Total knee components are indicated for rheumatoid arthritis; post-traumatic arthritis, osteoarthritis, or degenerative arthritis in older patients whose age, weight, and activity level are compatible with an adequate long-term result; failed osteotomies, unicompartmental replacement, or total knee replacement. Posterior stabilized knee systems are designed for use in patients in primary and revision surgery, where the anterior and posterior cruciate ligaments are absent or incompetent and the collateral ligaments remain intact. Smith & Nephew, Inc. Legion Primary Knee components are indicated for use only with cement and are single use devices.

Device Description

Subject of this Traditional 510(k) Premarket Notification is a request for long-term in vitro wear claims for the Smith & Nephew, Inc. Legion Primary Knee System. The wear claims will be made for the use of a Legion Primary Oxinium femoral component coupled with a 7.5 Mrad cross-linked polyethylene (XLPE) articular insert. The Legion Primary Knee System consists of existing total knee implant devices, and it is important to note that there are no new total knee components being introduced as a result of this Traditional 510(k) premarket notification.

AI/ML Overview

This document, K093746, is a Traditional 510(k) Premarket Notification for wear claims for the LEGION® Primary Knee System, specifically focusing on the performance of an OXINIUM® femoral component coupled with a 7.5 Mrad cross-linked polyethylene (XLPE) articular insert. It is important to note that this submission does not introduce new total knee components but rather seeks clearance for long-term wear claims for an existing system.

Here's an analysis of the provided information based on your requested criteria:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Implicit for wear claims)	Reported Device Performance
Low wear characteristics compared to a control total knee system in long-term laboratory testing.	The OXINIUM®/XLPE bearing couple exhibited low wear characteristics in long-term in vitro laboratory testing.

Explanation of "Acceptance Criteria": The document doesn't explicitly state numerical acceptance criteria (e.g., "wear must be less than X mg"). Instead, the acceptance is based on demonstrating "low wear characteristics" in comparison to a control device in an in vitro knee simulator. The FDA clearance implies that this comparative performance was deemed acceptable for the wear claims.

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

Sample Size: The document does not specify the exact sample size (number of femurs, inserts, or test configurations) used in the in vitro knee simulator wear testing. It refers to "long-term laboratory testing."
Data Provenance: The data is from in vitro knee simulator wear testing, which is a laboratory setting. There is no information provided about the country of origin, but given the company (Smith & Nephew, Inc.) is based in Memphis, Tennessee, USA, it's reasonable to infer the testing was likely conducted in the US or by a US-based laboratory. The testing is not clinical data; it is in vitro.

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

Ground Truth Experts: Not applicable. For in vitro mechanical wear testing, "ground truth" is established by the validated testing methodology and measurement of wear (e.g., gravimetric assessment of polyethylene mass loss). Human experts in the sense of clinicians or radiologists are not involved in establishing the "ground truth" for this type of performance testing.

4. Adjudication Method for the Test Set

Adjudication Method: Not applicable. This refers to the process by which disagreements among human experts in clinical or imaging studies are resolved. As the performance data is from in vitro mechanical testing, there are no human expert judgments or adjudication processes involved in the data generation.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

MRMC Study: No. An MRMC study involves multiple human readers assessing medical cases, often with and without AI assistance, to measure diagnostic performance. The provided document is about in vitro wear performance of a knee implant, not diagnostic imaging, and does not involve human readers.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Standalone Study: Yes, in a conceptual sense within its context. The "device performance" in this submission refers to the in vitro mechanical performance of the knee joint components themselves, operating in a simulator without human intervention. This is a "standalone" evaluation of the mechanical system's wear characteristics. There is no "algorithm" in the traditional sense of an AI model, but the mechanical system's performance is assessed independently.

7. The Type of Ground Truth Used

Type of Ground Truth: The ground truth for wear performance in this in vitro study is based on direct physical measurement of material loss (e.g., gravimetric wear, linear penetration) from the components during standardized knee simulator testing, according to established test protocols (e.g., ISO standards for knee wear testing, though not explicitly cited here, are typical for such studies). This is considered an objective, quantifiable physical output.

8. The Sample Size for the Training Set

Training Set Sample Size: Not applicable. This submission concerns in vitro mechanical wear testing of a physical device, not an AI/ML algorithm that requires a "training set."

