(23 days)
The UC-PLUS Solution Unicondylar Knee is intended for use in uni-compartmental degenerative arthritis, local osteonecrosis of the femoral condyle, light to medium uni-compartmental destruction of the knee joint due to idiopathic and posttraumatic degenerative arthritis, traumatic uni-compartmental bone and/or cartilage lesions. It is intended for use with bone cement only.
This knee system consists of a femoral component. The femoral component is fabricated from cast CoCrMo alloy (ASTM F79) and is 4mm thick. Symmetrical, the femoral components can be used on right or left knees. Cement pockets are cast into the components to provide a minimum 1mm cement mantle. The femoral component is available in four sizes.
The tibial component is manufactured from ultra-high molecular weight polyethylene. A cemented metal backed tibial component is also available. Both tibial components are available in five sizes and four thicknesses.
The subject of this Special 510(k) submission is the modification to the implant/bone interface of the femoral component and the elimination of the smallest size femoral component.
The provided text describes a Special 510(k) submission for a modification to an existing medical device, the UC-PLUS Solution Unicondylar Knee. This type of submission focuses on demonstrating that the modified device is substantially equivalent to its predicate device, primarily through non-clinical testing.
Here's an analysis of the provided information in the context of acceptance criteria and a study:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Structural Integrity & Fatigue Loading (due to fin height modification) | The change in fin height of the femoral component resulted in no increased risks and decreased the stresses in the component due to fatigue loading. |
| Equivalence to Predicate Device (K982859) | The modified component is equivalent in terms of indications, usage, and materials. |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: The document does not specify a distinct "test set" in the context of a clinical study or a large number of physical units. The testing described is non-clinical, focusing on the mechanical properties of the femoral component. Therefore, the "sample size" would refer to the number of femoral components subjected to stress and fatigue analysis. This number is not explicitly stated but would likely be a small number of physical samples or computational models.
- Data Provenance: The data is derived from non-clinical tests conducted on the device's femoral component. The provenance is internal testing performed by PLUS Orthopedics. No geographical origin of data (country) is mentioned, nor is it described as retrospective or prospective in a clinical sense.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This question is not applicable in the traditional sense of clinical studies with expert-established ground truth. The "ground truth" for the non-clinical tests is established by engineering principles and validated testing methods for material strength, stress distribution, and fatigue. There are no "experts" in the sense of clinical reviewers establishing diagnostic ground truth. The experts involved would be biomechanical engineers or materials scientists conducting the tests and interpreting the results, but their number and specific qualifications are not detailed.
4. Adjudication Method for the Test Set
This is not applicable. Adjudication methods (like 2+1, 3+1) are used in clinical studies where multiple human readers or experts evaluate cases. The study described is a non-clinical, engineering-based assessment.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done
No, an MRMC comparative effectiveness study was not done. This type of study assesses how human readers perform with and without AI assistance, which is irrelevant for a mechanical knee implant modification.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
This question is not applicable. There is no AI algorithm or standalone software component described for this device. The device is a physical knee implant.
7. The Type of Ground Truth Used
The ground truth used in this context is engineering and materials science standards and principles. This involves:
- Physical measurements of stress and strain.
- Fatigue testing results.
- Comparison against established biomechanical performance requirements for knee implants.
- Analytical or computational models demonstrating reduced stress.
8. The Sample Size for the Training Set
This is not applicable. There is no mention of a "training set" as this is not a machine learning or AI-based device. The design, analysis, and testing of the implant are based on established engineering principles and prior knowledge.
9. How the Ground Truth for the Training Set was Established
This is not applicable as there is no training set.
§ 888.3530 Knee joint femorotibial metal/polymer semi-constrained cemented prosthesis.
(a)
Identification. A knee joint femorotibial metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace part of 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 consist of a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a tibial component made of ultra-high molecular weight polyethylene and is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.