(56 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 (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 posterior stabilized system offers a femoral component and two tibial inserts (PS (K102578) and PS-C (subject device)) offering different levels of constraint. The PS-C Insert post is approximately 1 mm larger than the PS Insert (K102578). The slightly larger post is designed to produce more varus/valgus and internal/external rotational constraint.
The provided text describes a 510(k) summary for the Apex PS Knee System PS-C Insert and its comparison to a predicate device, the Apex PS Knee System, PS Insert (K102578). The document focuses on demonstrating substantial equivalence through non-clinical testing rather than clinical studies using patient data. Therefore, many of the requested categories related to clinical study design, such as sample size, expert ground truth, and reader studies, are not applicable in this context.
Here's a breakdown of the available information:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly met by demonstrating that the subject device's performance characteristics are either identical to or within acceptable variations of the predicate device, as determined by specific ASTM standards. No explicit numerical "acceptance criteria" are stated for performance metrics in the table; rather, the subject device's design and mechanical properties are compared to the predicate.
| Characteristic | Predicate Device (Apex PS Knee System, PS Insert - K102578) | Subject Device (Apex PS Knee System PS-C Insert) | Comparison / Performance |
|---|---|---|---|
| Intended Use | Primary and revision total knee replacement | Yes | Identical intended use. |
| Design: Post Width | 15 - 20 mm depending on size | 16 - 21 mm depending on size | Slightly larger post (approx. 1mm larger) in the subject device, designed to produce more varus/valgus and internal/external rotational constraint. |
| Design: Varus/Valgus Constraint | No Varus/Valgus Constraint | 3 - 4° | Subject device shows added varus/valgus constraint compared to the predicate, as designed. |
| Design: Internal/External Rotation | 14 - 20° | 11 - 17° | Subject device shows a narrower range of internal/external rotation compared to the predicate, indicating increased rotational constraint, as designed. |
| Design: Range of Motion | 6° hyperextension and 132° flexion | Identical to K102578 | Identical. |
| Design: Condyle Geometry and Contact Area | Toroidal convex femoral surface and a toroidal concave insert surface with medial-lateral and anterior-posterior radii that increase with component size | Identical geometry to K102578 | Identical. |
| Design: Tibia Baseplate Mating Feature | Mates with two parallel dovetail rails on Tibia Baseplate. | Identical to K102578 | Identical. |
| Materials | UHMWPE ASTM F648 | Identical to K102578 | Identical Ultra high molecular weight polyethylene (UHMWPE ASTM F648). |
| Packaging & Sterilization | Ethylene oxide, SAL 10^-6^, Paper Board Box, Double Tyvek inner pouch | Identical to K102578 | Identical. |
| Non-Clinical Test Summary | ROM evaluation per ASTM F2083-08, FDA "Class II Special Controls Guidance Document: Knee Joint Patellofemorotibial and Femorotibial Metal/Polymer Porous-Coated Uncemented Prostheses; Guidance for Industry and FDA" Tibio-Femoral Constraint per ASTM F2083-08, ASTM F1223-03 | N/A (Tests conducted on subject device) | The tests were conducted to demonstrate the subject device's performance against the established standards (ASTM F2083-08, ASTM F1223-03) and FDA guidance, allowing for comparison of its characteristics (like varus/valgus and rotational constraint) against the predicate. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not specified in terms of number of devices or units tested. The document refers to "the following tests were conducted," implying a sufficient number of samples were used for the mechanical tests to be representative and meet the requirements of the ASTM standards.
- Data Provenance: Not applicable as no clinical data (patient data) was used. The tests were non-clinical, likely bench testing performed by the manufacturer or a contract lab.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- Not Applicable: No clinical studies were performed, and thus no "ground truth" based on expert medical evaluation of patient data was established for a test set. The "ground truth" for non-clinical testing refers to the accepted standards (ASTM F2083-08, ASTM F1223-03) and FDA guidance.
4. Adjudication Method for the Test Set
- Not Applicable: No human review or adjudication of clinical outcomes was involved.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
- No: No MRMC study was performed. The evaluation was based on non-clinical, mechanical testing.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- Not Applicable: This device is a mechanical implant, not an algorithm or AI system.
7. The Type of Ground Truth Used
- Standards and Guidance: The "ground truth" or reference for performance was established by recognized industry standards (ASTM F2083-08, ASTM F1223-03) and FDA guidance documents specific to knee joint prostheses. These standards define the methods and expected performance characteristics for evaluating such devices.
8. The Sample Size for the Training Set
- Not Applicable: No training set was used as this involved mechanical testing of a physical device, not an AI or algorithm.
9. How the Ground Truth for the Training Set Was Established
- Not Applicable: No training set was used.
§ 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.