(27 days)
- Rheumatoid arthritis;
- Post-traumatic arthritis, osteoarthritis, or degenerative arthritis;
- Posterior stabilized and constrained knee systems are also indicated for the treatment of 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.
- Constrained knee systems are designed for use in patients in primary and revision surgery, where the posterior cruciate ligament and one or both of the collateral ligaments (i.e. medial collateral and/or lateral collateral ligament) are incompetent.
The subject insert is a line addition to the LEGION Inserts with JOURNEY Lock (K200407) and has undergone design modifications to provide a new articulating surface that incorporates a flatter lateral plateau and extended medial geometry to match the asymmetry of the tibial baseplate, while maintaining the JOURNEY locking mechanism. The subject LEGION Medial Stabilized Inserts with JOURNEY Lock have a size range of 1-2, 3-4, 5-6, and 7-8mm with thicknesses of 9, 10, 11, 12, 13, 15, 18mm, and come in both left (LT) and right (RT) configurations. The LEGION Medial Stabilized XLPE Inserts with JOURNEY Lock are provided sterile via Ethylene Oxide sterilization and are intended for single use only. The subject inserts are intended to be used with compatible knee systems for total knee arthroplasty in skeletally mature patients with or without bone cement.
I am sorry, but based on the provided FDA 510(k) clearance letter for the LEGION Total Knee System, the document does not contain the specific information required to describe the acceptance criteria and the study that proves the device meets those criteria, especially in the context of an AI/human-in-the-loop performance study.
Here's why the requested information cannot be found in the provided text:
- Device Type: The cleared device, the "LEGION Total Knee System," is a physical medical device (a knee joint prosthesis), not an AI/software device. The 510(k) is for a hardware modification (a new articulating surface for an insert).
- Study Type: The document states, "No clinical testing was performed to support safety and effectiveness of the subject device." The testing mentioned is "bench testing" (Tibiofemoral Constraint Testing and Tibiofemoral Contact Area Testing) which applies to the physical properties of the knee implant.
- AI/Human-in-the-loop: There is no mention of AI, human readers, ground truth establishment by experts, or MRMC studies, as the device is not an AI diagnostic or assistance tool.
Therefore, I cannot provide a table of acceptance criteria and reported device performance related to AI, nor can I answer questions about sample sizes for AI test sets, expert numbers, adjudication methods, MRMC studies, standalone AI performance, or training set details, as these concepts are not applicable to the cleared device as described.
The document focuses on demonstrating substantial equivalence of a new knee implant component to existing, legally marketed predicate devices through material and mechanical performance testing.
FDA 510(k) Clearance Letter - LEGION Total Knee System
Page 1
U.S. Food & Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov
Doc ID # 04017.07.05
April 2, 2025
Smith & Nephew, Inc.
Dana Hartlein
Senior Regulatory Affairs Specialist
7135 Goodlett Farms Pkwy
Cordova, Tennessee 38016
Re: K250677
Trade/Device Name: LEGION Total Knee System
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: March 6, 2025
Received: March 6, 2025
Dear Dana Hartlein:
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 (the 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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.
April 2, 2025
Smith & Nephew, Inc.
Dana Hartlein
Senior Regulatory Affairs Specialist
7135 Goodlett Farms Pkwy
Cordova, Tennessee 38016
Re: K250677
Trade/Device Name: LEGION Total Knee System
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: March 6, 2025
Received: March 6, 2025
Dear Dana Hartlein:
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 (the 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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.
U.S. Food and Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov
Page 2
K250677 - Dana Hartlein Page 2
Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
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 Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems.
For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-
Page 3
K250677 - Dana Hartlein Page 3
assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Lixin Liu -S
Lixin Liu, Ph.D
Assistant Director
DHT6A: Division of Joint Arthroplasty Devices
OHT6: Office of Orthopedic Devices
Office of Product Evaluation and Quality
Center for Devices and Radiological Health
Enclosure
Page 4
Indications for Use
Please type in the marketing application/submission number, if it is known. This textbox will be left blank for original applications/submissions. K250677
Please provide the device trade name(s). LEGION Total Knee System
Please provide your Indications for Use below.
- Rheumatoid arthritis;
- Post-traumatic arthritis, osteoarthritis, or degenerative arthritis;
- Posterior stabilized and constrained knee systems are also indicated for the treatment of 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.
- Constrained knee systems are designed for use in patients in primary and revision surgery, where the posterior cruciate ligament and one or both of the collateral ligaments (i.e. medial collateral and/or lateral collateral ligament) are incompetent.
Please select the types of uses (select one or both, as applicable).
