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The Legion Cones are intended to be used with the Legion Revision and Legion Hinge knee systems. The Legion Cones are indicated for the following:

1. Rheumatoid arthritis.

2. Post-traumatic arthritis, osteoarthritis, or degenerative arthritis.

3. Failed osteotomies, unicompartmental replacement, or total knee replacement.

4. 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.

5. 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 collateral ligament) are incompetent.

6. Hinge 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 collateral ligament) are absent of incompetent.

These are single use implants and are intended for use with and without bone cement.

Subject of this Traditional premarket notification is the Smith & Nephew Legion™ Cone System. The Smith & Nephew Legion Cone System consists of porous coated tibial and femoral augments to address cavitary defects in the proximal tibia or distal femur. The system will also include the necessary instrumentation for the surgeon to prepare the tibia and femur for implantation of the augments.

The components of the Smith & Nephew Legion Cone System are as follows:

• Titanium alloy (Ti-6Al-4V) tibial cones of 2 heights and 7 sizes .
• · Titanium alloy (Ti-6Al-4V) hand-specific femoral cones of 1 height and 7 sizes

The Leqion Tibial and Femoral Cones are a one piece, conically shaped device with cannulation all the way through the cone which allows fixation to the Legion Revision and Legion Hinge tibial baseplates, femoral components, offset couplers, augments/wedges, and stem constructs.

The Legion Tibial and Femoral Cones are similar to the primary predicate Zimmer Trabecular™ Metal Tibial and Femoral Cone Augments cleared via premarket notification K053340. The Legion Tibial Cones will be available in heights of 25mm (short) and 40mm (long) and inner diameters (ID) of 18mm-30mm, in 2mm increments. The Legion Femoral Cones will be available in a height of approximately 35mm and inner diameters of 18mm-30mm, in 2mm increments. The Legion Femoral Cones will be provided in left and right orientations. The subject tibial and femoral cones are manufactured from forged titanium alloy (Ti-6Al-4V) that conforms to ASTM F 1472. The subject tibial and femoral cones also have an external asymmetric (Stiktite™) porous coating specification identical to the porous coating of the reference predicate Smith & Nephew SMF™ Hip Stems cleared via premarket notifications K080625. K103256, and K123012. The interior side of the subject cones has a grit-blasted surface specification for cement adhesion identical to the gritblasted surface of reference predicate Smith & Nephew Genesis II Total Knee System cement-on-augment devices cleared via premarket notification K951987.

The provided document is a 510(k) premarket notification for a medical device called the "Legion Cone System." This type of document is a submission to the FDA to demonstrate that the device is substantially equivalent to a legally marketed predicate device. It typically does not contain information about acceptance criteria for a study proving device performance in the way that a clinical trial or a formal performance study for an AI/CADe device would.

Instead, for this type of device (knee prosthesis components), the "acceptance criteria" are generally met through mechanical testing and a comparison to predicate devices, demonstrating substantial equivalence in design, materials, and intended use. The "study" proving it meets acceptance criteria is primarily a series of mechanical tests and a predicate comparison.

Therefore, I will interpret your request in the context of this document type, focusing on the mechanical testing performed and the comparison to predicate devices, rather than a clinical study evaluating AI performance.

Here's the breakdown of the information you requested based on the provided text:

1. A table of acceptance criteria and the reported device performance

The document does not explicitly list "acceptance criteria" in a quantitative table with specific pass/fail values for each test. Instead, it states that a "mechanical evaluation" was conducted and that this evaluation "demonstrated that there are no new issues related to the safety or effectiveness of the subject devices." This implies that the results of these tests were considered acceptable when compared to established standards for such devices or to the performance of predicate devices.

Specific Mechanical Tests Conducted:

• Fatigue Strength
• Push-Out Strength
• Torsional Shear
• Tensile Attachment Strength

The document states, "A review of testing has demonstrated that there are no new issues related to the safety or effectiveness of the subject devices." This indicates the device passed these implied criteria by performing adequately in these mechanical tests.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

This information is not provided in the document. The "tests" mentioned are mechanical tests on device components, not typically "data sets" in the context of AI/software or clinical trials. Therefore, concepts like country of origin or retrospective/prospective do not apply. The sample sizes for the mechanical tests (e.g., how many cones were tested for fatigue) are not disclosed.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

This information is not applicable/not provided. The "ground truth" for a mechanical test is typically determined by the physics and engineering principles governing the test and measurement. There isn't an "expert" establishing ground truth in the way a clinical expert would for a diagnostic image. The "experts" involved would be the engineers and scientists conducting and analyzing the mechanical tests.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

This information is not applicable/not provided. Adjudication methods like 2+1 are used in clinical studies, especially for ground truth establishment in ambiguous cases. This is not relevant for mechanical testing of an orthopedic implant.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

This information is not applicable. An MRMC study or AI assistance is not relevant to the Legion Cone System, which is a physical implant component, not an AI/software device. The document explicitly states: "Clinical data was not needed to support the safety and effectiveness of the subject devices."

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

This information is not applicable. This refers to AI algorithm performance studies, which are not relevant to this physical orthopedic implant.

7. The type of ground truth used (expert concensus, pathology, outcomes data, etc)

For the mechanical tests, the "ground truth" is established by the physical and engineering measurements against accepted standards and the performance of predicate devices. There is no biological "ground truth" like pathology or outcomes data from patients in this premarket notification for a mechanical device.

8. The sample size for the training set

This information is not applicable/not provided. There is no "training set" in the context of mechanical testing for a physical implant. This concept applies to machine learning models.

9. How the ground truth for the training set was established

This information is not applicable/not provided. As there is no training set mentioned, the establishment of its ground truth is not relevant.

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