|
General |
Study Status |
Completed |
Application Number / Requirement Number |
P010014 / PAS001 |
Date Original Protocol Accepted |
04/21/2004
|
Date Current Protocol Accepted |
01/04/2013
|
Study Name |
Long Term PAS
|
Device Name |
OXFORD(TM) MENISCAL UNICOMPARTMENTAL KNEE SYSTEM
|
General Study Protocol Parameters |
Study Design |
Prospective Cohort Study
|
Data Source |
New Data Collection
|
Comparison Group |
Historical Control
|
Analysis Type |
Analytical
|
Study Population |
Adult: >21
|
Detailed Study Protocol Parameters |
Study Objectives |
This is a prospective, multi-center, non-randomized study to evaluate two-year post-operative complications among patients implanted with Oxford Meniscal Unicompartmental Knee System and 9-year long-term survivorship of the device.
|
Study Population |
This device is indicated for use in patients with osteoarthritis or avascular necrosis limited to the medial compartment of the knee and intended to be implanted with bone cement. The study population includes patients who are 18 years or older, undergoing primary knee arthroplasty for either Osteoarthritis or Avascular necrosis of the medial compartment of the knee, and meet other inclusion/exclusion criteria will be included in this study.
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Sample Size |
389 knees
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Key Study Endpoints |
For Phase 1 (0-2 years), the study endpoint is complications, which is defined as "Any untoward medical occurrence in a patient administered a medical device and which does not necessarily have to have a causal relationship with this treatment. For Phase II, the study endpoint is "removal and/or revision of any component of the device".
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Follow-up Visits and Length of Follow-up |
In Phase 1, patients will be followed clinically at 6 weeks, 6 months, 1- year and 2- year post-operation. Information gathered includes all adverse events and survival data. In Phase II (3-9 year), only the device survival data will be gathered through patient direct mailing and/or phone call annually.
|
Interim or Final Data Summary |
Interim Results |
As of April 2, 2010, there have been 5 deaths reported due to pancreatic cancer (n=1), heart failure (n=1), leukemia (n=1), terminal illness (n=1) and unknown cause (n=1); as well as 11 revisions out of 388 knees implanted.
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Actual Number of Patients Enrolled |
The patient population includes 354 patients and 388 knees that underwent primary partial knee arthroplasty for either osteoarthritis or avascular necrosis of the medial compartment.
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Actual Number of Sites Enrolled |
A total of 6 clinical sites enrolled patients in the post-approval study.
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Patient Follow-up Rate |
The patient post-operative follow-up rates in the study were as follows: 98.2% at 6 weeks, 86.4% at 3 years, 84.2% at 6 years, 82.9% at 8 years and 82.4% at 9 years. The overall follow up rate is 86.8%.
|
Final Safety Findings |
There were 130 complications in 388 knees (16.8 complications/ 100 patient years) from the PAS group and there were 4 complications in 125 knees (1.6 complications /100 patient years) from the historical control IDE group (p-value <0.001). The overall 9-year revision rate is at least 12.4%.
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Final Effect Findings |
The 9-year cumulative device survivorship for all patients in this post-approval study was 86.56% (95% CI: 82.54, 89.71)
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Study Strengths & Weaknesses |
Study strengths included an adequate sample size and follow-up rate. A study weakness was the absence of optimal comparability for the collection of complication data between the post-approval study and historical control-IDE groups.
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Recommendations for Labeling Changes |
The labeling of this device should be updated with the results of this post-approval study.
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