(298 days)
The Waypoint GPS™ is indicated for use during pedicle screw pilot hole drilling to provide visual feedback to the surgeon of changes in color to the tissue at the tip of the probe that may indicate contact with soft tissues and possible vertebral cortex perforation. The Waypoint GPS™ is indicated for use in both open and percutaneous (MIS) procedures.
The Waypoint GPS™ is comprised of a single use, disposable device and a software application that is downloaded onto the provided tablet. The system is intended to surgeons during pilot hole drilling for pedicle screw placement. Waypoint GPS™ probe is single use disposable and consists of a handle containing electronics and a stainless-steel shaft with distal LED and fiber optics for visualizing the tissues immediately in contact with the distal end of the probe. The device produces visual signals to indicate changes in color associated with possible verforation. It uses light to provide visual alerts to indicate a change in anatomical structure to prevent placement in soft tissues or vertebral cortex perforation.
The Waypoint Guided Pedicle System (GPS) is indicated for use during pedicle screw pilot hole drilling to provide visual feedback to the surgeon of changes in color to the tissue at the tip of the probe that may indicate contact with soft tissues and possible vertebral cortex perforation.
Here's an analysis of the acceptance criteria and the study results:
1. Table of Acceptance Criteria and Reported Device Performance
Although explicit "acceptance criteria" values (e.g., minimum accuracy percentage) are not provided in a single, clear table within the document, we can infer the criteria from the "Test Method Summary" and "Results" columns, especially for the GLP Animal Study which directly compares performance.
| Acceptance Criteria (Inferred) | Reported Device Performance |
|---|---|
| Biocompatibility: Device materials are non-cytotoxic, non-sensitizing, non-irritating, non-toxic, and non-pyrogenic. | Passed. Non-cytotoxic, non-sensitizing, non-irritating, non-toxic, non-pyrogenic. |
| Insertion Force: Device can complete a minimum of 15 insertions into Sawbones at a specified depth without mechanical failure. | Passed. Each shaft was able to successfully complete 15x insertions without mechanical failure. |
| Torque on the shaft (endurance): Device can withstand 15x torque cycles on the shaft without mechanical failure while inserted in Sawbones. | Passed. Each shaft was able to successfully withstand 15x torque on a shaft cycle without mechanical failure. |
| Torque to failure: Device shaft can withstand a target torque without failure. | Passed. Each shaft was able to successfully withstand the target torque. |
| Simulated Use Testing: Device can successfully complete pairing with tablet, color calibration, color testing, and battery monitoring after endurance testing. Users can perform procedure and interpret results. | Passed. Each device successfully completed all procedure steps. Users can perform the device procedure and correctly interpret the device output. |
| Visualization and Color: Device output (RGB values and color change) reliably reflects contact with different colored materials. | Passed. Each device successfully completed the test cycle and displayed correct colors and RGB values. |
| Electrical Safety and EMC: Device complies with IEC 60601-1 and IEC 60601-1-2 standards. | Passed. |
| Software Verification and Validation: Software complies with FDA guidance for medical device software (moderate level of concern). | Passed. |
| Sterilization Validation: Sterilization process achieves sterility. | Passed. |
| Distribution and Aging: Device maintains performance (insertion force, torque, simulated use, visualization, color) after climactic conditioning, accelerated aging, and package performance testing. Sterile barrier is maintained. | Passed. Performance tests were successful on both unaged and aged devices. Sterile barrier was maintained. |
| GLP Animal Study (Non-Inferiority): The subject device (Waypoint GPS System) is non-inferior to the predicate PediGuard device in correctly identifying tip location (cortical bone, cancellous bone, breach). Users can adequately interpret results. | Passed. Users correctly identified GPS device tip location in 100% of procedures. Users successfully distinguished between cortical bone, cancellous bone, and a breach by the change in color and RGB values. Users correctly identified PediGuard tip location in 95% of procedures. Demonstrated with statistical significance (0.050) that the subject device is non-inferior to the predicate. |
2. Sample Size Used for the Test Set and the Data Provenance
- GLP Animal Study: The study involved multiple users performing pilot hole procedures in ovine lumbar vertebrae. The exact number of individual procedures or specific animal count is not given, but it states "The total number GPS procedures (including transverse processes) demonstrated the device performs as intended and users adequately interpret results with 95/95." This implies a total of 95 GPS procedures were evaluated.
