DURATION II TIBIAL INSERTS - GAS PLASMA STERILIZATION by HOWMEDICA CORP.

The intended use of this additional style of Duracon® Condylar and A-P lipped tibial inserts is identical to that of previously released Duracon® tibial inserts: they are intended to be used with Duracon® femoral and patellar components, and tibial baseplates in primary or revision cemented total knee arthroplasty.

Device Description

The purpose of this submission is to describe an additional style of Duracon® Condylar and A-P lipped tibial inserts which are stabilized/sterilized using a process called Duration® II Stabilization. The purpose of the Duration® II process is to crosslink all of the free radicals found in the UHMWPE rod stock by exposure to gamma radiation followed by a stabilization process in a heated oven. During this radiation/stabilization period, the UHMWPE is exposed to a very low oxygen concentration. The stabilized rod stock is then machined to its final configuration. The tibial insert is packaged in air, and terminally sterilized by the gas plasma sterilization process. The Duracon® Condylar and A-P lipped Inserts produced by this method conform to the requirements for Ultra High Molecular Weight Polyethylene specified in ASTM Specification F-648, and the FDA quidance document on UHMWPE used in Bearing Surfaces for Orthopedic Devices. As will be discussed later, this additional style of insert demonstrated significantly less wear when compared to air irradiated UHMWPE.

These Duracon® Condylar and A-P lipped inserts are identical to those previously released. They are available in peripheral sizes extra-small through extra-large in thicknesses from 6mm to 25mm. These inserts have a three point locking mechanism that is identical to those Duracon® inserts which have been previously released.

AI/ML Overview

The provided text describes the acceptance criteria and the study results for the Duration® II Duracon® Tibial Inserts - Gas Plasma Sterilization Device.

Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria / Claim	Reported Device Performance
1. Duration® II products meet all ASTM F 648 specified standards.	Duration® II Duracon® Tibial Inserts produced by this method conform to the requirements for Ultra High Molecular Weight Polyethylene specified in ASTM Specification F-648, and the FDA guidance document on UHMWPE used in Bearing Surfaces for Orthopedic Devices.
2. Duration® II products have no detectable oxidation as measured by FTIR up to 30 days of accelerated aging at 80° C in air.	Document states this is a marketing claim for the product. Specific FTIR data is not provided in the excerpt.
3. Duration® II products have a higher gel content (crosslinking) than air irradiated UHMWPE measured in accordance with modified ASTM D2765-90 standard.	Document states this is a marketing claim for the product. Specific gel content data for comparison is not provided in the excerpt.
4. Duration® II has a lower tensile modulus than air irradiated UHMWPE, leading to an increase in contact area and a decrease in contact stress.	Document states this is a marketing claim for the product. Specific tensile modulus, contact area, and contact stress data are not provided in the excerpt.
5. No free radicals are detected in the Duration® II material when analyzed by the ESR technique of the final product.	Document states this is a marketing claim for the product. Specific ESR technique results are not provided in the excerpt.
6. Duration® II has a lower wear rate, as measured by knee simulator testing, than air irradiated UHMWPE.	Howmedica's Duration® II Stabilized UHMWPE, Duracon® A-P lipped tibial insert (large, 19mm), exhibited an average total wear of 124.87 ± 15.0 mm³ versus 158.67 ± 11.0 mm³ average total wear for the same insert conventionally gamma sterilized in air.

2. Sample size used for the test set and the data provenance

Sample size for test set: The excerpt specifically mentions a "Duracon® A-P lipped tibial insert (large, 19mm)" being tested. While it provides an average wear rate with a standard deviation, it does not explicitly state the number of samples (n) used to calculate this average for both the Duration® II and the conventionally gamma sterilized inserts.
Data provenance: The data is described as "in vitro tests" using a "multiaxial knee joint simulator." This indicates the data is from prospective laboratory testing rather than human clinical data. The country of origin of the data is not specified, but the submission is to the FDA in the USA, implying the testing likely adheres to U.S. or international standards.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

This question is not applicable to this study. The "ground truth" for this device is not established by expert consensus on images or clinical outcomes, but by objective physical measurements (e.g., wear rate, material properties) conducted in a laboratory setting according to engineering standards (ASTM).

4. Adjudication method for the test set

This question is not applicable to this study. Adjudication methods (like 2+1, 3+1) are typically used in studies where human experts are making judgments, often in medical imaging or clinical trial outcome assessment. The reported study involves direct measurement of material properties and wear in a simulator.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

No, a MRMC comparative effectiveness study was not done. This type of study focuses on comparing human reader performance with and without AI assistance, which is irrelevant to the evaluation of a physical orthopedic implant.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

This question is not applicable to this study. This device is a physical implant, not an algorithm. The "standalone performance" here refers to the physical properties and wear characteristics of the material itself, which were tested in a simulator without human intervention in the 'reading' process.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The ground truth for this study is based on objective, quantitative physical measurements of material properties (e.g., conformance to ASTM F-648, gel content, tensile modulus, ESR for free radicals) and in vitro wear testing in a knee simulator.

