DURATION STABILIZED UHMWPE KNEE COMPONENTS by HOWMEDICA CORP.

The Duracon®, P.C.A.® and Kinemax® Plus Tibial Inserts, All Plastic Tibial Components and Patellar Components (proviously cleared in K915512, K923573, K910235, K922048, K932070, K913188, K872735, K871772 and K921640) are intended to be used with Duracon®, P.C.A.® or Kinemax® femoral components, tibial baseplates and patellar components in primary or revision cemented total knee arthroplasty.

Device Description

This submission includes wear testing data on UHMWPE Knee Components sterilized by the method previously cleared in 510(k) submission K936292. This data is provided to substantiate claims of improved wear due to the processing of the devices. The submission includes Duracon®, P.C.A.® and Kinemax® Plus Tibial Inserts, All Plastic Tibial Components and Patellar Components which are intended to be used with Duracon®, P.C.A.® or Kinemax® Plus femoral components, tibial baseplates and patellar components in primary or revision cemented total knee arthroplasty.

AI/ML Overview

This submission details the wear testing of Howmedica's Duration™ Stabilized UHMWPE Knee Components to substantiate claims of improved wear. The study compares the wear performance of the stabilized UHMWPE against conventionally gamma sterilized UHMWPE in various in vitro wear tests.

Here is an analysis of the provided information:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Implicit)	Reported Device Performance
Demonstrate a reduction in volumetric wear of Duration™ Stabilized UHMWPE compared to conventionally gamma sterilized UHMWPE in a ring-on-block test.	A block of Duration™ Stabilized UHMWPE showed a 30% reduction in volumetric wear versus conventionally gamma sterilized UHMWPE. (Test duration: over 5 million cycles)
Demonstrate a reduction in volumetric wear of Duration™ Stabilized UHMWPE compared to conventionally gamma sterilized UHMWPE in a pin-on-disk test.	A 9mm thick circular disk of Duration™ Stabilized UHMWPE showed a 68% reduction in volumetric wear versus conventionally gamma sterilized UHMWPE. (Test duration: over 4 million cycles)
Demonstrate a reduction in volumetric wear of aged Duration™ Stabilized UHMWPE compared to aged conventionally gamma sterilized UHMWPE in a pin-on-disk test.	An aged (23 days heating in air, simulating 7-9 years of aging) 9mm thick circular disk of Duration™ Stabilized UHMWPE showed a 91% reduction in volumetric wear versus aged conventionally gamma sterilized UHMWPE. (Test duration: over 2.5 million cycles)

Note: The submission does not explicitly state pre-defined acceptance criteria in numerical terms (e.g., "must show at least X% reduction"). Instead, the reported device performance is the claim being substantiated, implying that any measured reduction in wear would be considered a positive outcome. The FDA's substantial equivalence determination suggests acceptance of these claims.

2. Sample Size Used for the Test Set and Data Provenance

Sample Size: The document refers to "a block" and "a 9mm thick circular disk" for the unaged tests, and "a 9 mm thick circular disk" for the aged test, both for the Duration™ Stabilized UHMWPE and the conventionally gamma sterilized UHMWPE for comparison. This phrasing suggests a sample size of one test article for each condition (stabilized vs. conventional, unaged vs. aged) for each type of test. However, wear testing typically involves multiple samples to ensure reproducibility and statistical significance. The limited detail provided here implies either a single sample per comparison or a simplified reporting of the outcome from multiple samples.
Data Provenance: The tests were conducted as "in vitro tests" in an "independent laboratory test." The country of origin is not specified but is presumably the USA, given the FDA 510(k) submission. The data is prospective in the sense that these were controlled experiments specifically designed to test the wear properties.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

Not applicable. This study involves in vitro mechanical wear testing, not a clinical study or diagnostic device assessment where expert opinion would establish ground truth. The "ground truth" for wear is established by the measured weight loss or volume displacement during the mechanical tests.

4. Adjudication Method for the Test Set

Not applicable. This is an in vitro mechanical test, not a clinical review requiring adjudication. The measurements of wear are objective.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done

No, an MRMC comparative effectiveness study was not done. This study is an in vitro mechanical wear test of materials, not a diagnostic imaging study involving human readers.

6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) was done

Yes, in a way. The tests performed are standalone in the sense that they are material property tests performed in a lab setting, independent of human interaction once initiated. There is no "algorithm" in the context of AI, but the measurements of wear are objective outcomes of the material's performance under simulated conditions.

7. The Type of Ground Truth Used

The ground truth used is measured volumetric wear. This is an objective measurement obtained through laboratory testing (reciprocating ring-on-block wear test and reciprocating pin-on-disk wear evaluations) using established scientific methods (weight loss to calculate volume change, or direct volume measurement if applicable).

