(27 days)
Total ankle arthroplasty is intended to give a patient limited mobility by reducing pain, restoring alignment and replacing the flexion and extension movement in the ankle joint. Total ankle arthroplasty is indicated for patients with ankle joints damaged by severe rheumatoid, posttraumatic, or degenerative arthritis.
The ankle prosthesis is additionally indicated for patients with a failed previous ankle surgery.
CAUTION: The ankle prosthesis is intended for cement use only.
The INBONE™ Total Ankle System consists of tibial trays, talar domes, poly inserts, tibial stems and talar stems.
The design features of the INBONE™ Total Ankle System device modification are substantially equivalent to the design features of the predicate INBONE™ Total Ankle System devices.
This document describes a 510(k) premarket notification for a modified INBONE™ Total Ankle System. The submission focuses on demonstrating substantial equivalence to a legally marketed predicate device rather than presenting a study to prove performance against specific acceptance criteria in the context of typical AI/medical device efficacy studies.
Here's an analysis of the provided information based on your requested points, highlighting that this is a device modification approval and not a de novo device efficacy study:
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Table of Acceptance Criteria and the Reported Device Performance:
Acceptance Criteria Reported Device Performance Criterion: Perform at least as well as the legally marketed predicate device. This is implicitly based on:
- Material equivalence
- Identical indications for use
- Similar design features (despite slight difference in overall length of new size)
- Mechanical integrity (specifically fatigue life) | Performance:
- The modified device utilizes the same materials as the predicate.
- The indications for use are identical to the predicate device.
- The design features are similar; the modification is the addition of a new size, differing only in overall length from existing sizes.
- Fatigue testing was performed. The results show that the additional size "can be expected to perform at least as well as the legally marketed predicate." This is the key "performance" reported to meet the substantial equivalence claim.
- Conclusion: "the subject devices can be expected to perform at least as well as the predicate devices." |
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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. This approval is based on a fatigue test for a mechanical device, not a performance study on a "test set" of patients or data in the context of AI/diagnostic devices. The sample size would refer to the number of devices or components tested in the fatigue assessment. This specific number is not provided in a way that relates to clinical "test sets."
- Data Provenance: Not applicable in the traditional sense of patient data. The data originates from mechanical fatigue testing performed on the device or its components. The location of testing is not specified, nor is whether it was prospective (new tests for this submission) or retrospective (re-analysis of previous test data, though unlikely for a new size).
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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. There is no "ground truth" derived from expert consensus on a test set of clinical cases. The "ground truth" for mechanical testing is typically defined by engineering specifications and standards for device breakage or wear, with evaluation performed by engineers or testing laboratories.
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Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Not applicable. This concept is relevant for clinical or diagnostic studies requiring expert review, which is not the nature of this submission.
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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:
- Not applicable. This is not an AI-assisted diagnostic device, nor does it involve human readers interpreting data. It's a mechanical implant. The document explicitly states "B.2. Substantial Equivalence - Clinical Evidence N/A".
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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 orthopedic implant, not an algorithm.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- As this is a mechanical device, the "ground truth" for its performance is established by engineering standards and specifications for mechanical integrity and fatigue life, demonstrated through fatigue testing. The comparison is to a predicate device's established performance under similar testing conditions.
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The sample size for the training set:
- Not applicable. This is not an AI or machine learning device requiring a training set.
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How the ground truth for the training set was established:
- Not applicable.
Summary of the K103374 Submission:
This 510(k) submission is for a device modification (addition of a new size) to an existing orthopedic implant (INBONE™ Total Ankle System). The primary method used to demonstrate substantial equivalence, rather than meeting specific performance criteria against a clinical "ground truth," was:
- Comparison of Technological Characteristics: Showing identical indications, similar design features (with minor modification for size), and use of the same materials.
- Non-Clinical Evidence: Specifically, fatigue testing of the new size. The acceptance criterion was that the new size performs "at least as well as the legally marketed predicate" in terms of mechanical fatigue. The study essentially involved a direct comparison to the predicate's known or expected fatigue performance, implied to be successful if it met industry standards for such devices.
- Absence of Clinical Evidence: The submission explicitly states "N/A" for clinical evidence, indicating that no new human clinical trials were conducted or deemed necessary for this specific device modification.
Therefore, the "study" proving the device meets the (implied) acceptance criteria is the fatigue testing that demonstrated equivalent mechanical performance to the predicate device.
§ 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.