NATURAL-KNEE II CEMENTED MODULAR TIBIAL BASEPLATE

K023528 · Centerplus Orthopedics, Inc. · JWH · Jan 17, 2003 · Orthopedic

Device Facts

• Record ID: K023528
• Device Name: NATURAL-KNEE II CEMENTED MODULAR TIBIAL BASEPLATE
• Applicant: Centerplus Orthopedics, Inc.
• Product Code: JWH · Orthopedic
• Decision Date: Jan 17, 2003
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 888.3560
• Device Class: Class 2
• Attributes: Therapeutic

Intended Use

The Natural-Knee II Cemented Modular Tibial Baseplate is intended for cemented use only in total knee arthroplasty for treatment of the following conditions: - Patient conditions of noninflammatory degenerative joint disease (NIDJD), e.g., 1. avascular necrosis, osteoarthritis, and inflammatory joint disease (IJD), e.g., rheumatoid arthritis. - 2. Correctable valgus-varus deformity and moderate flexion contracture. - 3. Those patients with failed previous surgery where pain, deformity or dysfunction persists.

Device Story

Modular tibial baseplate component for total knee arthroplasty; manufactured from cast CoCr alloy. Designed for cemented use; features grit-blasted cement pockets on inferior surface for fixation. Asymmetric design; mates with Natural-Knee/Natural-Knee II tibial inserts via snap-lock mechanism. Includes central slot for constrained/revision insert reinforcement pins. Cruciform stem boss accepts various Natural-Knee II stems (smooth/fluted straight, fluted offset) via inner female taper; secondary fixation via attachment screw. Optional stem hole plug available. Used by orthopedic surgeons in clinical/OR settings to restore joint function and alleviate pain in patients with degenerative or inflammatory joint disease.

Clinical Evidence

No clinical data provided; substantial equivalence based on design, material, and intended use comparisons to legally marketed predicate devices.

Technological Characteristics

Material: Cast CoCr alloy (ASTM F75). Design: Asymmetric, nonporous, modular tibial baseplate. Features: Grit-blasted cement pockets, cruciform stem boss with inner female taper, snap-lock interface for tibial inserts. Energy source: None (mechanical). Connectivity: None. Sterilization: Not specified.

Indications for Use

Indicated for patients undergoing total knee arthroplasty requiring cemented fixation. Conditions include noninflammatory degenerative joint disease (avascular necrosis, osteoarthritis), inflammatory joint disease (rheumatoid arthritis), correctable valgus-varus deformity, moderate flexion contracture, and failed previous surgery with persistent pain, deformity, or dysfunction.

Regulatory Classification

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).

Predicate Devices

• Natural-Knee II System CoCr Tibial Baseplate
• Stryker/Osteonics/Howmedica Duracon
• Stryker/Osteonics/Howmedica Scorpio
• Wright Medical Advance

Submission Summary (Full Text)

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## JAN 1 7 2003

02 3528
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#### 510(k) SUMMARY

In accordance with the Food and Drug Administration Rule to implement provisions of the Safe Medical Devices Act of 1990 and in conformance with 21 CFR 807, this is to serve as a Summary of Safety and Effectiveness for the Centerpulse Orthopedics Natural-Knee® II Cemented Modular Tibial Baseplate.

| Manufacturer: | Centerpulse Orthopedics Inc.<br>9900 Spectrum Drive<br>Austin, Texas 78717<br>[phone] |
|-------------------------|---------------------------------------------------------------------------------------------------------------------|
| Date: | October 18, 2002 |
| Contact Person: | Mitchell A. Dhority<br>Manager, Regulatory Affairs |
| Classification Name: | 21 CFR Part 888.3560 - Knee joint patellofemorotibial<br>polymer/metal/polymer semi-constrained cemented prosthesis |
| Common/Usual Name: | Nonporous, Cemented Modular Tibial Baseplate |
| Trade/Proprietary Name: | Natural-Knee® II Cemented Modular Tibial Baseplate |

#### PRODUCT DESCRIPTION

The Natural-Knee II Cemented Tibial Baseplate is an asymmetrically oriented (e.g. both left and right orientations), nonporous component manufactured from cast CoCr alloy (ASTM F75).

