Total knee components are indicated for rheumatoid arthritis; post-traumatic arthritis, osteoarthritis, or degenerative arthritis; 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 incompetent and the collateral ligaments remain intact.

Smith & Nephew, Inc. Legion Narrow Oxinium C/R and P/S Femoral Components are indicated for use only with cement and are single use only devices.

Device Description

The implant devices described in this premarket notification are comprised of Legion Narrow Oxinium Cruciate Retaining (CR) and Posterior Stabilized (PS) Femoral Components. All described implant components are manufactured from oxidized zirconium alloy material (trade name: Oxinium). The subject devices are available in the following configurations and sizes:

Device Type	Hand	Available Sizes
Legion Narrow Oxinium CR Femoral Components	Left	3, 4, 5 and 6
Legion Narrow Oxinium CR Femoral Components	Right	3, 4, 5 and 6
Legion Narrow Oxinium PS Femoral Components	Left	3, 4, 5 and 6
Legion Narrow Oxinium PS Femoral Components	Right	3, 4, 5 and 6

Device specific instruments are also described in this premarket notification in select sections and exhibits.

AI/ML Overview

The provided document describes a 510(k) Premarket Notification for a medical device, specifically total knee prosthesis femoral components. This type of filing focuses on demonstrating substantial equivalence to existing legally marketed devices, rather than proving a new device meets specific quantitative acceptance criteria through clinical studies.

Therefore, the input you've provided does not contain the information requested regarding acceptance criteria studies, such as:

A table of acceptance criteria and reported device performance.
Sample sizes, data provenance, number of experts for ground truth, or adjudication methods for test sets.
MRMC comparative effectiveness studies or human reader improvement data.
Standalone algorithm performance.
Types of ground truth used.
Training set sample size or how its ground truth was established.

Instead, the document details:

A. Acceptance Criteria and Study Approach (Implicit through Substantial Equivalence):

Acceptance Criteria (Implicit): The primary acceptance criterion for a 510(k) submission is demonstrating substantial equivalence to a predicate device. This is achieved by showing that the new device has:
- The same intended use.
- The same technological characteristics, or if there are different technological characteristics, that these differences do not raise different questions of safety and effectiveness.
- The new device is as safe and effective as the predicate device.
Study That "Proves" Device Meets Criteria: The "study" in this context is a preclinical testing program designed to show that the new device's critical performance aspects are comparable to or better than the predicate devices. This isn't about meeting a specific numerical performance threshold for a new, novel characteristic, but rather confirming that the device performs as expected given its design and materials, and in a manner similar to previously cleared devices.

B. Details from the Provided Document:

Table of Acceptance Criteria and Reported Device Performance: This information is not explicitly provided in a table format with quantitative thresholds. The document states that the new device shares "very similar or identical Indications of Use, intended use, are manufactured from similar or identical materials, and incorporate very similar technological design characteristics" to its predicates. The preclinical testing described aims to support this similarity rather than report against specific numerical acceptance criteria.
Sample Size Used for the Test Set and Data Provenance: Not applicable/not provided. The preclinical tests mentioned (Tibiofemoral Constraint, Tibiofemoral Contact Area, Patellofemoral Subluxation Testing) are laboratory mechanical tests, not clinical studies involving human patients or retrospective/prospective data from specific countries. The sample size for these mechanical tests is typically determined by engineering standards and statistical power for material and design performance, but is not specified here.
Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications: Not applicable/not provided. Mechanical integrity and performance are established through objective physical measurements and engineering analysis, not expert clinical consensus for "ground truth" in the diagnostic sense.
Adjudication Method for the Test Set: Not applicable/not provided. As this is not a diagnostic device involving human interpretation, an adjudication method is not relevant.
Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study: No, an MRMC study was not done. This device is a total knee prosthesis, a mechanical implant, not an imaging diagnostic AI or software.
Standalone Performance Study: The "preclinical testing" mentioned (Tibiofemoral Constraint, Tibiofemoral Contact Area, Patellofemoral Subluxation Testing) represents standalone performance evaluations for the mechanical characteristics of the device. However, this is not a "standalone algorithm performance" in the AI sense.
Type of Ground Truth Used: For the preclinical tests, the "ground truth" is based on the physical properties and mechanical behavior of the device components as measured by standardized testing methods and engineering principles. There is no pathology, outcomes data, or expert consensus used for ground truth in this context.
Sample Size for the Training Set: Not applicable/not provided. This is a medical device (implant), not an AI algorithm requiring a training set in the machine learning sense.
How the Ground Truth for the Training Set was Established: Not applicable/not provided.

