(80 days)
Unicompartmental knee implants are indicated for restoring either compartment of a knee that has been affected by the following:
- · Non-inflammatory degenerative joint disease including osteoarthritis, traumatic arthritis, or avascular necrosis.
- · Correction of functional deformity.
- · Revision of previous arthroplasty procedures.
- · Treatment of fractures that are unmanageable using other techniques.
Unicompartmental knee implants are single use only and are intended for implantation only with bone cement
The subject of this traditional 510(k) is to add the MR safety information to the Journey II Unicompartmental Knee System (Journey II UK) labeling. The Journey II UK was cleared under K190085.
Journey II UK system consist of a femoral implant, tibia baseplate, modular articular insert, and requisite US Class II surgical instruments.
The package insert and label of Journey II UK is being updated to add MR conditional information.
The indication for use of Journey II UK system was updated to clarify the definition of the revision cases. This change does not change the indication for use.
The provided text describes a 510(k) premarket notification for the Smith & Nephew JOURNEY II Unicompartmental Knee System. This submission is primarily to add MR safety information to the labeling and clarify the definition of revision cases for an already cleared device (K190085).
Therefore, the "device" in question for this specific submission is essentially the MR safety information for the JOURNEY II Unicompartmental Knee System, not a new or modified implant design. The performance data presented pertains to the MR compatibility of the existing implant.
Here's the breakdown of the requested information based on the provided text:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state acceptance criteria in a quantitative format for the MR safety tests. Instead, it states that testing was conducted "as per the FDA's guidance 'Establishing Safety and Compatibility of Passive Implants in the Magnetic Resonance (MR) Environment', December 11, 2014 and the standards listed below." The implicit acceptance criterion is that the device demonstrates MR compatibility according to these standards, allowing it to be labeled as MR Conditional.
| Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|
| Conformance to ASTM F2052 for magnetically induced displacement force | Testing was conducted as per ASTM F2052. (The specific results or "passing" thresholds are not detailed, but the conclusion is that the labeling can be updated with MR conditional information, implying successful conformance.) |
| Conformance to ASTM F2213 for magnetically induced torque | Testing was conducted as per ASTM F2213. (The specific results or "passing" thresholds are not detailed, but the conclusion is that the labeling can be updated with MR conditional information, implying successful conformance.) |
| Conformance to ASTM F2182 for radiofrequency (RF) induced heating | Testing was conducted as per ASTM F2182. (The specific results or "passing" thresholds are not detailed, but the conclusion is that the labeling can be updated with MR conditional information, implying successful conformance.) |
| Conformance to ASTM F2119 for MR image artifact | Testing was conducted as per ASTM F2119. (The specific results or "passing" thresholds are not detailed, but the conclusion is that the labeling can be updated with MR conditional information, implying successful conformance.) |
| The device design, materials, and indications for use are substantially equivalent to the predicate (K190085 and K160738) | "The device design, material, and indications for use of the subject device are same as the predicate JOURNEY II UK system cleared under K190085." and "In summary, the Smith & Nephew's JOURNEY II Unicompartmental Knee System is identical in function, design features, intended use, indications for use, materials, sterilization, manufacturing methods, and operational principles as the predicate device JOURNEY II Unicompartmental Knee System cleared under K190085." |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document relates to testing of the implant's physical properties for MR compatibility, not a clinical study on patients. Therefore, the "sample size for the test set" would refer to the number of implant components tested. This information is not provided in the document. The data provenance would be laboratory testing, not patient data, and thus country of origin or retrospective/prospective does not apply in this context.
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)
This question is not applicable. The "ground truth" for MR compatibility testing is established by adherence to recognized ASTM standards and FDA guidance, performed by engineers or technicians experienced in medical device testing. It does not involve expert clinical assessment or interpretation.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable, as this is laboratory testing against standards, not a clinical assessment requiring adjudication of diagnostic findings.
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 document does not describe a comparative effectiveness study, MRMC study, or AI-assisted diagnostic device. It pertains to the MR compatibility of a knee implant.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This is not an algorithmic device.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for the performance data (MR compatibility) is defined by the ASTM test standards (ASTM F2052, ASTM F2213, ASTM F2182, ASTM F2119) and FDA guidance ("Establishing Safety and Compatibility of Passive Implants in the Magnetic Resonance (MR) Environment"). These standards provide the methodology and criteria for evaluating the physical interactions of an implant with an MR environment.
8. The sample size for the training set
Not applicable. This is not a study involving a training set for an AI/machine learning model.
9. How the ground truth for the training set was established
Not applicable.
§ 888.3520 Knee joint femorotibial metal/polymer non-constrained cemented prosthesis.
(a)
Identification. A knee joint femorotibial metal/polymer non-constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits minimally (less than normal anatomic constraints) translation in one or more planes. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral condylar resurfacing component or components made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components made of ultra-high molecular weight polyethylene and are intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.