(274 days)
The Kinos Axiom Total Ankle System is indicated for patients with ankle joints damaged by severe rheumatoid, posttraumatic, or degenerative arthritis.
The Kinos Total Ankle System is additionally indicated for patients with failed previous ankle surgery.
The Kinos Axiom Total Ankle System is intended for cement use only.
The subject Kinos Axiom Total Ankle System is an implant and instrument system designed to preserve motion in patients with ankle arthritis. The device is a fixed bearing and semi-constrained implant construct, intended for replacement of the articulating surfaces of the ankle that have been affected by a disease state or injury. The device provides limited mobility to a patient by restoring alignment of the articulating surfaces, reducing pain and providing flexion-extension movement within the ankle joint. The device is intended to be used with bone cement. The subject Kinos Axiom Total Ankle System comprises three implant components – a tibial implant affixed to the tibia, a bearing implant assembled to the tibial implant and talar implant affixed to the talus. The tibial implant and bearing implant, assembled intraoperatively, function together and articulate with the talar implant to create a fixed bearing prosthesis, replacing the articulating surface of the tibial-talar joint.
This document describes a medical device submission (K192778) for the Kinos Axiom Total Ankle System. It does not contain information about acceptance criteria or a study proving device performance as typically understood in the context of an Artificial Intelligence (AI) or machine learning device.
The Kinos Axiom Total Ankle System is a physical implant, not a software or AI-driven diagnostic/prognostic device, so the usual metrics associated with AI device performance (like sensitivity, specificity, AUC) and relevant study designs (like MRMC studies) are not applicable here.
The "studies" mentioned are non-clinical analyses of the physical implant's mechanical properties, material safety, and biocompatibility, which are standard for orthopedic implants.
Here's a breakdown of the requested information based only on the provided text, acknowledging that many categories will be N/A due to the nature of the device:
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A table of acceptance criteria and the reported device performance
- Acceptance Criteria: The document states that the non-clinical analysis shows the device "can be expected to perform at least as well as the legally marketed predicates referenced above." The specific quantitative acceptance criteria (e.g., minimum fatigue life, maximum wear rate) from the ASTM and ISO standards would be detailed in the full submission, but are not provided in this summary.
- Reported Device Performance: The summary indicates that the "results of this analysis show that the subject Kinos Axiom Total Ankle System can be expected to perform at least as well as the legally marketed predicates referenced above." No specific quantitative performance metrics are provided in this summary.
Acceptance Criteria (General) Reported Device Performance (General) Performed at least as well as predicate devices Performed at least as well as predicate devices based on non-clinical analyses (Fatigue, Constraint, Contact Area, Strength, Wear, Range of Motion, Biocompatibility, Pyrogenicity) -
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 applicable in the context of an observational/clinical test set for AI. The "test set" here refers to physical samples of the implant undergoing mechanical and biological testing. The specific number of implant samples for each test (e.g., how many underwent fatigue testing) is not specified.
- Data Provenance: Not applicable in the context of patient data. The "data" comes from engineering and laboratory testing of the device itself.
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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)
- Not applicable. Ground truth for an AI device involves expert consensus on medical images or clinical outcomes. For this physical implant, performance is assessed against engineering standards and material properties, not clinical expert readings.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not applicable. This is relevant for clinical outcome adjudication or image interpretation, not for mechanical testing of a physical device.
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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. Not applicable, as this is a physical implant, not an AI-assisted diagnostic tool. No clinical study or MRMC study was required for its 510(k) clearance ("n/a – no clinical evidence was required to determine substantial equivalence").
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable. This is a physical implant, not an algorithm.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- For the non-clinical tests, the "ground truth" is defined by established engineering and biological standards (e.g., ASTM F2665 for fatigue and wear, ISO 10993-1 for biocompatibility). The device's performance is compared against the requirements and benchmarks set by these standards and against the performance of predicate devices.
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The sample size for the training set
- Not applicable. This is not an AI device that requires a training set.
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How the ground truth for the training set was established
- Not applicable.
§ 888.3110 Ankle joint metal/polymer semi-constrained cemented prosthesis.
(a)
Identification. An ankle joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an ankle joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces and has no linkage across-the-joint. This generic type of device includes prostheses that have a talar resurfacing component made of alloys, such as cobalt-chromium-molybdenum, and a tibial resurfacing 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.