(161 days)
Total knee components are indicated for:
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Rheumatoid arthritis.
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Post-traumatic arthritis, osteoarthritis, or degenerative arthritis.
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Failed osteotomies, unicompartmental replacement, or total knee replacement.
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The posterior-stabilized knee system is 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.
LEGION Porous CR Narrow Femoral Components are indicated for use without bone cement and are single use devices.
The Porous Patella and the Porous Tibia Baseplate are indicated for use with or without bone cement, and are single use devices.
The subject Porous Patella is designed to be implanted with or without the use of bone cement for a total knee replacement. The Porous Patella will be made of UHMWPE and Ti-6Al-4V. The metal bone contacting surface and 3 pegs will be made from Ti-6Al-4V, which will be porous, and the bearing surface will be UHMWPE. The bone contacting porous structure will be made of CONCELOC, a material formerly cleared as part of the REDAPT CONCELOC Fully Porous Cup, K1813266. The UHMWPE will be direct compression molded on to the Ti-6AI-4V metal back. The subject Porous Patella will be designed as oval and round resurfacing patellae. The subject device will be press fit into the bone with 3 pegs for initial fixation and provided in various sizes, 26mm-41mm. As a reference, the bearing surface profile of this subject Porous Patella is identical to the Smith & Nephew Genesis II Patella, which was cleared under K042515.
The subject Porous Tibia Baseplate is designed to be implanted with or without the use of bone cement. The Porous Tibia Baseplate is made of Ti-6AI-4V and includes a porous ingrowth surface on the distal face of the implant. The proximal face of the implant includes locking mechanism, dimensions, and size options identical to Smith & Nephew's Journey cemented tibial implant cleared under K121443. The distal side of the implant has a central stem, two large posterior-directed fins, and two smaller anterior-directed fins. There are also two tibial lugs on the anterior half of the implant, one on each of the medial and lateral side of the stem. The subject device includes the same stem length for all sizes, though the fin sizes and locations of the lugs vary between sizes. The subject tibia baseplate includes multiple sizes in both left and right hand versions.
The provided document is a 510(k) premarket notification for a medical device (Porous Patella and Porous Tibia Baseplate). This type of submission focuses on demonstrating substantial equivalence to a legally marketed predicate device rather than undergoing extensive clinical trials or developing complex AI algorithms. Therefore, much of the information requested about AI performance, human reader studies, and ground truth establishment in typical AI/ML medical device submissions is not applicable to this document.
Here's a breakdown of the available information based on your request:
1. Table of acceptance criteria and the reported device performance:
The document describes performance testing used to establish substantial equivalence. The acceptance criteria are implicit in meeting the performance characteristics of the predicate devices.
| Acceptance Criteria (Implicit) | Reported Device Performance (as demonstrated through testing against predicate) |
|---|---|
| Porous Patella: | Porous Patella: |
| - Mechanical performance equivalent to predicate devices (e.g., in tensile strength, shear strength, fatigue, etc.) | - Tensile Strength |
| - Material properties (e.g., pore diameter, coating thickness, roughness, porosity) comparable to predicate. | - Shear Strength |
| - UHMWPE mechanical testing consistent with standard. | - Peg Shear Strength |
| - Nitric passivation of UHMWPE. | - Shear Fatigue Durability testing |
| - Contact Area and Contact Stresses (comparison to predicate) | |
| - Resistance to Subluxation (comparison to predicate) | |
| - Surface Pore Diameter (comparison to predicate) | |
| - Mean Coating Thickness (comparison to predicate) | |
| - Roughness (comparison to predicate) | |
| - Tensile Properties | |
| - Impact Resistance | |
| - Average Porosity (comparison to predicate) | |
| - Mean Void Intercept Length (comparison to predicate) | |
| - Mechanical Testing of Compression molded Polyethylene | |
| - Nitric Passivation of UHMWPE | |
| Porous Tibia Baseplate: | Porous Tibia Baseplate: |
| - Mechanical performance equivalent to predicate devices (e.g., in finite element analysis, fatigue, adhesion). | - Finite Element Analysis for Worst Case Fatigue |
| - Material properties (e.g., chemical composition, pore diameter, coating thickness, porosity, microstructure, roughness). | - Unsupported Baseplate Fatigue |
| - Shear strength of pegs and coating/substrate attachment. | - Cement Adhesion |
| - Tensile attachment strength and substrate properties. | - Intra-plate variability |
| - Abrasion resistance. | - Chemical composition of substrate |
| - Surface Pore Diameter (comparison to predicate) | |
| - Mean coating thickness (comparison to predicate) | |
| - Mean void intercept length (MVIL) (comparison to predicate) | |
| - Average porosity (mean volume percent voids) (comparison to predicate) | |
| - Weld diameter or area | |
| - Microstructure | |
| - Roughness (comparison to predicate) | |
| - Static Shear Strength - baseplate pegs | |
| - Shear fatigue Strength - baseplate pegs | |
| - Shear fatigue - baseplate porous coating/substrate | |
| - Tensile attachment Strength | |
| - Tensile properties of substrate | |
| - Inter-plate variability | |
| - Abrasion Resistance | |
| Sterility: | Sterility: |
| - Meet acceptable endotoxin limits per FDA Guidance. | - Bacterial endotoxin testing completed and met acceptable endotoxin limits as stated in the FDA Guidance, "Submission and Review of Sterility Information in Premarket Notification (510(k)) Submissions for Devices Labeled as Sterile," "Pyrogen and Endotoxins Testing: Questions and Answers," and ANSI/AAMI ST72. |
2. Sample size used for the test set and the data provenance:
- Sample size: The document does not specify a "test set" in the context of clinical data or AI model evaluation. The tests performed are benchtop mechanical and material characterization tests. The specific number of samples for each test (e.g., number of patellae for tensile strength, number of tibia baseplates for fatigue testing) is not provided in this summary.
- Data provenance: Not applicable in the sense of patient data. The provenance for the benchtop tests would be internal laboratory testing by Smith & Nephew.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This is not applicable. The device is a mechanical implant, and its performance is evaluated through engineering and material science benchtop tests, not clinical expert review or AI ground truth establishment.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- This is not applicable. Adjudication methods are relevant for clinical trials or expert review of diagnostic results. This submission relies on benchtop engineering tests.
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 is not applicable. This is a submission for a mechanical implant, not an AI-powered diagnostic device.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- This is not applicable. The device is a mechanical implant, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The "ground truth" for this device's performance is established by engineering and material science standards and benchmarks, generally derived from similar predicate devices and relevant industry standards (e.g., for mechanical properties, material composition, and manufacturing processes).
8. The sample size for the training set:
- This is not applicable. There is no "training set" as this is not an AI/ML device.
9. How the ground truth for the training set was established:
- This is not applicable. There is no "training set" or "ground truth" in the context of AI/ML for this device.
§ 888.3565 Knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis.
(a)
Identification. A knee joint patellofemorotibial metal/polymer porous-coated uncemented 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 is designed to achieve biological fixation to bone without the use of bone cement. This identification includes fixed-bearing knee prostheses where the ultra high molecular weight polyethylene tibial bearing is rigidly secured to the metal tibial base plate.(b)
Classification. Class II (special controls). The special control is FDA's guidance: “Class II Special Controls Guidance Document: Knee Joint Patellofemorotibial and Femorotibial Metal/Polymer Porous-Coated Uncemented Prostheses; Guidance for Industry and FDA.” See § 888.1 for the availability of this guidance.