- Provenance: This was an in vivo animal study using ovine (sheep) lumbar vertebrae. The geographical origin of the animals or the study site is not explicitly stated. It is a prospective study design for the animal study component.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
- GLP Animal Study: "Fluoroscopic CT was used to verify pilot hole depth, GPS, and PediGuard results." This indicates that imaging (Fluoroscopic CT) served as the primary, objective ground truth. It is not explicitly stated how many experts (e.g., radiologists) interpreted these CT scans or their qualifications. However, in such studies, interpretation of CT by qualified personnel (likely veterinarians or radiologists with expertise in animal anatomy) would be standard.
- Cadaver Study: The document mentions "a cadaver," implying human cadavers were used for a portion of the simulated use testing. Again, the number and qualifications of experts establishing ground truth (likely anatomical dissection for confirmation) are not specified.
4. Adjudication Method for the Test Set
- GLP Animal Study: The primary ground truth was established by Fluoroscopic CT. The interpretation of this CT data (which would inherently involve expert adjudication if there were ambiguities, though not explicitly detailed) served as the objective measure. The device's output (color description for GPS, auditory for PediGuard) was then compared against this objective ground truth. It doesn't describe a specific adjudication method like "2+1" for human reader discrepancies, as the ground truth was derived from imaging.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- Yes, a comparative study was done for the GLP Animal Study. It was a side-by-side comparison of the Waypoint GPS device and the predicate PediGuard device involving "multiple users" (readers).
- Effect Size of Human Readers' Improvement with AI vs. without AI Assistance: This specific metric (improvement of human readers with AI assistance) is not directly provided or applicable in the requested format.
- The study compares two devices: Waypoint GPS (subject device) which provides visual feedback (color changes) and PediGuard (predicate device) which provides auditory feedback (change in cadence and pitch). Both are "assistance" devices.
- The study aims to show non-inferiority of the GPS device to the PediGuard device, not necessarily the improvement of human readers with either device compared to without any device.
- However, the results show:
- Users correctly identified GPS device tip location in 100% of procedures.
- Users correctly identified PediGuard tip location in 95% of procedures.
- This demonstrates that with the assistance of the GPS device, users were able to correctly identify tip location more consistently (100%) than with the predicate PediGuard device (95%) in the animal model. The study concludes statistical non-inferiority (p=0.050).
6. Standalone (i.e., algorithm only without human-in-the-loop performance) Study
- No, a standalone study was not performed or described. The Waypoint GPS device is designed to provide "visual feedback to the surgeon" and its performance is evaluated in the context of "user interpretation" of its outputs. The "human-in-the-loop" is an integral part of its intended use and evaluation.
7. Type of Ground Truth Used
- GLP Animal Study: Fluoroscopic CT scans were used to objectively verify pilot hole depth and location, establishing the ground truth for bone anatomy and breach detection.
- Cadaver Study: Likely anatomical dissection or expert visualization for the human cadaver component, though not explicitly detailed.
8. Sample Size for the Training Set
- Not Applicable / Not Provided. The document describes a medical device, not an AI/ML algorithm that undergoes a distinct training phase with a specific dataset. The "device" in this context refers to the physical instrument and its integrated electronics/software, which are likely designed and calibrated based on engineering principles and preclinical testing, rather than "training" on a dataset like a machine learning model.
9. How the Ground Truth for the Training Set Was Established
- Not Applicable / Not Provided. As explained above, there isn't a "training set" in the common AI/ML sense for this device. The principles of operation (spectral reflectance for color changes) are built into the device design rather than learned from labeled data.
§ 874.1820 Surgical nerve stimulator/locator.
(a)
Identification. A surgical nerve stimulator/locator is a device that is intended to provide electrical stimulation to the body to locate and identify nerves and to test their excitability.(b)
Classification. Class II.