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A construct with screws attached to the pedicles of the lumbar and sacral spine (L3 to S1) and autogenous bone graft may be used only for the treatment of severe spondylolisthesis (Grade 3 and Grade 4) at the fifth lumbar - first sacral (L5-S1) vertebral joint (see warnings below). The device is intended to be implanted using a posterior surgical approach and removed after the development of a solid fusion mass.

When not used as a pedicle screw fixation system, various combinations of the Titanium Versalok Screw Assembly components are also indicated to provide temporary stability of the thoracic, thoracolumbar, or lumbar spine (T1 to S1) during bony fusion healing secondary to:

1. Unstable spinal fractures (such as fracture dislocations) or instability secondary to spinal tumors;
2. Degenerative disk diseases of the spine (defined as back pain of diskogenic origin with degeneration of the disk confirmed by radiographic studies);
3. Spinal curvatures (such as idiopathic scoliosis, neuromuscular scoliosis/kyphoscoliosis with associated paralysis or spasticity, and secondary to spinal fractures) which are:

• Progressive, despite other forms of treatment,
• Detrimental to cardiopulmonary function,
• Interfering with spinal mechanics or causing severe back pain,
• Cosmetically unacceptable, progressive, and painful.

The system is intended to provide temporary maintenance and support of the correction during the time normally needed for the fusion mass to mature. Use of spinal fixation instrumentation in children has been reported. Children should have adequate bony and soft tissue maturity to undergo implantation but need not have reached skeletal maturity.

The Titanium Versalok Screw Assembly consists of straight rods, an outer ring, cap, and polyaxial screws, and the instruments necessary to implant this specific system. The Titanium Versalok Screw Assembly is intended to provide stabilization of the spine for various indications (see below). The device is intended to be removed after solid fusion has occurred.

The device in question is the Titanium Versalok Screw Assembly, a spinal fixation device.

Based on the provided document, the device is being reviewed under a 510(k) Pre-market Notification for substantial equivalence to a predicate device, not as a novel device requiring extensive clinical trials for performance validation against acceptance criteria. Therefore, the information typically associated with establishing acceptance criteria and detailed study results for a new medical device, especially those involving AI or diagnostic accuracy, is not present.

The document indicates that "Mechanical test data was provided in the application" to demonstrate substantial equivalence. This suggests that the acceptance criteria and the "study" demonstrating compliance were likely related to engineering performance specifications (e.g., strength, fatigue, material compatibility) rather than clinical performance metrics in humans or AI algorithm accuracy.

Here's an attempt to address your request based on the limited information provided in a 510(k) summary for a spinal implant from 1999:

1. Table of Acceptance Criteria and Reported Device Performance

Given that this is a 510(k) submission for a spinal implant in 1999, the acceptance criteria would primarily be based on mechanical and material testing standards to demonstrate substantial equivalence to a predicate device. There would not be acceptance criteria related to "accuracy," "sensitivity," or "specificity" in the way one would describe an AI diagnostic device.

• Torsional Strength of screws
• Bending Strength of rods
• Pull-out strength of pedicle screws from simulated bone
• Fatigue life under cyclic loading (e.g., per ASTM F1717 for Spinal Implants or similar 1999 standards) | Met or Exceeded the mechanical performance characteristics of the predicate device (Versalok Screw Assembly) and relevant industry standards. The data provided demonstrated substantial equivalence in mechanical properties and performance. (Specific numerical results are not provided in this summary but would have been in the full submission). |
  | Material Compatibility | - Biocompatibility of Titanium alloy (e.g., per ISO 10993 or equivalent 1999 standards) | Demonstrated Biocompatibility through material testing and/or established use of the specific titanium alloy in similar medical devices. |
  | Functional Equivalence | - Compatibility of components (e.g., screw-rod interface)
• Ease of implantation (as inferred from design) | Demonstrated Functional Equivalence to the predicate device in terms of design, assembly, and intended surgical use. |

2. Sample Size for Test Set and Data Provenance

• Sample Size for Test Set: Not applicable in the context of clinical "test sets" for diagnostic accuracy or AI performance. For mechanical testing, the "sample size" would refer to the number of components or constructs tested to meet statistical power requirements for mechanical properties. This information is not detailed in the summary but would have been part of the mechanical test report.
• Data Provenance: Not applicable. The "data" here refers to mechanical test results, not clinical data from patients. The testing would have been conducted in a laboratory setting by the manufacturer or a contracted lab.

3. Number of Experts Used to Establish Ground Truth and Qualifications

• Number of Experts: Not applicable. Ground truth, in the context of an AI device or a diagnostic test, refers to a definitive diagnosis or outcome. For a spinal implant, "ground truth" relates to its physical and material properties, which are assessed through engineering tests, not expert consensus on medical images or patient outcomes for the device itself (though clinical outcomes for patients are certainly relevant post-market).
• Qualifications of Experts: The "experts" would be engineers, material scientists, and biomechanics specialists responsible for designing, testing, and interpreting the mechanical and material data, ensuring compliance with relevant standards.

4. Adjudication Method for the Test Set

• Not applicable. Adjudication methods (e.g., 2+1, 3+1) are for resolving discrepancies in expert interpretations of clinical data or images, which is not relevant to mechanical testing.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

• No, a MRMC comparative effectiveness study was not done. This type of study is specific to evaluating human reader performance, often in diagnostic imaging, and is particularly relevant for AI-assisted workflows. This device is a passive spinal implant, not an imaging or diagnostic AI tool.

6. Standalone (Algorithm Only) Performance Study

• No, a standalone performance study was not done. This concept is exclusively for AI algorithms. The Titanium Versalok Screw Assembly is a physical medical device.

7. Type of Ground Truth Used

• The "ground truth" for this device, in the context of its 510(k) submission, would be based on:
  • Engineering Specifications and Standards: The ultimate "truth" against which the device's mechanical performance is measured would be the established industry standards (e.g., ASTM standards for spinal implants) and the performance characteristics of the legally marketed predicate device.
  • Material Characterization: Scientific data on the properties of the titanium alloy used.

8. Sample Size for the Training Set

• Not applicable. There is no "training set" in the context of mechanical testing for a spinal implant. This term relates to machine learning models.

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

• Not applicable. As there is no training set, there is no ground truth establishment for it.

Summary of the 510(k) Context:

The K990708 510(k) Summary indicates that the Titanium Versalok Screw Assembly was found substantially equivalent to the predicate Versalok Screw Assembly. The core of this submission, related to demonstrating performance, was the provision of "Mechanical test data."

In 510(k) reviews for non-diagnostic devices like implants, the "acceptance criteria" are generally derived from:

• Performance of the predicate device: The new device must perform as safely and effectively as the predicate, often demonstrated through comparable mechanical properties.
• Recognized consensus standards: Adherence to national and international standards for material properties, mechanical integrity, and biocompatibility (e.g., ASTM, ISO).

The "study" to prove the device meets these criteria would be a series of benchtop mechanical tests (e.g., fatigue testing, static load testing, pull-out strength) and material characterization tests, comparing the results to the predicate device and relevant standards. The provided document heavily implies that this comparative mechanical testing was the basis for the substantial equivalence determination.

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