8. The sample size for the training set

This question is not applicable to this study. This is a direct physical device evaluation, not a machine learning model, so there is no "training set."

9. How the ground truth for the training set was established

This question is not applicable for the same reason as above; there is no training set for a physical device evaluation.

Summary

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DEC 1 1 1998

K980633
510(k) Summary

Duration® II Duracon® Tibial Inserts - Gas Plasma Sterilization Device:

These inserts are substantially equivalent to the other Duracon® Condylar and A-P lipped tibial inserts which are already in distribution by Howmedica.

Testing was performed in accordance with the draft FDA guidance on UHMWPE.

The following marketing claims will be made for the product:

1. Duration® II products meet all ASTM F 648 specified standards
1. Duration® II products have no detectable oxidation as measured by FTIR up to 30 days of accelerated aging at 80° C in air.
റ്റ് Duration® II products have a higher gel content (crosslinking) than air irradiated UHMWPE measured in accordance with modified ASTM D2765-90 standard.

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1. Duration® II has a lower tensile modulus than air irradiated UHMWPE. This lower stiffness has demonstrated an increase in contact area and a decrease in contact stress.
No free radicals are detected in the Duration® II material when analyzed by ട. the ESR technique of the final product.
Duration® II has a lower wear rate, as measured by knee simulator testing, ୍. than air irradiated UHMWPE. Howmedica's Duration® II Stabilized UHMWPE, Duracon® A-P lipped tibial insert (large ,19mm), exhibited an average total wear of 124.87 ± 15.0 mm3 versus 158.67 ± 11.0 mm3 average total wear for the same insert conventionally gamma sterilized in air. Testing was performed in a multiaxial knee joint simulator for five million cycles using a Duracon® femoral component articulating counterface and bovine calf serum as a lubricant. The results of in vitro tests have not been shown to correlate with clinical wear mechanisms.

For information contact: Frank Maas Manager, Regulatory Affairs Howmedica Osteonics 359 Veterans Boulevard Rutherford, NJ 07070 (201) 507-7875

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Image /page/2/Picture/1 description: The image is a black and white logo for the U.S. Department of Health & Human Services. The logo features a stylized image of three human profiles facing right, with flowing lines connecting them. The profiles are arranged vertically, with the top profile slightly larger than the others. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular pattern around the image.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

DEC 1 1 1998

Mr. Frank Maas Manager, Regulatory Affairs Howmedica Inc. Pfizer Medical Technology Group 359 Veterans Boulevard 07070-2584 Rutherford, New Jersey

Re : K980626 Duration® II Acetabular Trade Name: Components - Gas Plasma Sterilization K980632 Duration II Tibial Trade Name: Inserts - Gas Plasma Sterilization Regulatory Class: II Product Code: JDI, LPH, and JWH September 18, 1998 Dated: September 18, 1998 Received:

Dear Mr. Maas:

We have reviewed your Section 510(k) notifications of intent to market the devices referenced above and we have determined these devices are substantially equivalent (for the indications for use stated in the enclosures) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the devices, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your devices are classified (see above) into either class II (Special Controls) or class III (Premarket Approval), they may be subject to such additional controls. Existing major regulations affecting your devices can be found in the Code of Federal Requlations, Title 21, Parts 800 to 895. ਉ substantially equivalent determination assumes compliance with the current Good Manufacturing Practice requirement, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic (QS) inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to

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Page 2 - Mr. Frank Maas

In addition, FDA may publish further announcements action. concerning your devices in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

This letter will allow you to begin marketing your devices as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your devices to legally marketed predicate devices results in a classification for your devices and thus, permits your devices to proceed to the market.

If you desire specific advice for your devices on our labeling requlation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4659. Additionally, for questions on the promotion and advertising of your devices, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to
premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its internet address "http://www.fda.qov/cdrh/dsmamain.html".

Sincerely yours,

Celia M. Whitton, Ph.D.

Celia M. Witten, Ph.D., M.D. Director Division of General and Restorative Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosures

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Indications for Use

510(k) Number (if known): K980632

Duration® II Duracon® Tibial Inserts - Gas Plasma Sterilization Device Name:

こし・んしたいい! いい

Indications for Use:

(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use
(Per 21 CFR 801.109)
OR
Over-The-Counter Use
No
(Optional Format 1-2-96)

(Division Sign-Off)
Division of General Restorative Devices K900632
510(k) Number

Regulation Number and Section

§ 888.3560 Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis.

(a)
Identification. A knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a knee joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components and a retropatellar resurfacing component made of ultra-high molecular weight polyethylene. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.