (AVN).

6. Subjects with intact collateral ligaments as determined by the surgeon investigator.

EXCLUSION CRITERIA:

1. Subjects with inflammatory arthritis.

2. Subjects with a history of total or unicompartmental reconstruction of the affected joint.

3. Subjects that have had a high tibial osteotomy or femoral osteotomy.

4. Subjects with neuromuscular or neurosensory deficiency, which would limit the ability to assess the performance of the device.

5. Subjects with a systemic or metabolic disorder leading to progressive bone deterioration.

6. Subjects that are immunologically compromised, or receiving chronic steroids (>30 days).

7. Subjects bone stock is compromised by disease or infection that cannot provide adequate support and/or fixation to the prosthesis.

8. Subjects with knee fusion to the affected joint.

9. Subjects with an active or suspected latent infection in or about the knee joint.

10. Subjects that are prisoners.

Related Conditions & MeSH terms

• Arthroplasty, Replacement, Knee
• Total Knee Replacement

Intervention

Device:
• Stryker X3 Crosslink Polyethylene
Highly cross-linked polyethylene (HXLPE).
• N2Vac Polyethylene
Ultra-high-molecular-weight polyethylene (UHMWPE).

Locations

Country	Name	City	State
United States	Mayo Clinic	Jacksonville	Florida
United States	Mayo Clinic	Phoenix	Arizona
United States	Mayo Clinic	Rochester	Minnesota

Sponsors (2)

Lead Sponsor	Collaborator
Mayo Clinic	Stryker Orthopaedics

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Implant Survivorship Between N2Vac and Stryker X3: Free of Revision	Survivorship free of any revision at 10 years post-total knee arthroplasty.	10 years post-operative
Secondary	Implant Survivorship Between N2Vac and Stryker X3: Free of Reoperation	Survivorship free of any reoperation at 10 years post-total knee arthroplasty.	10 years post-operative
Secondary	Implant Survivorship Between N2Vac and Stryker X3: Free of Complications	Survivorship free of any non-revision and non-reoperation related complication at 10 years post-total knee arthroplasty.	10 years post-operative
Secondary	Knee Society Score (KSS)	The KSS evaluates pain, stability and range of motion. The maximum score of 100 points is reached when there is no pain, with good alignment of the knee in extension, and at least 125° of range of motion, without any anteroposterior or mediolateral instability. Deductions are made for flexion contracture, loss of extension and poor alignment.	Pre-operative, 3 months, 2, 5, 7 and 10-years post-operative
Secondary	Function Knee Society Score	The Function KSS evaluates the walking distance and the act of climbing and descending stairs. The maximum score of 100 points is attributed to the individual capable of walking unlimited distances without walking aids, and of climbing and descending stairs normally. Deductions are made for the use of canes, crutches or walking frame.	Pre-operative, 3 months, 2, 5, 7 and 10-years post-operative
Secondary	12-Item Short Form Health Survey (SF-12): Mental Health Score	The SF-12v2 questionnaire uses questions selected from the longer SF-36 Health Survey to measure patient wellness and quality of life. Responses were scored using the SF12v2 New England Medical Center (NEMC) scoring algorithm which converts the raw score from the questionnaire into a t-score. The algorithm is calibrated so that an average healthy person would have a t-score of 50 points with a standard deviation of 10. Higher scores indicate better mental health.	Pre-operative, 3 months, 2, 5, 7 and 10-years post-operative
Secondary	12-Item Short Form Health Survey (SF-12): Physical Health Score	The SF-12v2 questionnaire uses questions selected from the longer SF-36 Health Survey to measure patient wellness and quality of life. Responses were scored using the SF12v2 New England Medical Center (NEMC) scoring algorithm which converts the raw score from the questionnaire into a t-score. The algorithm is calibrated so that an average healthy person would have a t-score of 50 points with a standard deviation of 10. Higher scores indicate better physical health.	Pre-operative, 3 months, 2, 5, 7 and 10-years post-operative
Secondary	Comparison of Radiographic Success/Failure Between Groups	Radiographic evidence of loosening or osteolysis about the TKA prostheses.	10 years post-operative