In summary: The provided 510(k) summary focuses on demonstrating substantial equivalence of a knee implant to existing devices through comparison of design, materials, intended use, and preclinical mechanical testing. It does not involve the type of clinical trial or AI performance evaluation that would require the specific "acceptance criteria and study" details you've requested.

Summary

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510(k) Summary of Safety and Effectiveness Legion Narrow Oxinium CR and PS Femoral Components and Device Specific Instruments

Submitted By:	Smith & Nephew, Inc.Orthopaedics1450 Brooks RoadMemphis, TN 38116
Date:	October 3, 2011
Contact Person:	David Henley, Regulatory Affairs Project ManagerTel: (901) 399-6487 Fax: (901) 566-7079
Proprietary Name:	Legion Narrow Oxinium CR and PS FemoralComponents and Instruments
Common Name:	Total Knee Prosthesis
Classification Name and Reference:	21 CFR 888.3560, Knee joint patellofemorotibialpolymer/metal/polymer semi-constrained cementedprosthesis
Device Class	Class II
Device Product Code and Panel Code:	JWH / Orthopedics / 87

Device Description:

Device Type	Hand	Available Sizes
Legion Narrow Oxinium CR Femoral Components	Left	3, 4, 5 and 6
Legion Narrow Oxinium CR Femoral Components	Right	3, 4, 5 and 6
Legion Narrow Oxinium PS Femoral Components	Left	3, 4, 5 and 6
Legion Narrow Oxinium PS Femoral Components	Right	3, 4, 5 and 6

Device specific instruments are also described in this premarket notification in select sections and exhibits.

Intended Use:

Total knee components are indicated for rheumatoid arthritis; post-traumatic arthritis, or degenerative arthritis; 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 incompetent and the collateral ligaments remain intact.

Smith & Nephew, Inc. Legion Narrow Oxinium CR and PS Femoral Components are indicated for single use only and for use only with bone cement.

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Technological Characteristics:

Components comprising Legion Narrow Oxinium CR and PS Femoral Components are verv similar to the legally marketed devices listed below. When compared to the predicates, the proposed devices share very similar or identical Indications for Use, intended use, are manufactured from similar or identical materials, and incorporate very similar technological design characteristics.

Substantial Equivalence Information:

When compared to the implant and device specific instrument predicate devices listed below. substantial equivalence is based on similarities with regard to overall indications for use, material composition, and technological design characteristics.

· Genesis II Total Knee System K951987
· Genesis II and Profix Zirconium Femoral Components K962557
· Legion Primary Knee System K093746

Preclinical Testing:

To further support a determination of substantial equivalence, various types of pre-clinical testing were conducted on the subject, implantable devices in comparison against one or more of the previously cleared predicate devices described above. The specific types of pre-clinical testing included:

· Tibiofemoral Constraint Testing of femorals against interfacing polyethylene articular insert components seated in appropriate metal tibial bases in A/P Draw, M/L Shear and rotary laxity (R/L)
· Tibiofemoral Contact Area Testing of femorals against interfacing polyethylene articular insert components seated in appropriate metal tibial bases
Patellofemoral Subluxation Testing of the femoral to determine the amount of resistance to lateral subluxation of the patellofemoral interface

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Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized eagle or bird-like symbol with three curved lines forming its body and head. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" is arranged in a circular fashion around the bird symbol.

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

DEC 2 0 2011

Smith & Nephew, Inc. Orthopaedics Division % Mr. David Henley Regulatory Affairs Project Manager 7135 Goodlet Farms Parkway Cordova, Tennessee 38016

Re: K112941

Trade/Device Name: Legion Narrow Oxinium Cruciate Retaining (CR) and Posterior Stabilized (PS) Femoral Components and Device Specific Instruments 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: October 3, 2011 Received: October 4, 2011

Dear Mr. Henley:

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.

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Page 2 - Mr. David Henley

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 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 yours.

Erine Keith

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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Premarket Notification

Indications for Use Statement

510(k) Number (if known): _ K || 29 H |

Device Name: Legion Narrow Oxinium C/R and P/S Femoral Components

Indications for Use:

Smith & Nephew, Inc. Legion Narrow Oxinium C/R and P/S Femoral Components are indicated for use only with cement and are single use only devices.

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

Over-the-Counter Use (Part 21 CFR 807 Subpart C)

(Please do not WRITE BELOW THIS LINE – CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

for Mark Melkerson

(Division Sign-Off) (Division Sign-On), Orthopedic, Division of Restorative Devices

K112941

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.