(125 days)
The GMK Total Knee System is designed for cemented use in total knee arthroplasty, if there is evidence of sufficient sound bone to seat and support the components. This knee replacement system is indicated in the following cases:
• Severely painful and/or disabled joint as a result of arthritis, traumatic arthritis, rheumatoid arthritis or polyarthritis.
- · Avascular necrosis of femoral condyle.
- Post traumatic loss of joint configuration.
- · Primary implantation failure.
Tibial wedges cemented are to be attached to the tibial baseplate with both the fixing cvlinders and bone cement.
The screwed tibial augments are for screwed fixation to the tibial baseplate.
In case a semi-constrained liner is used, an extension stem must be implanted both on the tibial and on the femoral components.
In case a GMK Revision tibial tray is used, an extension stem must be implanted.
The GMK Extension is a line extension to the Medacta GMK Total Knee System and consists of the following components which are all made from Co-Cr-Mo (ISO 5832-4):
- . Femur STD cemented #0, Left and Right
- . Femur PS cemented #0, Left and Right
- Femur STD cemented #1 and #7 Narrow, Left and Right .
- . Femur PS cemented #1 and #7 Narrow, Left and Right
This document is a 510(k) premarket notification for the "GMK Total Knee System," specifically concerning a line extension called "GMK Extension." The FDA has determined the device is substantially equivalent to legally marketed predicate devices.
Here's an analysis of the acceptance criteria and study information provided, attempting to fill in the requested details:
-
Table of Acceptance Criteria and Reported Device Performance:
Acceptance Criteria Reported Device Performance Not explicitly stated as specific numerical criteria in the provided text. The criteria are broadly described as "predefined acceptance criteria" based on standards, FDA guidance, and comparison to predicate devices for mechanical strength, range of motion, constraints, and contact pressures/wear. The GMK Extension "was compared to the worst case predicate device in terms of mechanical strength, range of motion, constraints to prevent risk of dislocation, and contact pressures/wear and it was determined that the GMK Extension is not worst case." The submission concludes that the GMK Extension is "substantially equivalent" to its predicate devices. -
Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective):
- Sample size: Not specified. The document mentions "performance testing" but does not give specific numbers for physical samples or simulated cases used in the testing.
- Data provenance: Not specified. It's generally inferred that the testing would have been conducted by Medacta International or a contracted lab, likely in Switzerland (where Medacta is headquartered as per the contact information) or the USA. The type of study is a design verification physical/mechanical testing, not human clinical trial data (retrospective or prospective).
-
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This question is largely not applicable to the type of study described. This 510(k) summary focuses on mechanical performance testing of a knee implant, not an AI or diagnostic device that requires expert-established ground truth from images or clinical data. The "ground truth" here is the physical/mechanical performance of the device against established engineering standards and predicate device performance.
-
Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable. As above, this pertains to clinical/diagnostic studies where human review or consensus is used for ground truth. The testing mentioned is engineering/mechanical.
-
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 not an AI or diagnostic imaging device.
-
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not applicable. This is not an AI device.
-
The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- The "ground truth" in this context is based on pre-defined acceptance criteria derived from industry standards, FDA guidance, and mechanical performance benchmarks established by the predicate devices. This is a form of engineering performance ground truth, not clinical ground truth.
-
The sample size for the training set:
- Not applicable. This device is a mechanical implant, not an AI system that requires a training set.
-
How the ground truth for the training set was established:
- Not applicable. As this is not an AI device, there is no training set and no ground truth establishment for a training set.
§ 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.