The baseplate is designed to mate with all previously cleared tibial insert components of the Natural-Knee/Natural-Knee II System via capture features on the anterior rim and posterior plateau rims. As such, the baseplate incorporates the snap lock design from the previously cleared Natural-Knee II tibial baseplates. A slot has also been incorporated into the center of the base of the tray to allow for seating of the metal reinforcement pin of the previously cleared Natural-Knee II Constrained/Revision tibial inserts.

The cruciform stem portion of the baseplate is designed to accept one of the previously cleared stems used with the Natural-Knee II System (smooth straight, fluted straight, fluted offset). The baseplate stem boss incorporates the stem connection design of the previously cleared Natural-Knee II Revision Femoral Component. This connection design includes an inner female taper for primary attachment of the stem. Supplemental secondary stem fixation may be achieved by placing the stem attachment screw through the recessed hole in the baseplate and into the screw hole in the stem. The rounded, baseplate stem hole plug designed for use with this component may also be used if a stem is not desired. Unlike the stems, the plug does not possess a taper and is attached to the baseplate solely via the stem attachment screw previously described.

The inferior surface of the baseplate has cement pockets that are grit blasted to enhance cement fixation. The three fins of the stem boss aid in maintaining rotational stability.

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K02352P
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#### SPECIFIC DIAGNOSTIC INDICATIONS

The Natural-Knee II Cemented Modular Tibial Baseplate is intended for cemented use only in total knee arthroplasty for treatment of the following conditions:

- Patient conditions of noninflammatory degenerative joint disease (NIDJD), e.g., 1. avascular necrosis, osteoarthritis, and inflammatory joint disease (IJD), e.g., rheumatoid arthritis.
- 2. Correctable valgus-varus deformity and moderate flexion contracture.
- 3. Those patients with failed previous surgery where pain, deformity or dysfunction persists.

### SUBSTANTIAL EQUIVALENCE

The Natural-Knee II Cemented Tibial Baseplate is similar to the following commercially available devices in terms of general design, materials, intended use and indications for use:

- Natural-Knee II System CoCr Tibial Baseplate ●
- Stryker/Osteonics/Howmedica Duracon .
- Stryker/Osteonics/Howmedica Scorpio .
- Wright Medical Advance ●

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized eagle with three horizontal lines forming its body and two curved lines representing its legs. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circular pattern around the eagle.

Public Health Service

JAN 1 7 2003

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Mr. Mitchell A. Dhority Manager, Regulatory Affairs Centerpulse Orthopedics, Inc. 9900 Spectrum Drive Austin, Texas 78717

Re: K023528

Trade/Device Name: Natural-Knee® II Cemented Modular Tibial Baseplate Regulation Number: 21 CFR 888.3560 Regulation Name: Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis Regulatory Class: Class II Product Code: JWH Dated: October 18, 2002 Received: October 21, 2002

Dear Mr. Mitchell:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate 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) that do not require approval of a premarket approval application (PMA). 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 (PMA), 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 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does no: mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set

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Page 2 – Mr. Mitchell A. Dhority

forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050. This letter will allow you to begin marketing your device as described in your Section 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), please contact the Office of Compliance at [phone]. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number [phone] or [phone] or at its Internet address

http://www.fda.qov/cdrh/dsma/dsmamain.html

Sincerely yours,
Mark A Millerson

Celia M. Witten, Ph.D., M.D. Director

Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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510(k) Number (if known):

Device Name: Natural-Knee II System Cemented Modular Tibial Baseplate

# Indications for Use:

The Natural-Knee II Cemented Modular Tibial Baseplate is intended for cemented use only in total knee arthroplasty for treatment of the following conditions:

KO23528

- 1. Patient conditions of noninflammatory degenerative joint disease (NIDJD), e.g., avascular necrosis, osteoarthritis, and inflammatory joint disease (IJD), e.g., rheumatoid arthritis.
- 2. Correctable valgus-varus deformity and moderate flexion contracture.
- Those patients with failed previous surgery where pain, deformity or dysfunction persists. 3.

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use

OR

Over-The-Counter Use

(Optional Format 1-2-96)

Mark N Mulkerson

Division Sign-Of Division of General, Restorative and Neurological De

510(k) Number K023