(434 days)
The 4WEB Medical Ankle Truss System (ATS) is for use as an accessory to the Stryker T2 Ankle Arthrodesis Nail or the Stryker Valor Hindfoot Fusion Nail as part of a tibiotalocalcaneal fusion construct in a salvage procedure following failed ankle arthrodesis or failed ankle arthroplasty for patients at risk for loss of limb. The ATS is not intended for standalone use.
The anatomical landmarks necessary for the design and creation of ATS devices that are patient matched must be present and identifiable on appropriate radiography scans. The ATS is intended for use with autograft and/or allogenic bone graft comprised of cancellous and/or corticocancellous bone graft.
The 4WEB Medical Ankle Truss System (ATS) is a permanently implanted device intended to provide mechanical support as an accessory to a tibiotalocalcaneal nail intended to fuse the tibiotalocalcaneal joint in a salvage procedure following a failed ankle arthrodesis or a failed ankle arthroplasty for patients at risk for loss of limb. ATS devices are titanium alloy (Ti6Al4V) structures in spherical or cuboidal configurations. The ATS device has an open architecture truss designed to provide structural support with open space throughout the implant to allow fusion. ATS devices are intended for use with the Stryker T2 Ankle Arthrodesis Nail or the Stryker Valor Hindfoot Fusion Nail as part of a tibiotalocalcaneal (TTC) fusion system.
The provided FDA 510(k) summary (K230088) for the Ankle Truss System (ATS) does not contain the detailed information necessary to fully answer all aspects of your request regarding acceptance criteria and a study proving device conformance. The document primarily focuses on demonstrating substantial equivalence to predicate devices based on non-clinical and limited clinical performance evaluations.
Here's a breakdown of what can be extracted and what is missing, based on the provided text:
Device: Ankle Truss System (ATS) (K230088)
1. Table of acceptance criteria and the reported device performance
The document does not explicitly state specific acceptance criteria in a quantitative or tabular format for the device's performance. It mentions "Effectiveness endpoints included fusion, pain, and functional outcomes for the subject and control treatments" in the clinical evaluation section, but it does not provide target values or thresholds for these. Similarly, for non-clinical testing, it lists the types of tests performed (ASTM F2077, ASTM F1264, Corrosion, Wear) but doesn't detail the acceptance criteria or the reported device performance against those criteria.
2. Sample size used for the test set and the data provenance
- Sample Size: The document mentions a "retrospective, single arm, multi-center evaluation of the ATS device" but does not specify the sample size (number of patients enrolled or number of ATS devices evaluated) in this clinical study.
- Data Provenance: The study was a "retrospective, single arm, multi-center evaluation." The country of origin is not specified, but given the FDA submission, it's highly probable the centers are within the United States.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
This information is not provided in the document. The study design does not appear to involve expert-driven ground truth establishment in the way typically seen for diagnostic AI or imaging devices. The "effectiveness endpoints" (fusion, pain, functional outcomes) and "safety outcomes" (adverse events, SSSI rates) would typically be gathered from patient records, imaging reports, and clinical assessments, rather than a panel of experts specifically establishing a "ground truth" for each case in the test set.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
This information is not provided and is generally not applicable to the type of clinical evaluation described for an implantable device assessing outcomes like fusion, pain, and functional improvement. Adjudication methods like 2+1 or 3+1 are more common in studies evaluating reader performance for diagnostic tasks where ground truth might be ambiguous or require expert consensus.
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
- MRMC Study: No, an MRMC comparative effectiveness study was not performed. This type of study is relevant for evaluating the impact of AI on human reader performance, particularly in diagnostic imaging. The ATS is an implantable device, not an AI diagnostic tool.
- Effect Size: Therefore, effect size related to human reader improvement with AI assistance is not applicable and not provided.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Standalone Performance: No, a standalone performance evaluation of an algorithm was not performed. The ATS is a physical implantable device, not an AI algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
For the clinical evaluation, the "ground truth" or primary data used to assess effectiveness and safety were likely derived from:
- Outcomes Data: "fusion, pain, and functional outcomes" derived from patient follow-up, clinical assessments, and potentially imaging (to assess fusion).
- Adverse Event Data: "device and procedure related adverse events and rates of subsequent secondary surgical intervention (SSSI)" derived from patient medical records.
8. The sample size for the training set
This is not applicable as the ATS is a physical implant, not a machine learning model that requires a training set in the conventional sense. The "design and creation of ATS devices that are patient matched" suggests that individual devices might be tailored, but this is a design process, not an AI training process.
9. How the ground truth for the training set was established
This is not applicable for the same reasons as #8.
§ 888.3020 Intramedullary fixation rod.
(a)
Identification. An intramedullary fixation rod is a device intended to be implanted that consists of a rod made of alloys such as cobalt-chromium-molybdenum and stainless steel. It is inserted into the medullary (bone marrow) canal of long bones for the fixation of fractures.(b)
Classification. Class II.