☑ Prescription Use (Part 21 CFR 801 Subpart D)
☐ Over-The-Counter Use (21 CFR 801 Subpart C)
LEGION Medial Stabilized Insert with JOURNEY Lock Page 9 of 32
Page 5
510(k) Summary
510(k) #: K250677
Prepared on: 2025-04-01
Contact Details
21 CFR 807.92(a)(1)
| Field | Value |
|---|---|
| Applicant Name | Smith & Nephew, Inc. |
| Applicant Address | 7135 Goodlett Farms Pkwy Cordova TN 38016 United States |
| Applicant Contact Telephone | 484-557-4768 |
| Applicant Contact | Ms. Dana Hartlein |
| Applicant Contact Email | dana.hartlein@smith-nephew.com |
Device Name
21 CFR 807.92(a)(2)
| Field | Value |
|---|---|
| Device Trade Name | LEGION Total Knee System |
| Common Name | Total Knee Prosthesis |
| Classification Name | Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis |
| Regulation Number | 888.3560 |
| Product Code(s) | JWH |
Legally Marketed Predicate Devices
21 CFR 807.92(a)(3)
| Predicate # | Predicate Trade Name (Primary Predicate is listed first) | Product Code |
|---|---|---|
| K200407 | LEGION CR High Flex Insert with JRNY Lock | JWH |
| K200407 | LEGION Deep Dish Insert with JRNY Lock | JWH |
| K211671 | JOURNEY II Medial Dished XLPE Articular Insert | JWH |
| K220896 | Legion Inserts with JRNY Lock | JWH |
Device Description Summary
21 CFR 807.92(a)(4)
The purpose of this Special 510(k) is to notify FDA of our intent to market the Smith & Nephew LEGION Medial Stabilized Insert with JOURNEY Lock as part of the LEGION Total Knee System. The subject insert is a line addition to the LEGION Inserts with JOURNEY Lock (K200407) and has undergone design modifications to provide a new articulating surface that incorporates a flatter lateral plateau and extended medial geometry to match the asymmetry of the tibial baseplate, while maintaining the JOURNEY locking mechanism. The subject LEGION Medial Stabilized Inserts with JOURNEY Lock have a size range of 1-2, 3-4, 5-6, and 7-8mm with thicknesses of 9, 10, 11, 12, 13, 15, 18mm, and come in both left (LT) and right (RT) configurations. The LEGION Medial Stabilized XLPE Inserts with JOURNEY Lock are provided sterile via Ethylene Oxide sterilization and are intended for single use only. The subject inserts are intended to be used with compatible knee systems for total knee arthroplasty in skeletally mature patients with or without bone cement.
Intended Use/Indications for Use
21 CFR 807.92(a)(5)
- Rheumatoid arthritis;
- Post-traumatic arthritis, osteoarthritis, or degenerative arthritis;
- Posterior stabilized and constrained knee systems are also indicated for the treatment of unicompartmental replacement or total knee replacement;
K250677 Page 1 of 2
Page 6
- 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.
- Constrained knee systems are designed for use in patients in primary and revision surgery, where the posterior cruciate ligament and one or both of the collateral ligaments (i.e. medial collateral and/or lateral collateral ligament) are incompetent.
Indications for Use Comparison
21 CFR 807.92(a)(5)
The subject LEGION Total Knee System has similar indications for use and the same intended use as the predicates.
Technological Comparison
21 CFR 807.92(a)(6)
The overall function, intended use, material composition, manufacturing processes, and packaging for the LEGION Medial Stabilized Insert with JOURNEY Lock is identical to the commercially available predicate devices identified above (K200407). The new LEGION Medial Stabilized Insert with JOURNEY Lock introduces a new articulating surface compared to the primary predicate LEGION CR High Flex Insert with JRNY Lock. The new articulating surface is similar to that of the secondary predicate, the JOURNEY II Medial Dished XLPE Articular Insert (K211671).
Non-Clinical and/or Clinical Tests Summary & Conclusions
21 CFR 807.92(b)
The following bench testing was performed for the LEGION Medial Stabilized Insert with JOURNEY Lock:
- Tibiofemoral Constraint Testing per ASTM F1223-20, and ISO 21536.
- Tibiofemoral Contact Area Testing per ISO 21536.
No clinical testing was performed to support safety and effectiveness of the subject device.
The results of the constraint and contact area testing demonstrated acceptable outcomes. The results demonstrate that the LEGION Medial Stabilized Insert with JOURNEY Lock is substantially equivalent to the currently marketed predicate.
K250677 Page 2 of 2
§ 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.