(267 days)
The Genesis II XLPE Resurfacing Patellar Components are intended to be used with Smith & Nephew Total Knee Systems and Patello-Femoral Replacement Knee Systems and their cleared Indications for Use.
Indications for Total Knee Replacement
- Rheumatoid arthritis.
- Post-traumatic arthritis, osteoarthritis, or degenerative arthritis.
- Failed osteotomies, 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.
- 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 and/or lateral collateral ligament) are absent or incompetent.
Indications for Patello-Femoral Replacement
- Degenerative arthritis in the distal femur and patella;
- A history of patellar dislocation or patellar fracture; and
- Failed previous surgery (arthroplasty, tibial tubercle elevation, lateral release) where pain, deformity or dysfunction persists.
The Smith & Nephew Patello-Femoral Implants are intended for implantation with bone cement.
Subject of this Premarket Notification are the Genesis II XLPE resurfacing patellar components manufactured from highly cross linked polyethylene (XLPE) material. The Genesis II XLPE resurfacing patellar components are intended to be used with the following knee systems
- Smith & Nephew Total Knee Systems
- Smith & Nephew Patello-Femoral Knee Systems
- Competitor PFJ Patella-Femoral Knee Implants K051086
- Legion Hinge Knee System K081111
- Genesis II Constrained System K962137
Components of this premarket notification include
- Round and Oval Patellar components manufactured from highly cross-linked polyethylene (7.5 Mrad XLPE) material.
This document is a 510(k) Premarket Notification for the Genesis II XLPE Resurfacing Patellar Components. It is a regulatory submission to the FDA, demonstrating substantial equivalence to previously cleared devices. It describes mechanical testing performed to support a material change, not a study proving a device meets specific clinical acceptance criteria or a comparative effectiveness study.
Therefore, many of the requested sections in your prompt (e.g., sample size for test/training set, number of experts, adjudication methods, MRMC study, standalone performance, type of ground truth) are not applicable or not explicitly detailed in this type of regulatory submission. The document focuses on showing mechanical equivalency rather than clinical performance.
However, I can extract information related to the acceptance criteria for the mechanical testing and the reported performance from the document.
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state numerical acceptance criteria for the mechanical tests (Static Shear and Fatigue Shear Testing). Instead, it states that the tests were conducted "to further support a determination of substantial equivalence" and that "Test results demonstrated that the proposed devices are substantially equivalent to the previously cleared predicate device." This implies that the acceptance criterion was the demonstration of performance comparable to the predicate device, although the specific thresholds for "comparable" are not provided.
| Acceptance Criteria Category | Specific Acceptance Criteria (as implied) | Reported Device Performance |
|---|---|---|
| Mechanical Performance | Performance comparable to the previously cleared predicate device for material properties. | "Test results demonstrated that the proposed devices are substantially equivalent to the previously cleared predicate device." (for both Static Shear and Fatigue Shear Testing) |
| Material Change | Highly cross-linked polyethylene (XLPE) material properties are equivalent to the material in reference predicate K071071. | The change in material to highly cross-linked polyethylene is "identical to the material in reference predicate K071071." |
2. Sample size used for the test set and the data provenance
- Sample Size: Not specified in the document.
- Data Provenance: Not explicitly stated, but these would be bench (mechanical) tests performed in a laboratory setting, likely by Smith & Nephew or a contracted testing facility. This is not clinical data (retrospective or prospective from a country of origin).
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not Applicable. Ground truth in this context would refer to clinical or diagnostic accuracy, which is not evaluated here. The "truth" for mechanical testing is derived from engineering principles and standards, not expert clinical consensus.
4. Adjudication method for the test set
- Not Applicable. This is not a clinical study involving human assessment that would require adjudication. Mechanical tests have objective outputs that are compared against predefined engineering specifications or predicate device performance.
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
- No. This is a submission for a medical implant (knee replacement components), not an AI diagnostic device. Therefore, no MRMC comparative effectiveness study was performed or is relevant.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- No. This is not a software algorithm; it is a physical medical device.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- Not Applicable / Engineering Standards. For mechanical testing, the "ground truth" would be established by industry-accepted mechanical testing standards (e.g., ISO, ASTM) and comparison to the known performance characteristics of the predicate device, rather than clinical ground truth like pathology or expert consensus.
8. The sample size for the training set
- Not Applicable. This is not a machine learning or AI device that requires a training set.
9. How the ground truth for the training set was established
- Not Applicable. (See #8)
§ 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.