(101 days)
Joint replacement is indicated for patients suffering from disability due to: degenerative, post-traumatic or rheumatoid arthritis; avascular necrosis of the femoral condyle; post-traumatic loss of joint configuration, particularly when there is patellofemoral erosion, dysfunction or prior patellectomy; moderate valgus, varus or flexion deformities; treatment of fractures that are unmanageable using other techniques. This device may also be indicated in the salvage of previously failed surgical attempts. All devices are intended for cemented applications except for the 3DKNEET™ Porous Coated Femur which is intended for cementless applications. While knee replacements are not intended to withstand activity levels and loads of normal healthy bone, they are a means of restoring mobility and reducing pain for many patients.
The EMPOWR PS Knee System is a line extension to the current EMPOWR system (previously cleared as Rebel 3DKNEE System). It is a total knee system that includes non-porous distal femoral implants made from cast CoCr alloy per ASTM F75 and tibial insert implants made from Highly Cross-Linked with Vitamin E (HXL VE) UHMWPE.
The provided text is an FDA 510(k) summary for a medical device called the EMPOWR PS Knee System. It describes the device, its indications for use, and its substantial equivalence to predicate devices. However, this document does not contain information about acceptance criteria or a study proving that the device meets those criteria, as typically found for AI/ML-driven medical devices. This knee system is a traditional orthopedic implant, and its clearance relies on non-clinical testing for mechanical properties and substantial equivalence to existing devices, not on performance metrics like sensitivity, specificity, or reader studies.
Therefore, most of the requested information cannot be extracted from this document. I can, however, provide what is available.
Here's a breakdown based on the provided text, noting where information is absent:
1. Table of Acceptance Criteria and Reported Device Performance
This document does not specify quantitative acceptance criteria or performance metrics (like accuracy, sensitivity, specificity) because it's for a physical knee implant cleared through the 510(k) pathway, focusing on mechanical properties and substantial equivalence rather than diagnostic or prognostic performance. The "performance" assessment is based on non-clinical testing.
| Acceptance Criteria (Not explicitly stated as numeric) | Reported Device Performance |
|---|---|
| Mechanical strength/durability | "FEA assessments for PS femur condyle closing loads, PS femur flange closing loads, and PS femur wedge loading. CAD analysis was completed for range of motion, and testing was completed for post fatigue, contact area, constraint, and lateral subluxation." |
| Substantial Equivalence to predicate devices | "All testing has determined that the device is substantially equivalent to the predicate devices." (Implies that the non-clinical tests results met engineering standards and were comparable to the predicate devices, though specific thresholds or comparative values are not provided in this summary.) "This device is comparable to the predicate devices in indications, material, dimensions, surgical implantation technique, and intended use. This device has the same implant packaging and sterilization as the EMPOWR Knee are no different technological characteristics from the predicate device." |
2. Sample Size Used for the Test Set and Data Provenance
This information is not applicable and not provided. The testing described is non-clinical (FEA, CAD analysis, fatigue testing of components), not involving human patient data or a "test set" in the context of an AI/ML device.
3. Number of Experts Used to Establish Ground Truth and Qualifications
This information is not applicable and not provided. The "ground truth" for a knee implant's mechanical performance is typically established through engineering standards, material science, and biomechanical principles, not through expert clinical consensus on a dataset.
4. Adjudication Method
This information is not applicable and not provided. Adjudication methods like 2+1 or 3+1 are used for establishing ground truth in clinical data for diagnostic/prognostic studies, which is not what this document describes.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No. An MRMC study was not done. Such studies are relevant for diagnostic devices that assist human readers (e.g., radiologists interpreting images). This device is a physical knee implant.
6. Standalone Performance Study
Yes, in a sense, a standalone (algorithm-only, or device-only) evaluation was performed regarding its mechanical properties. The "Non-Clinical Testing" section describes evaluations of the device's components and design:
- FEA assessments for PS femur condyle closing loads, PS femur flange closing loads, and PS femur wedge loading.
- CAD analysis for range of motion.
- Testing for post fatigue, contact area, constraint, and lateral subluxation.
These tests evaluate the device itself without human-in-the-loop performance.
7. Type of Ground Truth Used
The ground truth for the non-clinical testing appears to be based on:
- Engineering standards: Implied by the type of mechanical tests (e.g., fatigue, loading) and material specifications (ASTM F75 for CoCr alloy).
- Biomechanics: Underlying principles for range of motion, constraint, and subluxation.
- Comparison to predicate devices: The concept of "substantial equivalence" means the device's performance aligns with that of already-marketed, safe, and effective predicate devices.
8. Sample Size for the Training Set
This information is not applicable and not provided. "Training set" is a term used for AI/ML development. For a physical device, development involves design, prototyping, and iterative engineering, not a training set of data.
9. How Ground Truth for the Training Set Was Established
This information is not applicable and not provided for the reasons stated above.
§ 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.