(156 days)
Total Knee components are indicated for rheumatoid arthritis; post-traumatic arthritis, osteoarthritis, or degenerative arthritis for use in primary and revision surgeries. Posterior stabilized knee systems are designed for use in patients in primary and revision surgery, where the anterior and posterior cruciate ligaments are absent or incompetent and the collateral ligaments remain intact. Constrained Knee Systems are designed for use in patients in primary and revision surgeries, where the posterior cruciate ligament and one or both of the colateral ligaments (i.e. medial cruciate ligament and one or both of the collateral ligaments) are absent or inadequate. Smith & Nephew, Inc. Crosslinked Polyethylene Articular Inserts are single use devices. The indications for each device system are identical to the indications for each cleared predicate knee system
The intended use, base material, and design specifications of the Smith & Nephew Crosslinked Polyethylene articular inserts for the Journey and Genesis II knee systems are the same as subject identical components fabricated from conventional non-Crosslinked Ultra High Molecular Weight Polyethylene. The devices subject to this premarket notification have been Crosslinked by a proprietary process. As a result, the polymer is highly crosstinked with increased wear performance properties over traditional UHMWPE.
This document from Smith & Nephew outlines the application for their Crosslinked Polyethylene Articular Inserts. It does not contain information about the acceptance criteria or a study that proves the device meets those criteria in the context of performance metrics like accuracy, sensitivity, or specificity, which are typical for AI/ML or diagnostic devices.
Instead, this document is a 510(k) premarket notification to the FDA, demonstrating substantial equivalence to previously cleared predicate devices. The "acceptance criteria" here implicitly refer to meeting the FDA's regulatory requirements for substantial equivalence, primarily by showing that the new device has the same intended use, base material, and similar design specifications as existing, legally marketed devices, with enhanced wear performance due to the crosslinking process.
Here's a breakdown based on your request, highlighting what is not applicable (N/A) for this type of submission:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|
| Substantial Equivalence to Predicate Devices: | |
| - Same intended use | - "The intended use... are the same as subject identical components fabricated from conventional non-Crosslinked Ultra High Molecular Weight Polyethylene." (K07107/ page 142) |
| - Same base material | - "...base material... are the same as subject identical components fabricated from conventional non-Crosslinked Ultra High Molecular Weight Polyethylene." (K07107/ page 142) |
| - Same design specifications (overall design and function) | - "The overall design and function of the Crosslinked components have not been changed over that of their identical counterparts manufactured from conventional UHMWPE" (K07107/ page 142, Substantial Equivalence Information) |
| - Enhanced wear performance (due to crosslinking) | - "As a result, the polymer is highly crosslinked with increased wear performance properties over traditional UHMWPE." (K07107/ page 142) |
| - Indications for Use are identical to predicate devices | - "The indications for each device system are identical to the indications for each cleared predicate knee system." (K07107/ page 142 and {4}) |
| Regulatory Classification: | |
| - Complies with 21 CFR 888.3560 (Knee joint patellofemorotibial polymer semi-constrained cemented prosthesis - Class II) | - Device is seeking clearance under this regulation. |
| - Complies with 21 CFR 888.3565 (Knee joint patellofemorotibial polymer semi-constrained uncemented prosthesis - Class II) | - Device is seeking clearance under this regulation. |
2. Sample size used for the test set and the data provenance:
- N/A. This is a 510(k) submission primarily relying on a comparison to predicate devices and the enhanced material properties. It does not describe a clinical performance study with a test set of patient samples in the way an AI/ML or diagnostic device would. The "test" for this device relates to material properties (wear performance) and design equivalence, which are typically evaluated through bench testing and engineering analysis rather than human-data-based test sets.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- N/A. As above, no such "test set" or "ground truth" derived from expert consensus on patient data is mentioned in this submission. The ground truth for material properties would be established through standardized material testing methods.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- N/A. Not applicable for this type of submission.
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:
- N/A. This device is a knee implant component, not an AI-powered diagnostic or assistive tool. MRMC studies are not relevant here.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- N/A. This device is a physical medical implant, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- For the substantial equivalence claim, the "ground truth" is established by the existence and regulatory clearance of the predicate devices. The claim is that the new device meets the same performance and safety standards as these established devices, with the added benefit of improved wear resistance.
- For the improved wear properties, the ground truth would be based on engineering and material science testing standards, comparing the crosslinked polyethylene to conventional UHMWPE. This document states "the polymer is highly crosslinked with increased wear performance properties over traditional UHMWPE," implying such testing was conducted, but details are not provided in this summary.
8. The sample size for the training set:
- N/A. Not applicable. There is no AI/ML model being trained.
9. How the ground truth for the training set was established:
- N/A. Not applicable. There is no AI/ML model being trained.
§ 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.