(71 days)
The P.F.C. Sigma Knee System is indicated for use only with bone cement (PMMA) for patients suffering from severe pain and disability due to permanent structural damage resulting from rheumatoid arthritis, osteoarthritis, post-traumatic arthritis, collagen disorders or pseudogout. This damage may also be the result of trauma or failed prior surgical intervention.
The P.F.C. Sigma Inset Patella is a patellar prosthesis intended for use in Total Knee Replacement. The device is constructed of UHMWPE.
The provided documents are a 510(k) premarket notification for a medical device, the P.F.C. Sigma Knee System Inset Patella. This type of submission focuses on demonstrating substantial equivalence to a legally marketed predicate device, rather than providing new clinical study data with acceptance criteria and performance metrics in the way new drug or novel medical device approvals often do.
Therefore, the documents do not contain information regarding a study that proves the device meets specific acceptance criteria in terms of clinical performance or effectiveness, nor do they include details like sample sizes, expert ground truth establishment, or multi-reader multi-case studies as requested in your prompt.
Instead, the "acceptance criteria" here are that the device is substantially equivalent to a predicate device already on the market, meaning it has the same intended use and similar technological characteristics. The "study" is the comparison made in the 510(k) submission itself.
Here's a breakdown of the requested information based on the provided text, highlighting what is not applicable or not present in a 510(k) submission of this nature:
Acceptance Criteria and Study for P.F.C. Sigma Knee System Inset Patella
This submission is a 510(k) premarket notification, which seeks to establish "substantial equivalence" of a new device to a legally marketed predicate device. As such, it does not typically involve clinical trials or studies with performance-based acceptance criteria as would be seen for novel devices or drugs. The "acceptance criteria" discussed below refer to the criteria for demonstrating substantial equivalence.
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (for Substantial Equivalence) | Reported Device Performance (vs. Predicate) |
|---|---|
| Intended Use: Device has the same intended use as legally marketed predicate device. | Matches: Indicated for use only with bone cement (PMMA) for patients suffering from severe pain and disability due to permanent structural damage resulting from rheumatoid arthritis, osteoarthritis, post-traumatic arthritis, collagen disorders or pseudogout, or trauma/failed prior surgical intervention. This intended use is identical to the P.F.C.® Σ Oval Dome Patella and Universal Inset Patella. |
| Technological Characteristics: Device has similar technological characteristics to legally marketed predicate device. | Similar: |
| - Bone Removal Method | - P.F.C. Σ Inset Patella: reamed cavity (Matches Universal Inset Patella, differs from P.F.C. Σ Oval-Dome Patella's planar resection) |
| - Bone Periphery @ Major Diameter | - P.F.C. Σ Inset Patella: yes (Matches Universal Inset Patella, differs from P.F.C. Σ Oval-Dome Patella's no) |
| - Articulating Surface | - P.F.C. Σ Inset Patella: 1" spherical radius (Matches P.F.C. Σ Oval-Dome Patella, approximately matches the PFC® C/R Femur Patellar Groove 2 which has a 0.8" spherical radius; stated to "Exactly match the PFC® Σ Femur (C/R, C/S & TC3) Patellar Grooves 1") |
| - Cement Pocket Geometry | - P.F.C. Σ Inset Patella: Dovetail Undercut (Matches both predicate devices) |
| - Peg Geometry(ies) | - P.F.C. Σ Inset Patella: Round & Clover (Differs from both predicate devices' Round only; potential area of difference that needs to be justified as not raising new safety/effectiveness concerns). |
| - Material | - P.F.C. Σ Inset Patella: UHMWPE (Matches both predicate devices) |
| Safety and Effectiveness: Does not raise different questions of safety and effectiveness from the predicate device. | Affirmed by FDA determination: The FDA reviewed the 510(k) and determined the device is substantially equivalent for the stated indications for use, noting specific limitations regarding cemented-use only and investigational use for non-cemented fixation. This implies that the differences in technological characteristics (e.g., bone removal, bone periphery, peg geometry) were deemed not to raise new questions of safety or effectiveness. The FDA's letter explicitly states the device is "substantially equivalent." |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Not Applicable / Not Provided: As this is a 510(k) submission, there isn't a "test set" in the context of a clinical study aimed at proving device performance against efficacy endpoints. The "testing" primarily involves
design comparisons and potentially bench testing (though not detailed here) to ensure equivalence. This documentation does not refer to clinical data from a sample size of patients.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
- Not Applicable / Not Provided: Ground truth establishment by experts for a test set is relevant for studies measuring diagnostic accuracy or clinical outcomes. A 510(k) submission typically relies on internal engineering and design expertise to compare the new device to the predicate, and FDA reviewers (qualified medical device experts) evaluate this comparison.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not Applicable / Not Provided: Adjudication methods are used in clinical trials to resolve discrepancies in data interpretation, often by expert panels. This is not part of a 510(k) submission focused on 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 / Not Provided: MRMC studies are specific to diagnostic devices (often imaging AI). This device is an orthopedic implant, and the submission does not involve AI assistance or diagnostic interpretation.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not Applicable / Not Provided: This device is a passive orthopedic implant, not an algorithm or AI system.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- Not Applicable / Not Provided: The "ground truth" for a 510(k) lies in the established safety and effectiveness profile of the predicate device. The new device aims to match or be acceptably similar to this established profile through design and material comparisons, rather than generating new outcomes data for "ground truth."
8. The sample size for the training set
- Not Applicable / Not Provided: There is no "training set" as this is not an AI/machine learning device. The design and manufacturing process would involve internal testing and validation, but not in the context of a "training set" for an algorithm.
9. How the ground truth for the training set was established
- Not Applicable / Not Provided: No training set, therefore no associated ground truth establishment.
§ 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.