(71 days)
The Kinematio® All-Polyethylene Patella with Three Pegs is intended to be used with the femoral and tibial components of the Kinematic® and Kinematic® II total knee systems, and the distal femoral component of the Howmedica Modular Replacement System in primary and/or revision total knee arthroplasty. This component is intended to resurface the articular surface of the patella. It is intended to be implanted with bone cement.
The Kinematic® All-Polyethylene Patella with Three Pegs is available in three sizes: small, medium, and large. This component has a rounded, dome articular surface that is intended to mate with the intercondylar recess of the above-referenced femoral components. The articular surface of the subject device is identical to the articular surface of the previously cleared Kinematio® Patella.
The undersurface design of the Kinematic® All Polyethylene Patella with Three Pegs has a triangular cement recess with three straight pegs. This undersurface design is identical to the Duracon® All Polyethylene Patella II undersurface. The existing Kinematio® Patella has a central keel with fixation holes. This undersurface is being modified to three pegs to allow common instrumentation to be used throughout Howmedica's total knee systems.
The Kinematic® All-Polyethylene Patella with Three Pegs is fabricated from Ultra-High Molecular Weight Polyethylene, which conforms to ASTM specification F-648. The Kinematio® All Polyethylene Patella with Three Pegs will be made available in two versions: one will be sterilized via a room air gamma sterilization method, and the second version will be sterilized via a gamma sterilization method in an inert environment followed by heat treatment.
The provided text describes a 510(k) premarket notification for a medical device, the Kinematic® All-Polyethylene Patella with Three Pegs. This submission aims to demonstrate "substantial equivalence" to legally marketed predicate devices, rather than establishing specific acceptance criteria and proving performance through a clinical study with detailed metrics typically found for AI/ML devices or novel technologies.
Therefore, many of the requested sections regarding acceptance criteria, sample sizes, ground truth establishment, expert adjudication, and comparative effectiveness studies are not applicable to this type of regulatory submission (a 510(k) for a class II medical device like a knee implant from 1997). The focus is on demonstrating equivalence based on design, materials, intended use, and operational principles.
However, I can extract information related to the device description and the limited performance data presented to support the substantial equivalence claim.
Kinematic® All-Polyethylene Patella with Three Pegs Device Performance Summary
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Mechanical/Biomechanical Equivalence: |
- Similar design features
- Similar materials
- Similar operational principles | Design/Material Equivalence:
- Articular surface identical to Kinematic® Patella.
- Undersurface design (triangular cement recess with three pegs) identical to Duracon® All Polyethylene Patella II undersurface.
- Fabricated from Ultra-High Molecular Weight Polyethylene (conforms to ASTM F-648).
Functional Equivalence (Limited Testing): - Patello-femoral contact area testing presented.
- Lateral subluxation testing of the patella presented.
Intended Use Equivalence: - Intended for use with Kinematic® and Kinematic® II total knee systems, and Howmedica Modular Replacement System.
- Intended to resurface the articular surface of the patella.
- Intended to be implanted with bone cement. |
2. Sample size used for the test set and the data provenance
- Sample Size: Not explicitly stated. The text mentions "Patello-femoral contact area and lateral subluxation testing of the patella were presented," implying some form of mechanical or in-vitro testing. However, no number of samples (e.g., number of implants tested, or number of cadaveric knees used) is provided.
- Data Provenance: Not specified. Given the nature of a 510(k) for an orthopedic implant, these tests would typically be laboratory-based (in-vitro) mechanical or biomechanical tests. There is no mention of human clinical data or geographical origin.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not Applicable. This type of information is pertinent to studies involving human data and expert judgment, such as image interpretation. For a device like a knee implant, performance is assessed through engineering specifications, material properties, and biomechanical testing, not typically through expert consensus on a "ground truth" test set in the same way an AI algorithm for diagnosis would be.
4. Adjudication method for the test set
- Not Applicable. See point 3.
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/ML device. The submission is for a physical 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/ML device.
7. The type of ground truth used
- The "ground truth" in this context would be defined by engineering specifications, biomechanical standards, and material properties (e.g., ASTM F-648 for UHMWPE). The testing for patello-femoral contact area and lateral subluxation would be compared against expected values or performance of the predicate devices. There is no "expert consensus" or "pathology" in the typical sense for this device.
8. The sample size for the training set
- Not Applicable. This is not an AI/ML device and thus does not have a "training set."
9. How the ground truth for the training set was established
- Not Applicable. See point 8.
§ 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.