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1. When used as a hemi-hip replacement system, it is intended for osteo-, rheumatoid, and post-traumatic arthritis of the hip with minimal involvement of the corresponding acetabulum, femoral head or neck fractures, aseptic necrosis of the femoral head, previous failed hip arthroplasty where there is evidence of sufficient bone quality to adequately set the implant.
2. When used as a total hip replacement system, it is intended for osteo-, rheumatoid, and post-traumatic arthritis of the hip with minimal involvement of the corresponding acetabulum, femoral head or neck fractures, aseptic necrosis of the femoral head, previous failed hip arthroplasty where there is evidence of sufficient bone quality to adequately set the implant.
3. In addition, the NexFlex Total Hip System is intended for cases where alternative modes of treatment appear less preferable and the associated risks of a total hip replacement are thought to be acceptable. It is intended for severely disabled joints, which could result from arthritis or late stages of avascular necrosis and revisions of unsuccessful acetabular cup arthroplasty and/or femoral procedure.

The NexFlex™ Total Hip System is a sterile total or hemi-hip replacement system. It consists of a series of femoral and acetabular implants that are used to help restore patient range of motion and aid in the treatment of other deformities as histor in the Indications for Use. The purpose of this 510(k) is to provide for HA coated hip sterns and acetabular cups. This submission also includes additions / modifications to the and accedural under formal change control procedures.

The provided text is a 510(k) summary for the NexFlex™ Total Hip System. This document focuses on demonstrating substantial equivalence to predicate devices rather than providing the results of a primary clinical or performance study with defined acceptance criteria and detailed statistical analysis as would be expected for a novel AI/software medical device.

Therefore, many of the requested elements for an AI/software device cannot be extracted directly from this document. However, I can provide the information that is present and explain why other sections are not applicable.

Here's the breakdown based on the provided text:

1. Table of acceptance criteria and the reported device performance

Explanation: In a 510(k) submission, the primary "acceptance criterion" is often a demonstration of substantial equivalence to a predicate device. For mechanical components like hip implants, this is typically proven through bench testing (fatigue, wear, etc.) and material characterization (biocompatibility). Explicit numerical acceptance criteria and a detailed statistical comparison with a confidence interval, as common for AI devices, are not typically found in these types of summarized 510(k) documents.

2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective)

• Sample Size for Test Set: Not specified. The document mentions "Fatigue testing and microstructure examination" but does not detail the number of samples or specimens used in these tests.
• Data Provenance: Not specified. These are likely bench test results, not human patient data.

3. 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. This document describes mechanical and biocompatibility testing of a physical medical device (hip implant components), not performance evaluation of an AI-based diagnostic or prognostic tool that would require expert-established ground truth.

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set

• Not applicable. This relates to expert consensus for ground truth establishment, which is not relevant to the type of testing described here.

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

• Not applicable. This describes the evaluation of an AI/software device, which the NexFlex™ Total Hip System is not.

6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done

• Not applicable. This describes the evaluation of an AI/software device, which the NexFlex™ Total Hip System is not.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

• Mechanical and Material Standards: The "ground truth" for the performance claims would be established by recognized engineering and material standards for orthopedic implants (e.g., ISO standards for fatigue testing, material properties, and biocompatibility). The document states that the test results "demonstrated that the mechanical performance and biocompatibility characteristics are at least comparable to, if not better than, those of the predicate device," implying a comparison against established benchmarks or the predicate device's known performance.

8. The sample size for the training set

• Not applicable. There is no "training set" as this is not an AI/machine learning device.

9. How the ground truth for the training set was established

• Not applicable. There is no "training set" as this is not an AI/machine learning device.

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The NexFlex Total Knee System is indicated for:

• Painful, disabling joint disease resulting from rheumatoid arthritis, post-traumatic . arthritis, osteoarthritis, or degenerative arthritis
• . Failed osteotomies, unicompartmental replacement, or total knee replacement
• Post-traumatic loss of knee joint configuration and function .
• Moderate varus, valgus, or flexion deformity in which the ligamentous structures can . be returned to adequate function and stability

The NexFlex Total Knee System is intended for cemented use only.

The NexFlex Total Knee System consists of femoral components, tibial base components, tibial inserts, all-polyethylene tibial components, cancellous bone screws, a tibial screw hole cap, tibial stem extensions, and patellar components. The components of this system are designed to be used together and cannot be used as part of another system, nor can components of another system be incorporated into use with the NexFlex Total Knee System.

NexFlex femoral components are manufactured from cobalt-chromium alloy and are available in a range of sizes and in left and right orientations. They are available with or without a commercially pure titanium plasma sprayed inner surface.

Tibial base components are manufactured from titanium (Ti-6Al-4V) alloy and are available in a range of sizes. They are available with or without a commercially pure titanium plasma sprayed distal surface.

