(28 days)
The Navitrack® System -- OS Unicondylar Knee Universal is indicated for use as a stereotaxic instrument to assist in the positioning of unicondylar knee replacement components intra-operatively.
It is a computer controlled image-guidance system equipped with a three-dimensional tracking sub-system. It is intended to assist the surgeon in determining reference alignment axes in relation to anatomical landmarks, and in precisely positioning the alignment instruments relative to these axes by displaying their locations.
The Navitrack System - OS Unicondylar Knee Universal device consists of software, a computer workstation, an optical tracking system, surgical instruments, and tracking accessories, designed to assist the surgeon in the placement of unicondylar knee replacement components.
Tracking devices are incorporated with given surgical instruments, as well as on to fixation bases that attach to each of the femur and tibia, such to allow the ability to track and display to the user their respective positions intra-operatively. The femur and tibia are displayed to the user in the form of their main alignment axes. The alignment axes are determined and recorded intra-operatively by identifying the key anatomical references that are used clinically to align and position the components.
The Navitrack® System – OS Unicondylar Knee Universal is a stereotaxic instrument designed to assist in the positioning of unicondylar knee replacement components intra-operatively. It uses a computer-controlled image-guidance system with a 3D tracking sub-system to determine reference alignment axes and precisely position alignment instruments.
Here's an analysis of the provided information regarding acceptance criteria and the supporting study:
1. Table of Acceptance Criteria and Reported Device Performance
The provided document does not explicitly state numerical acceptance criteria. Instead, it makes a general claim regarding performance compared to a predicate device.
| Acceptance Criterium (Implied) | Reported Device Performance |
|---|---|
| Accuracy and performance adequacy for intended use | "accuracy and performance of the system was adequate for its intended use" |
| Performance not reduced compared to predicate (OS Knee Universal) | "not reduced in comparison to the OS Knee Universal predicate." |
| No new safety and efficacy issues | "no new safety and efficacy issues were raised in the device." |
2. Sample Size Used for the Test Set and Data Provenance
The document states "Non-clinical tests were performed" to assess accuracy and performance. However, it does not specify the sample size used for the test set or the data provenance (e.g., country of origin, retrospective or prospective).
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not provide information on the number of experts used to establish ground truth for the test set or their qualifications.
4. Adjudication Method for the Test Set
The document does not describe any adjudication method used for the test set.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size
The document does not mention a multi-reader multi-case (MRMC) comparative effectiveness study or any effect size related to human readers improving with or without AI assistance. The device is described as "assisting the surgeon," implying human involvement, but no formal comparative study with human readers is detailed.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
The document describes the device as providing "image guidance assistance" to the surgeon, indicating a human-in-the-loop system. It does not state whether a standalone (algorithm-only) performance evaluation was conducted.
7. The Type of Ground Truth Used
The document describes the performance assessment as "non-clinical tests" to verify accuracy and performance. Given the nature of a surgical navigation system, the "ground truth" for accuracy would likely involve:
- Physical measurements/phantoms: Using precise physical models or phantoms where the true anatomical landmarks and alignment axes are known and can be independently verified.
- Engineering specifications/tolerances: Comparing the device's measurements and guidance to pre-defined engineering tolerances for surgical accuracy.
However, the document does not explicitly state the specific type of ground truth used.
8. The Sample Size for the Training Set
The document does not provide any information regarding a training set or its sample size. Since this is a navigation system that digitizes anatomical landmarks and guides instrument placement, it's possible that a "training set" in the traditional machine learning sense might not be applicable or explicitly mentioned as it would be for an AI-diagnostic device. The system's core functionality relies on established anatomical referencing and geometric calculations, rather than a learning algorithm trained on a dataset of cases.
9. How the Ground Truth for the Training Set Was Established
As no training set is mentioned (see point 8), the document does not describe how ground truth for a training set was established.
§ 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).