8. The Sample Size for the Training Set

Not applicable. This study does not involve a "training set" in the context of machine learning or AI algorithms. It is an in vitro study of material properties.

9. How the Ground Truth for the Training Set Was Established

Not applicable, as there is no training set for an AI algorithm in this context.

Summary

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510(K) SUMMARY

June 11,
1997

Duration™ Stabilized UHMWPE Knee Components Trade Name:

UHMWPE Knee Components Common Name:

The following are the wear claims that will be made for these devices:

A block of Howmedica's Duration™ Stabilized UHMWPE showed a 30% reduction in volumetric wear versus the same block of Howmedica's conventionally gamma sterilized UHMWPE. Testing was performed in a reciprocating ring-on-block wear test for over 5 million cycles, using a circular disk, 2.83" in diameter, 1" wide, CoCr 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.

In an independent laboratory test, a 9mm thick circular disk of Howmedica's Duration™ Stabilized UHMWPE showed a 68% reduction in volumetric wear versus the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE. Testing was performed in a reciprocating pin-on-disk wear evaluation over 4 million cvcles, using a CoCr cylindrical pin with a 1" spherical end as the articulating counterface and boyine calf serum as a lubricant. The results of in vitro tests have not been shown to correlate with clinical wear mechanisms.

In an independent laboratory test, a 9 mm thick circular disk of Howmedica's Duration™ Stabilized UHMWPE, having undergone 23 days of heating in air to simulate 7-9 years of "aging", showed a 91% reduction in volumetric wear versus the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE, having undergone 23 days of heating in air to simulate 7-9 years of "aging". Testing was performed in a

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reciprocating pin-on-disk wear evaluations over 2.5 million cycles, using a CoCr cylindrical pin with a 1" spherical end as the 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: John Dichiara Manager, Regulatory Affairs Howmedica Inc. 359 Veterans Boulevard Ruthertord, NJ 07070 (201) 507-7386 - Phone (201) 507-6870 - Fax

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DURATION™ WEAR CLAIMS - KNEE COMPONENTS K965173

A block of Howmedica's Duration™ Stabilized UHMWPE showed a 30% reduction in volumetric wear versus the same block of Howmedica's conventionally gamma sterilized UHMWPE. Testing was performed in a reciprocating ring-on-block wear test for over 5 million cycles, using a clrcular disk, 2.83" in diameter, 1" wide, CoCr 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.

In an independent laboratory test, a 9 mm thick circular disk of Howmedica's Duration™ Stabilized UHMWPE showed a 68% reduction in volumetric wear versus the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE. Testing was performed in a reciprocating pin-on-disk wear evaluation over 4 million cycles, using a CoCr cylindrical pin with a 1" spherical end as the 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.

In an independent laboratory test, a 9 mm thick circular disk of Howmedica's Duration™ Stabilized UHMWPE, having undergone 23 days of healing in air to simulate 7-9 years of "aging", showed a 91% reduction in volumetric wear versus the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE, having undergone 23 days of heating in air to simulate 7-9 years of "aging". Testing was performed in a reciprocating pin-on-disk wear evaluations over 2.5 million cycles, using a CoCr cylindrical pin with a 1" spherical end as the 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.

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Image /page/3/Picture/1 description: The image shows the seal of the U.S. Department of Health and Human Services. The seal features a stylized eagle with its head turned to the right. The eagle's body is formed by three curved lines. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circle around the eagle.

JUN 11 1997

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Mr. John Dichiara Regulatory Affairs Manager Howmedica Inc. Division of Pfizer Hospital Products Group 359 Veterans Boulevard Rutherford, New Jersey 07070

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Re : K965173 Trade Name: Duration Stabilized UHMWPE - Knee Components Regulatory Class: II Product Codes: JWH and HRY Dated: March 21, 1997 Received: March 25, 1997

Dear Mr. Dichiara:

We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) 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 device, 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 device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Good Manufacturing Practice for Medical Devices: General (GMP) regulation (21 CFR Part 820) and that, through periodic

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Paqe 2 - Mr. John Dichiara

GMP inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP requlation may result in requlatory action. In addition, FDA may publish further announcements concerning your device 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 device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (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 device, 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 qeneral 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. Witten, Ph.D., M.D. Director Division of General and Restorative Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known): K965173

Device Name: Duration™ Stabilized UHMWPE Knee Components

Indications for Use:

SEE ADDITIONAL PAGE LABELED DURATION™ WEAR CLAIMS

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use (Per 21 CFR 801.109)

Over-The-Counter Use

ts cotle

(Optional Format 1-2-96)

965173

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.