Tibial inserts are manufactured from ultra-high molecular weight polyethylene and are available in a range of sizes to match the tibial base components. The distal side of the tibial inserts has geometry to allow a mechanical lock to the tibial base components of corresponding size. The proximal side of the tibial inserts has geometry that allows articulation with the femoral components. Tibial inserts are available with two different proximal geometries, allowing for different amounts of constraint and contact area with the femoral components. A number of thicknesses of inserts are offered.

All-polyethylene tibial components are manufactured from ultra-high molecular weight polyethylene and are available in a range of sizes and thicknesses. These components have distal geometry similar to the tibial base components and proximal geometry similar to the tibial inserts.

Cancellous bone screws are manufactured from titanium (Ti-6Al-4V) alloy and are available in a range of lengths. The screws are designed to go through the tibial base component to secure it to the proximal tibia.

Tibial screw hole caps are manufactured from titanium (Ti-6Al-4V) alloy. They are designed to thread into the tibial base components to cover the screw holes when a cancellous bone screw is not used.

Tibial stem extensions are manufactured from titanium (Ti-6A1-4V) alloy and are available in a range of diameters and lengths. The stems are designed to mate with the tibial base components by means of a mechanical engagement.

Patellar components are manufactured from either ultra-high molecular weight polyethylene or a combination of ultra-high molecular weight polyethylene and titanium (Ti-6Al-4V) alloy. They are designed with posterior geometry that allows articulation with the femoral components. Patellar components with titanium backing have a commercially pure titanium plasma spraved anterior surface.

Here's an analysis of the provided text regarding the NexFlex Total Knee System, focusing on acceptance criteria and supporting studies:

Based on the provided 510(k) Summary for the NexFlex Total Knee System, the product is a medical device (a semi-constrained total knee prosthesis) submitted for premarket notification to the FDA. For such devices, acceptance criteria and studies typically focus on demonstrating substantial equivalence to legally marketed predicate devices, rather than establishing de novo performance metrics like sensitivity/specificity for a diagnostic AI. The "acceptance criteria" here implicitly refer to meeting the safety and effectiveness standards demonstrated by the predicate devices through mechanical testing and comparison of design, function, materials, and indications for use.

1. Table of Acceptance Criteria and Reported Device Performance

2. Sample Size Used for the Test Set and Data Provenance

The provided 510(k) summary does not mention a clinical "test set" or data provenance in the context of human studies for performance or AI applications. The "testing" referred to is mechanical testing of the device itself.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications

This information is not applicable to the provided document. The submission pertains to a knee prosthesis, not an AI/diagnostic device that would require expert-established ground truth from a test set of data.

4. Adjudication Method for the Test Set

This information is not applicable to the provided document for the same reasons as #3.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was Done

No, an MRMC comparative effectiveness study was not done, and this type of study is not relevant for a knee prosthesis 510(k) submission. These are typically for diagnostic devices, often involving AI.

6. If a Standalone (i.e. algorithm only, without human-in-the-loop performance) was Done

No, a standalone algorithm performance study was not done. The NexFlex Total Knee System is a physical medical device, not an algorithm or AI.

7. The Type of Ground Truth Used

The "ground truth" in this context is established by the performance of the predicate devices and the established safety and effectiveness of the materials and design principles used in total knee prostheses. For the mechanical testing, the "ground truth" is engineering standards and the ability to withstand simulated physiological loads without failure.

8. The Sample Size for the Training Set

This information is not applicable as the device is not an AI/algorithm and therefore does not have a "training set."

9. How the Ground Truth for the Training Set was Established

This information is not applicable for the same reasons as #8.

Summary of the Study that Proves the Device Meets Acceptance Criteria:

The study that proves the NexFlex Total Knee System meets its implicit acceptance criteria (which are primarily substantial equivalence to predicate devices and mechanical integrity) is described as "Non-Clinical Performance Data":

• Study Type: Mechanical testing.
• Methodology: Performed in accordance with the "recommended testing listed in the Draft Guidance for the Preparation of Premarket Notifications (510(k)s) for Cemented, Semi-Constrained Total Knee Prostheses." This guidance likely specifies various wear, fatigue, static strength, and other biomechanical tests relevant to knee implants.
• Results/Conclusion: "Testing indicated that the system is capable of withstanding in vivo loading without failure."
• Comparison: The results of these mechanical tests, coupled with the comparison of the NexFlex system's design, function, materials, and indications for use to the Miller/Gallante Total Knee System (Zimmer, Inc.), AGC Total Knee System (Biomet, Inc.), AMK Total Knee System (DePuy, a Johnson Company), and Series 7000 Total Knee System (Stryker/Osteonics), formed the basis for the FDA's determination of substantial equivalence. This determination effectively means the device meets the regulatory acceptance criteria for market entry.

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