The PCA® Primary Inserts for Duracon® Baseplates (K936008), PCA® Modular Inserts for Duracon® Baseplates (K940861), PCA® Modular Primary/Revision Patella (K940713), Duracon® Recessed Patella (K951655), Duracon® Inset Patella with Central Peg (K961482), Duracon® All Poly Patella II (K961483), Duracon® Extra Small Tibial Stabilizer Insert (K970758), Kinematic® All Poly Patella with Three Pegs (K971550), and the Kinematic® II Replacement Tibial Inserts (K960976) are intended was a to be used with the PCA®, Duracon®, or Kinemax® family of femoral components, tibial baseplates, and patellar components in primary or revision cemented total knee arthroplasty.

Device Description

This submission describes additional UHMWPE Knee components that have been previously cleared for sterilization by the Duration® Stabilized process and are to be added to the list of devices cleared for the corresponding wear claims in submission K965173. The additional products are described below, as are the wear claims from K965173.

The products that have been added to the list of devices cleared for the wear claims are: The PCA® Primary Inserts for Duracon® Baseplates (K936008), PCA® Modular Inserts for Duracon® Baseplates (K940861), PCA® Modular Primary/Revision Patella (K940713), Duracon® Recessed Patella (K951655), Duracon® Inset Patella with Central Peg (K961482), Duracon® All Poly Patella II (K961483), Duracon® Extra Small Tibial Stabilizer Insert (K970758), Kinematic® All Poly Patella with Three Pegs (K971550), and the Kinematic® II Replacement Tibial Inserts (K960976). These components are intended to be used with the PCA®, Duracon®, or Kinemax® family of femoral components, tibial baseplates, and patellar components in primary or revision cemented total knee arthroplasty.

AI/ML Overview

The provided text describes wear claims for Howmedica's Duration® Stabilized UHMWPE Knee Components based on in vitro laboratory tests. The document repeatedly states that "The results of in vitro tests have not been shown to correlate with clinical wear mechanisms," which is a crucial disclaimer when interpreting the data.

Here's a breakdown of the requested information based on the provided text, with clarifications where the information is not directly available:

1. Table of Acceptance Criteria and Reported Device Performance

The submission does not explicitly state "acceptance criteria" in the traditional sense of a predetermined threshold that the device must meet to be considered effective. Instead, it presents wear claims as observed reductions in volumetric wear compared to a conventional material. The "acceptance criteria" are implied by the reported reductions themselves, showcasing the improved performance of the stabilized UHMWPE.

Test Scenario	Implicit "Acceptance Criteria" (Demonstrated Improvement)	Reported Device Performance (Reduction in Volumetric Wear)
Reciprocating ring-on-block wear test (over 5 million cycles) - Stabilized vs. conventionally gamma sterilized UHMWPE block	Significant reduction in wear	30% reduction
Independent laboratory reciprocating pin-on-disk wear evaluation (over 4 million cycles) - Stabilized vs. conventionally gamma sterilized UHMWPE circular disk	Significant reduction in wear	68% reduction
Independent laboratory reciprocating pin-on-disk wear evaluation (over 2.5 million cycles) - Aged Stabilized (simulating 7-9 years of aging) vs. aged conventionally gamma sterilized UHMWPE circular disk	Significant reduction in wear	91% reduction

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

The document describes the test samples rather than a "test set" in the context of a statistical study with a specific sample size (N). The tests involved specific physical samples:

Reciprocating ring-on-block test: "A block of Howmedica's Duration® Stabilized UHMWPE" and "the same block of Howmedica's conventionally gamma sterilized UHMWPE." This implies a comparison between two samples (one stabilized, one conventional).
Independent pin-on-disk tests: "a 9mm thick circular disk of Howmedica's Duration® Stabilized UHMWPE" and "the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE" (for both the unaged and aged comparisons). This also implies a comparison between two samples for each test.

Sample Sizes: For each test described, the comparison appears to be one-to-one, comparing a stabilized sample directly against a conventional sample. The total number of individual samples tested across all three scenarios would be small (e.g., 2 blocks, 4 disks).

Data Provenance: The data is generated from in vitro laboratory tests.

The first test (ring-on-block) is described as being performed internally ("Howmedica's Duration® Stabilized UHMWPE").
The second and third tests (pin-on-disk) are explicitly stated as being performed in "an independent laboratory test."

The country of origin is not specified, but Howmedica Inc. is based in Rutherford, New Jersey, USA. The data is retrospective in the sense that the tests were conducted prior to this 510(k) submission, but it's not "retrospective clinical data."

