K Number
K250677
Date Cleared
2025-04-02

(27 days)

Product Code
Regulation Number
888.3560
Panel
OR
Reference & Predicate Devices
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use
  • 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.
Device Description

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.

AI/ML Overview

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.

§ 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.