(167 days)
The Precision Screw is intended for establishing fixed reference point(s) in patients undergoing Stereotactic Surgery for procedures in the cortical bone of the vertebrae. The Precision Screw can be used as an accessory with frameless navigation systems.
The Precision Screw is a self-drilling metallic fixation device used only as a reference point during stereotactic procedures. Commonly known as a Fiducial Screw or a stereotaxic instrument, the Precision Screw can be used as an accessory with frameless navigation systems, as appropriate, from other manufacturers.
The provided document pertains to the 510(k) premarket notification for the "Precision Screw" device and focuses on establishing substantial equivalence to a predicate device rather than presenting a study with specific acceptance criteria and detailed performance data in the typical sense of a clinical or standalone AI performance study.
Therefore, many of the requested sections (e.g., sample size for test set, number of experts for ground truth, MRMC study, training set details) are not applicable or cannot be extracted directly from this type of regulatory submission. The document emphasizes non-clinical testing for safety and technological equivalence.
Here's an attempt to answer the questions based only on the provided text, noting where information is not available:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state "acceptance criteria" in a quantitative, pass/fail table format. Instead, it refers to fulfilling standards and demonstrating equivalence to a predicate device. The performance is reported in terms of meeting these standards and being "highly visible and fit for the purpose."
| Acceptance Criteria Category (Implied) | Reported Device Performance |
|---|---|
| Biocompatibility | Conforms to FDA Blue Book Memorandum #G95-1 and ISO 10993-1. Titanium material conforms to ASTM F136. |
| Mechanical Strength & Integrity | Meets performance standards identified in ASTM F543-13 and ISO 6475:1989 for torsional properties and driving torque. |
| Visual Acuity/Visibility (Frameless Navigation) | Screws are "highly visible and fit for the purpose they are intended for in the operative setting" when inserted into a Spinal Bone Model and assessed with O-Arm images. |
| Sterilization | Sterilization has been validated. |
| Anatomic Location Safety | Viable anatomic locations on the vertebrae were evaluated for safety and identified in the labeling. |
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 for any of the non-clinical tests mentioned. For the "Visual Acuity" test, it mentions "inserting Precision Screws into a Spinal Bone Model" but does not give a number of screws or models used.
- Data Provenance: Not explicitly stated. The submitter is Cryptych Pty Ltd. based in Australia. The testing standards (ASTM, ISO) are international. The location of the testing laboratories is not provided. The data is non-clinical (bench testing), not 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. The tests performed are non-clinical (biocompatibility, mechanical strength, visibility on imaging models) and do not involve expert consensus on diagnoses or interpretations of patient data. For the "Visual Acuity" test, no mention of expert readers or their qualifications is provided; it states "The visibility of the Precision Screw on O-Arm images... was assessed."
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. This type of adjudication method is used in clinical studies involving multiple human readers for diagnostic tasks, which is not what was performed.
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, an MRMC comparative effectiveness study was not done. This device is a physical medical device (a screw for navigation), not an AI-powered diagnostic or assistive tool. The document states: "clinical testing was not required to support substantial equivalence."
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 device is a physical screw.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The concept of "ground truth" (in the sense of a gold standard for a diagnostic algorithm) is not directly applicable to the non-clinical tests conducted for this physical device. Instead, the "truth" is established by:
- Adherence to recognized international standards (e.g., ASTM F136 for material, ASTM F543-13 and ISO 6475:1989 for mechanical properties, ISO 10993 for biocompatibility).
- Validation against expected performance for a physical device (e.g., "Sterilization has been validated," "Screws are highly visible and fit for the purpose").
8. The sample size for the training set
Not applicable. This device is a physical medical device, not an AI or machine learning algorithm that requires a training set.
9. How the ground truth for the training set was established
Not applicable, as there is no training set for a physical device.
§ 882.4560 Stereotaxic instrument.
(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).