(81 days)
The Implex CKS Hedrocel Revision Femoral Spacers are indicated in the revision or salvage of failed previously reconstructed knee procedures and implants; particularly in situations where bone loss has occurred from removal of prior implantations, infection or trauma. This device is intended for cemented use only.
The use of the Continuum Knee System Hedrocel Revision Femoral Spacers are indicated for:
- For cemented use only.
- Total Knee Replacement (TKR) in severely disabled joints as a result of degenerative arthritis;
- Secondary revision of a previously unsuccessful revision femoral component;
- Other knee problems where clinical experience has shown that alternative modes of treatment are less likely to achieve satisfactory results;
- Trauma, or other fractures in which adequate bony fixation cannot be obtained;
- Non-union of the proximal tibia; and
- Salvage of a failed primary or secondary total knee or uni-knee arthroplasty.
The CKS Hedrocel Distal Femoral Spacers will have 4 thickness options of 4, 8, 12, and 16 mm. The distal femoral spacers will be available in both full and chamfered spacer options. The CKS Hedrocel Posterior Femoral Spacers will be available in 3 thickness options of 4, 8, and 12 mm. The CKS Hedrocel Spacers are comprised of Hedrocel porous tantalum and are to be fastened to Implex Continuum Knee System Revision Femoral Components using the same Instrumentation and fastener bolts.
This document is a 510(k) Pre-market Notification for the Implex Continuum Knee System Hedrocel Revision Femoral Spacers. It seeks to establish substantial equivalence to previously marketed devices. The document does not describe an acceptance criteria and study that proves the device meets specific performance metrics in the way modern device submissions or AI/software validation studies would.
Instead, the "acceptance criteria" here is the regulatory standard of "substantial equivalence" to predicate devices already on the market. The "study" proving this is a comparison to existing predicate devices and a reliance on their previously accepted performance data.
Here’s a breakdown based on your request, highlighting what is present and what is absent in this type of regulatory submission:
Description of Acceptance Criteria and Study to Prove Device Meets Criteria
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Regulatory Standard) | Reported Device Performance (Basis for Equivalence) |
|---|---|
| Substantial Equivalence: The device is as safe and effective as a legally marketed predicate device. This is primarily evaluated by comparing: | The Implex CKS Hedrocel Revision Femoral Spacers are compared to: |
- Implex CKS Revision Femoral Spacers (original)
- Implex Continuum Porous Patella
- Implex Hedrocel Acetabular Restrictor
The claim of substantial equivalence is based on the device having:
- Similar intended use: Revision/salvage of failed knee procedures, cemented use.
- Similar technological characteristics: Comprised of Hedrocel porous tantalum.
- Reliance on previous testing of predicate devices and their materials. |
| * Intended Use | * The intended use for the new device is consistent with the predicate devices: Total Knee Replacement (TKR) in severely disabled joints, secondary revision, trauma, non-union, salvage of failed arthroplasty (for cemented use only). |
| * Technological Characteristics (e.g., material, design principles) | * The device is comprised of Hedrocel porous tantalum, similar to components in the predicate devices. Design features (thickness options, full/chamfered) are described. |
| * Performance Data (to demonstrate safety and effectiveness for its intended use, typically through non-clinical bench testing or clinical studies for new technology) | * The submission states: "Previous testing of the predicate devices and their respective materials are sufficient for substantial equivalence determination. The relevant data is found in Master File MAF #920 and K962468." This indicates a reliance on prior mechanical/material testing data associated with the predicate devices and the Hedrocel material, rather than new device-specific performance data in this submission. |
2. Sample size used for the test set and the data provenance
- Sample Size for Test Set: Not applicable in the context of a 510(k) submission relying on predicate device data for mechanical performance. There isn't a "test set" of patient data or new device performance data described in this summary. The "test" is the comparison process itself to the predicates.
- Data Provenance: The provenance for the underlying material and predicate device testing (MAF #920 and K962468) is not detailed in this summary. These would typically involve bench testing (e.g., fatigue, wear, strength) of materials and components, which is laboratory-based and not patient-data driven.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not applicable. This submission is for a medical implant (revision femoral spacers for knee replacement). "Ground truth" in this context would generally refer to a definitive diagnosis or outcome for a patient, which is not being established or used as a "test set" here. The assessment is regulatory by the FDA based on the provided technical comparison.
4. Adjudication method for the test set
- Not applicable. There is no "test set" in the sense of clinical cases requiring adjudication. The FDA (specifically the Division of General and Restorative Devices, Office of Device Evaluation) reviewed the submission to determine substantial equivalence.
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
- Not applicable. This is not an AI/software device. It's a medical implant.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable. This is not an AI/software device.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- Not applicable in the human data sense. The "ground truth" for the material and mechanical properties of the Hedrocel technology and the predicate devices would have been established through a combination of:
- Engineering specifications and standards: Defining required material properties and mechanical performance.
- Bench testing: Laboratory measurements of strength, fatigue, wear, etc.
- Histopathology/biological studies: For biocompatibility and osseo-integration (though not explicitly mentioned as "ground truth" here, it's relevant for porous materials).
- Clinical experience/outcomes data: For the predicate devices, showing they were safe and effective when previously marketed (though not specified as a "test set" for this submission).
8. The sample size for the training set
- Not applicable. This is not an AI/software device. There is no "training set."
9. How the ground truth for the training set was established
- Not applicable. This is not an AI/software device.
In summary: This 510(k) submission is a regulatory pathway for orthopedic implants based on demonstrating similarity to previously cleared devices. It relies heavily on the safety and effectiveness already established for the predicate devices and the material technology (Hedrocel). It does not involve a "study" in the sense of a clinical trial or a performance validation for a novel AI/software product.
§ 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.