(149 days)
The Apex Knee™ System is intended for use as a primary or revision total knee replacement. This prosthesis may be used for the following conditions, as appropriate:
• Non-inflammatory degenerative joint disease, including osteoarthritis and avascular necrosis;
Rheumatoid arthritis; Correction of functional deformity; Revision procedures where other treatments or devices have failed;
The porous coated femoral component may be used cemented or uncemented (biological fixation). The porous coated tibial baseplate component may be used uncemented (biological fixation). All other femoral, tibial baseplate and patellar components are indicated for cemented use only.
The Apex Knee™ Modular Tibial Augments are intended to be bolted to the Tibia Baseplate and cemented to the prepared tibia. The Apex Revision Knee system augments are intended to be bolted to the femoral component and cemented to the prepared femur.
The proposed devices are intended to be used for primary and revision total knee replacement.
The Revision Tibia Baseplates offer enhanced torsional stability by adding keels to the posterior end of the device. This design is similar to keeled stem designs currently marketed.
The retaining bolt modifications offer additional bolt sizes that allow the cleared tibial inserts to lock into the proposed longer Revision tibial Baseplate.
The material of the proposed Revision Tibial Baseplate is Cobalt Chrome, CoCr (ASTM F75). The material if the proposed retaining bolts is Ti-6Al-4V E.L.I (ASTM F136)
This document describes the regulatory submission for the Apex Revision Knee System (K163332), a medical device. The information provided heavily emphasizes substantial equivalence to a predicate device (K153437) rather than providing detailed acceptance criteria and a study demonstrating the device meets those criteria in a traditional sense (e.g., performance metrics, statistical analysis).
Here's a breakdown of the requested information based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The submission does not provide specific acceptance criteria in the form of performance metrics (e.g., accuracy, sensitivity, specificity) or a study with reported performance values. Instead, the basis for approval is "substantial equivalence" to a predicate device.
The study presented is a justification of substantial equivalence, not a performance study against specific acceptance criteria. The "reported device performance" is essentially that it is considered "as safe, as effective, and performs as well as or better than the legally marketed predicate."
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not applicable in the traditional sense of a clinical or performance study with a test set of data. The "test set" here refers to the new proposed components and their interaction with existing components.
- Data Provenance: Not applicable. The "study" is a series of justifications and evaluations rather than a data-driven test.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of those Experts
- Number of Experts: Not mentioned.
- Qualifications of Experts: Not mentioned.
4. Adjudication Method for the Test Set
- Adjudication Method: Not mentioned, as this was not a study involving human interpretation or subjective assessment.
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
- MRMC Study: No. This device is a mechanical knee prosthesis, not an AI-assisted diagnostic tool.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) Was Done
- Standalone Performance: No. This device is a physical implant.
7. The Type of Ground Truth Used
The "ground truth" here is the established safety and effectiveness of the legally marketed predicate device (K153437). The new device is deemed equivalent because its modifications do not introduce new risks. The justifications listed are:
- "KTR-116 Tray Fatigue FEA" (Finite Element Analysis) - This indicates an engineering simulation was performed for fatigue, but the results or a direct comparison to acceptance criteria are not provided in this summary.
8. The Sample Size for the Training Set
- Sample Size: Not applicable. This is not a machine learning model.
9. How the Ground Truth for the Training Set Was Established
- Ground Truth Establishment: Not applicable.
Summary of Device Acceptance and Study:
The acceptance of the Apex Revision Knee System (K163332) is based on the demonstration of substantial equivalence to a previously cleared predicate device (K153437). The "study" is less of a traditional performance study and more of a technical justification.
Acceptance Criteria (Implied by Substantial Equivalence):
| Acceptance Criteria (Implied) | Reported Device "Performance" (Justification) |
|---|---|
| Safety and Effectiveness equivalent to predicate device. | "The proposed devices with modifications are substantially equivalent to the existing Apex Revision Knee System cleared in K153437 as the basic design, interface, fundamental technology, materials and intended use are the same." |
| "The use of the new Revision Knee System components with the existing revision knee components do not introduce any new risks of safety or efficacy." | |
| "Testing was not conducted but the devices were evaluated and no-testing justifications were written... The modifications do not raise any new safety or effectiveness concerns." | |
| "The conclusions drawn from the nonclinical tests demonstrate that the devices are as safe, as effective, and performs as well as or better than the legally marketed [predicate]." | |
| Material compatibility. | "The material of the proposed Revision Tibial Baseplate is Cobalt Chrome, CoCr (ASTM F75). The material if the proposed retaining bolts is Ti-6Al-4V E.L.I (ASTM F136)" - Implied acceptance based on the use of standard, known biocompatible materials. |
| Structural integrity (e.g., fatigue resistance) for additions. | "KTR-116 Tray Fatigue FEA" - (Finite Element Analysis for fatigue was performed, implying it met internal requirements, though specific results/criteria are not detailed in this summary). |
Key takeaways from the document regarding the "study":
- This was a Special 510(k) submission, used when modifications to a legally marketed device do not significantly alter its safety or effectiveness.
- The manufacturer explicitly states that "Testing was not conducted" in a hands-on sense for comparing the new device against the predicate. Instead, "justifications were written" and the devices were "evaluated."
- The primary justification is that the modifications (additional baseplate and retaining bolt types) maintain the "basic design, interface, fundamental technology, materials and intended use" of the cleared predicate device.
- The listed "study" is "KTR-116 Tray Fatigue FEA", which is a Finite Element Analysis for fatigue. This is a computational simulation, not a physical study with a test set of real-world data or human subjects. The details of the FEA results or acceptance criteria for fatigue are not included in this summary document.
- The "ground truth" for demonstrating equivalence is the established safety and effectiveness profile of the predicate device (K153437).
§ 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.