(227 days)
The GMK® knee prosthesis 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, theumatoid 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 cylinders 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 femoral components. In case a GMK Revision tibial tray is used, an extension stem must be implanted.
The GMK Sphere Tibial Insert Flex is a line extension to the GMK Sphere Total Knee System and is comprised of the following products:
- Tibial Insert Fixed Flex: Left and Right, Sizes 1-6, 10-20mm (including intermediate ● sizes 11mm and 13mm) UHMWPE (ISO 5834-2)Type 1, Fixation Screw: Ti6Al5V (ISO 5232-3)
The purpose of this submission is to modify the surgical technique provided to surgeons to show that the GMK Sphere Tibial Insert Flex titanium screws' use as optional, instead of required. This technique modification does not alter the intended use or outcomes.
This document describes a 510(k) premarket notification for the GMK® Sphere Tibial Insert Flex. The purpose of this submission is to modify the surgical technique for the device, making the use of titanium screws optional instead of required, and to introduce additional thickness sizes.
Here's an analysis of the provided text in relation to acceptance criteria and supporting studies:
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Table of Acceptance Criteria and Reported Device Performance:
The document does not explicitly present a table of acceptance criteria with corresponding reported device performance metrics in the way one might expect for a diagnostic or AI-driven device. Instead, the "acceptance criteria" are implied by the demonstration of substantial equivalence to predicate devices and the lack of new safety and effectiveness questions arising from the proposed changes. The performance is assessed through various tests and analyses.
Acceptance Criterion (Implied) Reported Device Performance Biocompatibility "Biocompatibility testing conducted on the predicate devices for the same material supports the biological safety of the GMK Sphere Tibial Insert Flex. Additional testing was deemed unnecessary." Mechanical Performance (with optional screw use) "Based on the risk analysis, static analysis combined with previous static and dynamic/fatigue test on the clipping system, the GMK Sphere Tibial Insert Flex remains safe and consistent for the intended use though the fixation screw is not used." Sterilization Validation One of the analyses conducted or leveraged was "Sterilization Validation". No specific performance outcome is detailed, but the inclusion implies it met established standards. Shelf Life One of the analyses conducted or leveraged was "Shelf Life". No specific performance outcome is detailed, but the inclusion implies it met established standards. The shelf life is stated as 5 years in the comparison table (Page 5). Pyrogenicity (for applicable components, if claimed non-pyrogenic) "Limulus Amebocyte Lysate (LAL) testing was evaluated to establish the device meets pyrogen limit specifications." (Medacta does not intend to claim "non-pyrogenic" for Femoral Distal Augmentations, implying pyrogenicity was evaluated where relevant but not necessarily claimed as part of the primary device's properties). Safety and Effectiveness (overall, for modified features) "The fundamental scientific technology of the modified device has not changed relative to the predicate devices. The safety and effectiveness of the subject device is adequately supported by the substantial equivalence information, materials information, and analysis data provided..." -
Sample Size Used for the Test Set and Data Provenance:
The document describes engineering and laboratory tests rather than clinical studies with human subjects or a "test set" of patient data in the typical sense for an AI/diagnostic device. The tests mentioned include:
- Static and Dynamic/Fatigue Test on Clipping System (K090988): This test was leveraged from a previous submission (K090988). The sample size (e.g., number of components tested) for this mechanical testing is not specified in this document. The provenance is internal laboratory testing.
- Sterilization Validation, Shelf Life, LAL testing: These are standard laboratory tests conducted on device materials or products. The sample sizes for these tests are not specified, but would typically involve a statistically appropriate number of units as per relevant international standards (e.g., ISO, ASTM). The provenance is internal laboratory testing.
There is no mention of country of origin of data or whether it was retrospective or prospective, as it pertains to device testing, not patient data analysis.
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Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
This information is not applicable to this submission. This document pertains to a medical device modification and its mechanical and material properties, not an AI/diagnostic device that requires expert-established ground truth from a test set of patient data. The "ground truth" here is established through engineering principles, material science, and regulatory standards.
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Adjudication Method for the Test Set:
This is not applicable as there is no "test set" of patient cases requiring adjudication by experts. The determination of device safety and effectiveness is based on engineering analyses and adherence to material and manufacturing standards.
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Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
This is not applicable. This document describes a traditional medical device (knee prosthesis) modification and does not involve AI assistance or human reader performance.
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Standalone (Algorithm Only) Performance:
This is not applicable. The device is a physical knee prosthesis, not an algorithm.
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Type of Ground Truth Used:
The "ground truth" in this context is established by:
- Engineering principles and performance standards: For static and dynamic/fatigue testing, the "ground truth" is that the device must withstand certain forces and cycles without failure, as determined by established engineering specifications and benchmarks for similar devices.
- Material properties and biocompatibility standards: For materials, sterilization, and LAL testing, the "ground truth" is adherence to ISO standards (e.g., ISO 5834-2 for UHMWPE, ISO 5832-3/4 for metals) and regulatory limits for pyrogens, ensuring biological safety.
- Substantial equivalence: The ultimate "ground truth" for this 510(k) submission is that the modified device is "as safe and effective as the predicate devices" based on the provided data and analyses.
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Sample Size for the Training Set:
This is not applicable. There is no "training set" in the context of this traditional medical device submission. The device's design is based on established engineering principles and prior device designs, not machine learning training.
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How the Ground Truth for the Training Set Was Established:
This is not applicable as there is no 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.