(90 days)
The Modular Rotating Hinge Knee is intended to be implanted with bone cement for the following conditions:
- There is destruction of the joint surfaces, with or without significant bone deformity.
- The cruciate and/or collateral ligaments do not stabilize the knee joint.
- The ligaments are inadequate and/or the musculature is weak.
- Revision is required of a failed prosthesis where there has been gross instability, with or without bone loss or inadequate soft tissue.
The Modular Rotating Hinge Knee is a tricompartmental knee system. It consists of a stemmed femoral component and a stemmed tibial rotating component connected by a set of bushings and an axle. A bumper locks this assembly. This assembly provides motion through the axle/bushing combination in the flexion/extension plane. The articulation between the cylindrical bearing surfaces on the underside of the tibial rotating component and a tibial insert provide motion in the rotation plane. The tibial insert is assembled to a tibial stemmed tray which incorporates a longitudinal bore to accept a tibial sleeve. The metallic components are manufactured from cast cobalt-chromiummolybdenum alloy (Vitallium® Alloy) conforming to ASTM F-75. The polyethylene components are manufactured from Ultra-High Molecular-Weight Polyethylene (UHMWPE) conforming to standard ASTM F648.
The provided text describes a 510(k) premarket notification for a medical device, the Howmedica Osteonics® Modular Rotating Hinge Knee. This submission primarily focuses on establishing substantial equivalence to previously cleared predicate devices rather than presenting a detailed study proving the device meets specific performance acceptance criteria.
Therefore, many of the requested details regarding acceptance criteria, study design, and performance metrics (especially those related to AI or clinical effectiveness studies) are not applicable or not present in the provided document. The document mainly discusses mechanical and material equivalence.
Here's a breakdown based on the information available:
1. Table of Acceptance Criteria and the Reported Device Performance:
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Material Equivalence: Metallic components from cast cobalt-chromium-molybdenum alloy (Vitallium® Alloy) conforming to ASTM F-75. | Meets: Metallic components are manufactured from cast cobalt-chromium-molybdenum alloy (Vitallium® Alloy) conforming to ASTM F-75. |
| Material Equivalence: Polyethylene components from Ultra-High Molecular-Weight Polyethylene (UHMWPE) conforming to standard ASTM F648. | Meets: Polyethylene components are manufactured from Ultra-High Molecular-Weight Polyethylene (UHMWPE) conforming to standard ASTM F648. |
| Mechanical Performance: Comparable contact and constraint properties to predicate devices (Kinematic Rotating Hinge Knee, Kinemax Plus, and Duracon Total Stabilizer Knee). | Meets: "Mechanical and multi-axis static testing demonstrate the comparable contact and constraint properties of these components." |
| Intended Use Equivalence: Same intended uses as predicate devices. | Meets: The device's intended uses are comparable to those for which predicate devices are cleared. |
| Basic Design Concept Equivalence: Similar basic design concepts as predicate devices. | Meets: The device shares basic design concepts with the predicate devices. |
2. Sample size used for the test set and the data provenance:
- Not explicitly stated. The document mentions "Mechanical and multi-axis static testing," but does not provide details on the sample size of tested implants or components.
- Data Provenance: Not specified, but generally, such testing would be conducted in a laboratory setting by the manufacturer (Howmedica Osteonics Corp.).
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable/Not stated. This type of information is typically relevant for studies involving human interpretation (e.g., medical imaging, clinical diagnosis). For mechanical testing of an orthopedic implant, the "ground truth" is typically defined by engineering specifications and physical measurements, not expert human interpretation.
4. Adjudication method for the test set:
- Not applicable/Not stated. Adjudication methods (like 2+1, 3+1) are used to resolve discrepancies among multiple human readers. For mechanical and material testing, the assessment usually relies on standardized test methods and quantitative measurements.
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. This is a medical device, a knee prosthesis, not an AI-powered diagnostic or assistive technology. Therefore, an MRMC study related to AI assistance for human readers is not relevant.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- No. As above, this is a physical medical implant, not an algorithm.
7. The type of ground truth used:
- The "ground truth" for this submission is based on engineering specifications, material standards (ASTM F-75, ASTM F648), and comparative mechanical testing results against predicate devices.
8. The sample size for the training set:
- Not applicable/Not stated. This refers to a "training set" in the context of machine learning, which is not relevant for this device.
9. How the ground truth for the training set was established:
- Not applicable/Not stated. Again, "training set" and its ground truth establishment are concepts for AI/ML, not for the physical medical device described.
§ 888.3510 Knee joint femorotibial metal/polymer constrained cemented prosthesis.
(a)
Identification. A knee joint femorotibial metal/polymer constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits translation or rotation in one or more planes and has components that are linked together or affined. This generic type of device includes prostheses composed of a ball-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a ball at the head of a column rising from the stemmed tibial component. The ball, the column, the tibial plateau, and the stem for fixation of the tibial component are made of an alloy, such as cobalt-chromium-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the femoral component's flat outer surface. The flat outer surface of the tibial component abuts both a reciprocal flat surface within the cavity of the femoral component and flanges on the femoral component designed to prevent distal displacement. The stem of the femoral component is made of an alloy, such as cobalt-chromium-molybdenum, but the socket of the component is made of ultra-high molecular weight polyethylene. The femoral component has metallic runners which align with the ultra-high molecular weight polyethylene tracks that press-fit into the metallic tibial component. The generic class also includes devices whose upper and lower components are linked with a solid bolt passing through a journal bearing of greater radius, permitting some rotation in the transverse plane, a minimal arc of abduction/adduction. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.