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The CORNERSTONE® PSR device is indicated for cervical interbody fusion procedures in skeletally mature patients with cervical disc disease at one level from the C2-C3 disc to the C7-T1 disc. Cervical disc disease is defined as intractable radiculopathy and/or myelopathy with herniated disc and/or osteophyte formation on posterior vertebral endplates producing symptomatic nerve root and/or spinal cord compression confirmed by radiographic studies. This device is to be used in patients who have had six weeks of non-operative treatment. The CORNERSTONE® PSR device is to be used with supplemental fixation. The CORNERSTONE® PSR device is also required to be used with autograft and is to be implanted via an open, anterior approach.

The CORNERSTONE® PSR Spinal System is designed for use as a cervical intervertebral body fusion device. The device is manufactured from medical grade polyetheretherketone (PEEK) and is to be used with autograft. The device has four degrees of lordosis. The lateral walls of the device contain openings to allow for the incorporation of bone during the fusion process. The superior and inferior surfaces of the implant are designed with teeth which interact with the surface of the vertebral endplates and helps in resisting backout.

Here is an analysis of the provided text regarding the MEDTRONIC Sofamor Danek CORNERSTONE® PSR Spinal System:

The provided documents describe a Cervical Interbody Fusion Device and its substantial equivalence determination by the FDA. The "acceptance criteria" and "study that proves the device meets the acceptance criteria" in this context refer to the mechanical performance testing conducted to demonstrate safety and effectiveness equivalent to predicate devices. It is crucial to understand that for this type of medical device (a 510(k) submission), the "acceptance criteria" is typically performance benchmarked against legally marketed predicate devices, not clinical efficacy in terms of patient outcomes in a human study.

Here's the breakdown as requested, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

Note on Acceptance Criteria: For a 510(k) submission, "acceptance criteria" for a new device are primarily demonstrated by showing "substantial equivalence" to one or more legally marketed predicate devices. This means the mechanical performance of the new device is expected to be at least as safe and effective as its predicates, which is typically proven by meeting or exceeding the performance established by those predicates in relevant pre-clinical tests. The text explicitly states, "The results of these studies were found to be substantially equivalent to legally marketed devices."

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

• Sample Size for Test Set: The document does not specify the exact number of devices tested for each mechanical test (static, dynamic, subsidence). It refers to "worst case CORNERSTONE® PSR devices" being tested, implying that representative samples were chosen to challenge the device's limits.
• Data Provenance: The studies were "pre-clinical studies," which means they were conducted in a laboratory setting, not on human subjects. No country of origin is specified for where these pre-clinical tests were performed, but the submission is to the US FDA. The data is retrospective in the sense that the mechanical tests generate data for the specific submission, and the comparison is made to established performance benchmarks of predicate devices.

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

This question is not applicable in the context of this 510(k) submission.

• Reasoning: The "test set" here refers to the physical devices undergoing mechanical stress tests, not imaging data or clinical cases requiring expert interpretation. The "ground truth" for mechanical performance is determined by physical measurements and engineering standards (e.g., ASTM F2077, ASTM F2267), not by expert consensus or interpretation of clinical data. Therefore, there were no experts used to establish "ground truth" in the way one might for diagnostic AI.

4. Adjudication Method for the Test Set

This question is not applicable in the context of this 510(k) submission.

• Reasoning: Adjudication methods like 2+1 or 3+1 are used for resolving discrepancies in expert opinions, typically for clinical data or image interpretation. Since the "test set" here refers to mechanical device performance, there's no expert interpretation or adjudication involved beyond the standard engineering and quality control processes of evaluating test results against specified performance metrics.

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

This question is not applicable for this device submission.

• Reasoning: The CORNERSTONE® PSR Spinal System is a physical implant (a medical device for cervical fusion), not an AI diagnostic tool or software. Therefore, there would be no "human readers," "AI assistance," or "MRMC comparative effectiveness study" in this context. The study performed involved mechanical testing of the implant itself.

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

This question is not applicable for this device submission.

• Reasoning: This device is a physical implant, not an algorithm or AI system. Therefore, the concept of "standalone performance" for an algorithm does not apply.

7. The Type of Ground Truth Used

• Type of Ground Truth: The ground truth used for demonstrating the device's performance was based on established engineering standards and performance characteristics of legally marketed predicate devices. This includes:
  • Mechanical Test Standards: ASTM F2077 (for static and dynamic axial compression, compression shear, torsion) and ASTM F2267 (for subsidence testing).
  • Performance of Predicate Devices: The "substantial equivalence" claim relies on the new device's mechanical performance being comparable to or better than previously approved devices (e.g., PEEK PREVAIL™ Cervical Interbody Device, AFFINITY® Anterior Cervical Cage, BAK/C® Cervical Interbody Fusion System, etc.) for which safety and effectiveness have already been established by the FDA.

8. The Sample Size for the Training Set

This question is not applicable in the context of this 510(k) submission.

• Reasoning: The "training set" concept applies to machine learning or AI models, where data is used to train an algorithm. This device is a physical implant, and its evaluation involved mechanical testing, not algorithm training.

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

This question is not applicable in the context of this 510(k) submission.

• Reasoning: As explained in point 8, there is no "training set" for a physical device like this implant. Therefore, no ground truth for a training set was established.

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