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

Training Set Ground Truth: Not applicable, as there is no training set for this type of device performance evaluation.

Summary

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K093746

Summary of Safety and Effectiveness VERILAST® Wear Claims for the LEGION* Primary Knee System Smith & Nephew, Inc.

Contact Person and Address

Jason Sells Manager, Regulatory Affairs Smith & Nephew, Inc. Orthopaedic Division 1450 East Brooks Road Memphis, Tennessee 38116 T (901) 399-5520

Date of Summary: April 14, 2010

4/14/2010

Name of Device: LEGION® Primary Knee System

Common Name: Total Knee Prosthesis

Device Classification Name and Reference: 21 CFR 888.3560 Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis

Device Class: Class II

Panel Code: Orthopaedics/87 JWH

Predicate Devices: Genesis II & Profix Zirconium Femoral Knee Components (K962557); and Crosslinked Polyethylene Articular Inserts (K071071)

Device Description

Intended Use

Total knee components are indicated for rheumatoid arthritis; post-traumatic arthritis, or degenerative arthritis in older patients whose age, weight, and activity level are compatible with an adequate long-term result; failed osteotomies, unicompartmental replacement, or total knee replacement. Posterior stabilized knee systems are designed for use in patients in primary and revision surgery, where the anterior and posterior cruciate ligaments are absent or incompetent and the collateral ligaments remain intact. Smith & Nephew, Inc. Legion Primary Knee components are indicated for use only with cement and are single use devices.

Performance Data

In vitro knee simulator wear testing provided in the submission demonstrated that the OXINIUM?/XLPE bearing couple exhibited low wear characteristics in long-term laboratory testing as compared to a control total knee system. The results of in-vitro wear simulation testing have not been proven to quantitatively predict clinical wear performance.

Clinical data was not needed to support the safety and effectiveness of the subject device.

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Substantial Equivalence Information

The Legion Primary Knee System consists of existing total knee implants currently marketed by Smith & Nephew. The femoral implant components are substantially equivalent to the Genesis II Oxinium femoral components cleared via K962557. The following, minor modifications were made to the Genesis II Oxinium femoral components in order to develop the subject devices:

l Increased the thickness of the medial posterior condyle to match that of the lateral posterior condyle
Addition of threaded screw holes for wedge attachment (posterior stabilized design only) I
Addition of anterior wall to femoral box geometry (posterior stabilized design only) ■
트 Increased in height of femoral box geometry (posterior stabilized design only)

The subject femoral components are used with existing Legion articular inserts' cleared via K071071.

Conclusion

As previously noted, this Traditional 510(k) Premarket Notification is being submitted to request clearance for long-term wear claims for the Smith & Nephew, Inc. Legion Primary Knee System. As no new total knee components are being introduced as a result of this premarket notification, the devices are substantially equivalent to knee components currently marketed under K962557 and K071071.

1 The Genesis II cross-linked polyethylene IXLPE) articular inserts cleared via K071071 are marketed by Smith & Nephew under the Legion brand name.

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Image /page/2/Picture/1 description: The image shows the logo for the Department of Health & Human Services. The logo is a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is an abstract image of an eagle.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Room -WO66-G609 Silver Spring, MD 20993-0002

APR 1 4 2010

Smith & Nephew, Inc. % Mr. Jason Sells 1450 E Brooks Road Memphis. Tennessee 38116

Re: K093746

Trade/Device Name: LEGION Primary Knee System

Regulation Number: 21 CFR 888.3560 Regulation Name: Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis

Regulatory Class: II

Product Code: JWH Dated: April 8, 2010 Received: April 9, 2010

Dear Mr. Sells:

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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to 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 not 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); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set

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Page 2 - Mr. Jason Sells

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.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to http://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm115809.htm for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm.

Sincerely vours.

Barbara Brem

Mark N. Melkerson Director Division of Surgical, Orthopedic 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). K093746

Device Name: LEGION® Primary Knee System

Indications for Use:

Prescription Use x AND/OR (Part 21 CFR 801 Subpart D)

Over-The-Counter Use (21 CFR 807 Subpart C)

IPLEASE DO NOT WRITE BELOW THIS LINE – CONTINUE ON ANOTHER PAGE IF NEEDED]

Concurrence of CDRH, Office of Device Evaluation (ODE)

Anita for MXM

bedic. and Rest

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510(k) Number K093746

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.