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The Ascension® NuGrip® CMC Implant is intended to replace the proximal end of the first metacarpal in cases of rheumatoid arthritis, traumatic arthritis, osteoarthritis, or post fracture deformation or bone loss which present as either a painful, unstable thumb or a thumb with limited range of motion.

The Ascension NuGrip CMC Implant is a single-use, uncemented one-piece implant for the basal thumb joint. It is constructed of a graphite core encased in a layer of pyrolytic carbon. The device is offered in 9 different combinations of 3 head and 4 stem sizes. The NuGrip represents incremental design modifications to the Ascension PyroHemiSphere, including an extended proximal spherical head, a collar at the head base, modified stem geometry, and additional implant sizes.

The provided text is a K112278 510(k) premarket notification for the Ascension® NuGrip® CMC Implant. It describes the device, its intended use, and the basis for substantial equivalence to predicate devices. However, it explicitly states that no clinical performance data were needed to support substantial equivalence of the design modifications.

Therefore, there is no information in the provided text to answer most of your questions, as they pertain to clinical studies and performance data.

Here's what can be extracted based on the document:

1. A table of acceptance criteria and the reported device performance:

Since no clinical performance data was provided or deemed necessary, there are no specific clinical acceptance criteria or reported device performance metrics in the context of a clinical study. The device's substantial equivalence was based on non-clinical performance data and material/process equivalence to predicate devices.

2. Sample size used for the test set and the data provenance:

Not applicable, as no clinical performance data was provided.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

Not applicable, as no clinical performance data was provided.

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

Not applicable, as no clinical performance data was provided.

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 device is an implant, not an AI-assisted diagnostic tool.

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

Not applicable. This device is an implant, not an algorithm.

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

Not applicable, as no clinical performance data was provided. The "ground truth" for this submission was based on the substantial equivalence of the device's materials, design modifications, and non-clinical performance to existing, cleared predicate devices.

8. The sample size for the training set:

Not applicable, as no clinical performance data was provided.

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

Not applicable, as no clinical performance data was provided.

Summary based on the provided text:

The information explicitly states: "No clinical performance data were needed to support substantial equivalence of the design modifications." This means the regulatory pathway for this device did not require a clinical study with human patients to demonstrate safety and effectiveness for this specific submission. Instead, substantial equivalence was established through:

• Identical materials and processes to the predicate Ascension® PyroHemiSphere® CMC implant.
• Non-clinical performance data and analysis, including:
  • CMC Joint Biomechanics Review
  • Static Compression-Bending Testing
  • Basal Thumb Implant Endurance Testing
  • System Verification Report/Strength Analysis
  • PyroCarbon Wear Characteristics Analysis
• The determination that design modifications do not raise new issues of safety or effectiveness.
• Unchanged indications for use and intended function from the predicate devices.

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The Ascension® CMC is intended to replace the proximal end of the first metacarpal in cases of rheumatoid arthritis, traumatic arthritis, osteoarthritis or post fracture deformation or bone loss which present as either a painful, unstable thumb, or a thumb with limited range of motion. This is an uncemented prosthesis designed for press fit use only.

The Ascension® CMC is intended for use as a hemi joint replacement for the base of the first metacarpal of the carpometacarpal (CMC) joint. The Ascension CMC is a one component prosthesis having a saddle configuration articular surface which bears against the mating saddle articular surface of the trapczium. The saddle design allows for flexion-extension joint motion and abduction-adduction motion. It is designed to be a press fit device. Each device is comprised of a pyrocarbon layer encasing a machined graphite substrate. The graphite substrate material is impregnated with a small amount (I atomic percent) of tungsten. This small amount of tungsten renders the graphite substrate radiopaque. The device is provided sterile in packaging containing a single device.

The provided text describes a 510(k) Premarket Notification for the Ascension® CMC device, a wrist joint carpal trapezium polymer prosthesis. The document focuses on demonstrating substantial equivalence to a predicate device rather than presenting a study to prove the device meets specific acceptance criteria. Therefore, most of the requested information regarding study design, sample sizes, expert involvement, and ground truth establishment is not available in the provided text.

Here's what can be extracted and what is missing:

1. Table of Acceptance Criteria and Reported Device Performance

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

• Sample Size for Test Set: Not specified.
• Data Provenance: Not specified (e.g., country of origin, retrospective or prospective). The text only mentions "Performance tests conducted on Ascension CMC devices," "in vitro material biocompatibility tests," and "pre-clinical animal tests."

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

• Not applicable/Not specified, as no human-expert-driven ground truth establishment for a diagnostic/AI device is described. The "ground truth" here refers to the results of the performance, biocompatibility, and animal tests.

4. Adjudication Method for the Test Set

• Not applicable/Not specified, as no human-expert-driven adjudication process for a diagnostic/AI device is described.

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

• No, a Multi Reader Multi Case (MRMC) comparative effectiveness study was not done. This device is a prosthesis, not an AI or diagnostic imaging device that would typically involve human readers.

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

• Not applicable. This device is a medical implant (prosthesis), not a standalone algorithm.

7. The Type of Ground Truth Used

• The "ground truth" implicitly used for demonstrating substantial equivalence are the results of specific engineering performance tests, in vitro material tests, and pre-clinical animal studies. These tests are presumed to provide definitive data on the device's characteristics and safety.

8. The Sample Size for the Training Set

• Not applicable/Not specified. There is no mention of a "training set" for an algorithm, as this is a medical device (prosthesis).

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

• Not applicable/Not specified. There is no mention of a "training set" or its ground truth establishment for an algorithm.

Summary of the Study type based on the provided text:

The study described is a demonstration of substantial equivalence to a predicate device (Ascension® PHS, K041451) through:

• Performance tests on Ascension CMC devices.
• In vitro material biocompatibility tests.
• Pre-clinical animal tests.

The goal of these "tests" or "studies" was to show that the Ascension® CMC performs as intended and is as safe and effective as the previously cleared predicate device, rather than to meet specific, quantifiable acceptance criteria that are typically established for novel diagnostic or AI-powered devices. The success criterion here is the FDA's determination of "substantial equivalence."

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