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

N/A. This is a technical performance study of materials (wear testing) and does not involve human interpretation or subjective assessment of physiological conditions. Therefore, there is no "ground truth" established by experts in the medical diagnostic sense. The ground truth for volumetric wear is established by the physical measurement methods used in the laboratory tests.

4. Adjudication Method for the Test Set

N/A. As this is a physical wear testing study, there is no team of human adjudicators reviewing output. The "adjudication" is inherent in the standardized measurement protocols of the wear tests.

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

No. This document describes in vitro wear testing of materials, not a clinical study involving human readers or cases. Therefore, an MRMC comparative effectiveness study was not performed, and there is no effect size related to human reader improvement with AI.

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

N/A. This is not an AI/algorithm-based device. It is a physical medical device (UHMWPE knee components) whose performance is evaluated through mechanical in vitro tests.

7. The Type of Ground Truth Used

The ground truth used is physical measurement of volumetric wear. This is determined by the methodologies of the reciprocating ring-on-block and pin-on-disk wear tests, which are standardized engineering and materials science techniques.

8. The Sample Size for the Training Set

N/A. This is not an AI/machine learning device; therefore, there is no concept of a "training set" in the context of an algorithm. The UHMWPE material itself is a product of manufacturing processes, and its inherent properties (including resistance to wear) are determined by its formulation and stabilization process.

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

N/A. As there is no training set for an algorithm, there is no ground truth established for it.

Summary

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K972864

510(k) Summary

Proprietary Name: Duration® Stabilized UHMWPE Knee Components, Wear Claims

Common Name: UHMWPE Knee Components

OCT 2 9 1997

21 CFR 888.3560 Classification Name and Reference:

Proposed Regulatory Class: Class II Device Product Code: JWH

For information contact: Frank Maas Manager, Regulatory Affairs Howmedica Inc. 359 Veterans Boulevard Rutherford, NJ 07070 Telephone: (201) 507-7875 (201) 507-6870 Fax: Date Summary Prepared: 8-1-97

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

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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 cycles, using a CoCr cvlindrical 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 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 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/2/Picture/1 description: The image shows the logo for the U.S. Department of Health and Human Services. The logo consists of a circle with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" around the perimeter. Inside the circle is an abstract symbol that resembles a stylized eagle or bird with three human profiles incorporated into its design.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

OCT 2 9 1997

Mr. Frank Maas Requlatory Affairs Manager Howmedica, Inc. Pfizer Hospital Products Group 359 Veterans Boulevard Rutherford, New Jersey 07070-2584

Re: K972864 Trade Name: Duration® Stabilized UHMWPE Knee Components Regulatory Class: II Product Code: JWH Dated: August 1, 1997 Received: August 4, 1997

Dear Mr. Maas:

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). This decision is based on this device being equivalent only to similar devices labeled and intended to be fixed within bone with acrylic "bone cement." You may, therefore, market your device subject to · the general controls provisions of the Act and the followinq limitations:

1 . This device may not be labeled or promoted for noncemented use.
1. All labeling for this device, including package label and labeling included within the package, must prominently state that the device is intended for cemented use only.

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Page 2 - Mr. Frank Maas

1. Any non-cemented fixation of this device is considered investigational and may only be investigated as a significant risk device in accordance with the investigational device exemption (IDE) regulation under 21 CFR, Part 812. All users of the device for noncemented fixation must receive approval from their respective institutional review boards (IRBs) and the Food and Druq Administration (FDA) to conduct the investigation.
  The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practices, 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 Requlations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the current Good Manufacturing Practice requirement, as set forth in the Quality System Requlation (QS) for Medical General regulation (21 CFR Part 820) and that, Devices: through periodic (QS) inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory In addition, FDA may publish further announcements action. 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 Requlations.

This letter will allow you to begin marketing your device as described in your 510(k) premarket notification immediately. An FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and 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 general information on your responsibilities under the Act may be "

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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.gov/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

18972864

510(k) Number (if known):

Device Name: Duration® Stabilized UHMWPE Knee Components

Indications for Use:

SEE NEXT PAGE FOR DURATION® WEAR CLAIMS

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use	X	OR	Over-The-Counter Use
(Per 21 CFR 801.109)

(Division Sign-Off)
Division of General Restorative Devices

510(k) Number	K-972864
---------------	----------

(Optional Format 1-2-96)

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K972864

DURATION® WEAR CLAIMS - KNEE COMPONENTS

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 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 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 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.

Prescription Use
(Per 21 CFR 801.109)

signature

aral Rastnra

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.