(81 days)
The DePuy Sigma CR-F femoral component is intended for cemented use only. Candidates for total knee replacement include patients with a severely painful and/or severely disabled joint resulting from osteoarthritis, post-traumatic arthritis, rheumatoid arthritis, or a failed previous implant.
The Sigma CR-F femoral component is part of the PFC Sigma Total Knee Replacement System. It is a Co-Cr-Mo femoral component with an asymmetric trochlear groove, available in sizes 1.5 - 6, in right and left versions. The fixation surface is textured. It incorporates two pegs to provide additional stability and recessed cement pockets for enhanced cement fixation. These features have not changed from those on the predicate PFC Sigma CR femoral component.
Here's an analysis of the provided text regarding the DePuy Sigma CR-F femoral component, focusing on the acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Substantial Equivalence to Predicate Device (PFC Sigma CR femoral component) | Demonstrated through: |
- Same indications, materials, manufacturing process, sterilization, and packaging.
- Non-clinical testing: Comparisons of tibiofemoral contact area and pressure, range of motion analysis, and constraint testing showed equivalence. |
2. Sample Size Used for the Test Set and Data Provenance:
- Test Set Sample Size: Not applicable. The submission explicitly states "Clinical testing was not necessary to determine substantial equivalence between the subject Sigma CR-F femoral components and the predicate devices."
- Data Provenance: Not applicable, as no clinical testing was performed. Non-clinical testing data (e.g., biomechanical testing) would typically be generated in a lab setting, likely in the country of manufacture (USA, given the applicant is DePuy Orthopaedics Inc. in Warsaw, Indiana). The nature of the non-clinical tests suggests a prospective approach to data generation.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:
- Not applicable, as no clinical testing with a "test set" and "ground truth" was conducted in the human-in-the-loop sense. The ground truth for non-clinical testing is typically defined by engineering specifications, biomechanical principles, and established testing standards.
4. Adjudication Method for the Test Set:
- Not applicable, as no clinical human-reader-based test set was used.
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:
- No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This device is a physical knee implant, not an AI software/device that would assist human readers in interpretation.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Not applicable in the context of AI algorithms. However, "standalone" in a broader sense refers to the device's inherent mechanical performance. The non-clinical testing (tibiofemoral contact area, pressure, range of motion, constraint testing) demonstrates the standalone performance of the implant itself, comparing it to the predicate device.
7. The Type of Ground Truth Used:
- The "ground truth" for demonstrating substantial equivalence was based on engineering and biomechanical performance metrics established for the predicate device. These include:
- Material specifications
- Manufacturing processes
- Sterilization methods
- Packaging
- Biomechanical properties: tibiofemoral contact area and pressure, range of motion, and constraint characteristics.
The ground truth here is derived from the established and proven performance of the predicate device, not clinical outcomes or pathology from a patient population related to the new device itself.
8. The Sample Size for the Training Set:
- Not applicable. This is not an AI device that requires a training set of data.
9. How the Ground Truth for the Training Set was Established:
- Not applicable, as there is no "training set" for this type of medical device submission.
§ 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.