(29 days)
The Navitrack™ System - Total Hip Replacement CT-Free is indicated for use as a stereotaxic instrument to assist in the positioning of hip replacement components. It is a computer controlled image-guidance system equipped with a three-dimensional tracking sub-system. It is intended to assist in precisely positioning hip replacement components intra-operatively by displaying their positions relative to the joint's alignment axes as based on user-identified anatomical landmarks.
Identically as in the predicate, the Navitrack™ System – Total Hip Replacement CT-Free device consists of a software-driven workstation, an optical tracking system, surgical instruments, and tracking accessories, designed to assist the surgeon in the placement of Total Hip Replacement (THR) components. Tracking devices are incorporated with given surgical instruments, as well as on to fixation bases that attach to the pelvis, such to allow the ability to track and display to the user their respective positions intraoperatively. The pelvis is displayed to the user in the form of its main alignment axes. The alignment axes are determined and recorded intra-operatively by identifying the kev anatomical references that are used clinically to align and position the THR components. The instruments are schematically represented. The modifications to the predicate are to additionally track the femur and femoral instrumentation similarly as is done for the pelvis, in order to also assist in the placement of the THR components for the femur.
The Navitrack™ System – Total Hip Replacement CT-Free is a surgical navigation system that assists in the placement of Total Hip Replacement (THR) components.
Here's an analysis of its performance data based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance | Comments |
|---|---|---|---|
| Accuracy and Performance | Adequacy of depicting the positioning of femoral THR component for intended use. | Assessed to be "adequate for its intended use." | No specific quantitative metrics (e.g., error margins, precision) are provided for this system in the available text. The assessment refers to the femoral component, which is the new addition compared to the predicate. |
| Safety and Efficacy | No new safety and efficacy issues raised with modifications. | "Non-clinical tests were performed to assess that no new safety and efficacy issues were raised in the device." | General statement; no specific testing details or results are outlined. |
| Substantial Equivalence | Equivalence to predicate device (Navitrack System™ - Total Hip Replacement CT-Free Cup, K030827). | Determined to be "substantially equivalent" by the FDA. | The device is a modification of the predicate, extending its capabilities to the femur. The fundamental technology is unchanged. |
2. Sample Size Used for the Test Set and Data Provenance:
The document explicitly states that "Non-clinical tests were performed." It does not specify the sample size used for the test set or the data provenance (e.g., country of origin, retrospective/prospective). Given the nature of a non-clinical test for a surgical navigation system, it likely involved bench testing or cadaveric studies, rather than patient data.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
The document does not mention the use of experts to establish a ground truth for the test set. The "non-clinical tests" likely focused on technical performance and accuracy measurements rather than expert clinical assessment of outcomes.
4. Adjudication Method for the Test Set:
Not applicable, as no expert-based ground truth establishment is described.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
No mention of a multi-reader multi-case (MRMC) comparative effectiveness study. The document focuses on the technical performance and substantial equivalence to a predicate, not on a direct comparison of human reader performance with and without AI assistance.
6. Standalone Performance:
Yes, a standalone (algorithm only without human-in-the-loop performance) study was inferred from the "Non-clinical tests were performed to assess that no new safety and efficacy issues were raised in the device. They consisted in verifying that the accuracy and performance of the system in depicting the positioning of the femoral THR component was adequate for its intended use." This indicates the system's ability to accurately depict component positioning, which is an intrinsic function of the algorithm.
7. Type of Ground Truth Used:
The type of ground truth used for the non-clinical tests is not explicitly stated but can be inferred as technical or metrological ground truth. For a navigation system, this would typically involve:
- Precise physical measurements: Using highly accurate measurement tools (e.g., CMM, optical trackers, calibrated jigs) to determine the true position and orientation of components in a controlled environment.
- Geometric models: Comparing the system's output to known, precisely defined geometric models of the pelvic and femoral anatomy and the THR components.
It is not expert consensus, pathology, or outcomes data, as these are typically associated with clinical studies or diagnostic devices.
8. Sample Size for the Training Set:
The document does not provide any information about a training set size. This device describes a "software-driven workstation" and an "optical tracking system" that uses "user-identified anatomical landmarks" to determine alignment axes. This suggests a rule-based or model-based system, rather than a machine learning model that would typically require a distinct training set. The "software was correspondingly modified to handle the added capabilities" rather than "retrained."
9. How the Ground Truth for the Training Set Was Established:
Not applicable, as there is no mention of a traditional machine learning training set or associated ground truth establishment process. The "ground truth" for the system's functionality is likely embedded in the engineering design, calibration, and pre-defined algorithms for geometric calculations based on digitized landmarks.
§ 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).