(88 days)
Knee+ is a stereotaxic system including an intraoperative software as a medical device and surgical instruments. Knee+ is intended for primary Total Knee Replacement, to assist the surgeon in determining reference alignment axes in relation to anatomical landmarks, in order to position the cutting computed mechanical axis. The Knee+ includes smart glasses as a Head Mounted Device (HMD) for displaying information to the user intraoperatively. The smart glasses should not be relied upon solely and should always be used in conjunction with traditional methods.
Knee+ is a navigation system dedicated to orthopaedic knee surgery. It includes KneePlus software and KneeTools reusable surgical instruments.
The main purpose of Knee+ is to assist the surgeon during primary Total Knee Arthroplasty (TKA) interventions.
Knee+ provides information to help locate and orientate the main femoral and tibial cutting TKA. Knee+ allows the surgeon to adjust the orientation of the cutting plane orientation and the level of resection by collecting anatomical references during the TKA procedure using surgical instruments. The software locates in a 3D reference frame the instruments which include markers. All collected coordinates are treated by software algorithms to provide the surgeon with relevant orientation and location of the tracked cutting guide. Knee+ software is installed on a wearable Head Mounted Device (HMD) which includes a camera and displays intraonerative information to the user. A near-eye display allows the HMD screen or the field of view when needed.
Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria (Performance Measure) | Reported Device Performance |
|---|---|
| Repeatability (ASTM F2554) | Performs according to requirements and specifications. |
| Accuracy (ASTM F2554) | Performs according to requirements and specifications. |
| Cleaning and Sterilization Efficacy | Validated in accordance with AAMI TIR30, ISO 17665-1, ISO 1764, and FDA guidance. |
| Biocompatibility | Modified instruments still covered by ISO 10993 series testing. No new risks introduced by non-contacting materials. |
| Human Factors/Usability | Safe and effective for intended users, uses, and use environments (confirmed by observational data and participant understanding). |
| Software Verification & Validation | Compliant with IEC 62304 and FDA guidance. |
| Overall Safety and Effectiveness | As safe and effective as legally marketed predicate devices. |
2. Sample Size for the Test Set and Data Provenance:
The document mentions "Bench testing was conducted" to evaluate repeatability and accuracy according to ASTM F2554. However, it does not specify the sample size used for this test set nor the data provenance (e.g., country of origin, retrospective or prospective nature of data).
For human factors testing, it states "Test participants representing the intended in the human factor validation testing." Again, the exact number of participants (sample size) is not provided.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications:
The document does not explicitly state the number of experts used or their qualifications for establishing ground truth for any of the test sets.
4. Adjudication Method for the Test Set:
The document does not describe any specific adjudication method (e.g., 2+1, 3+1) for the test set.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done, and Effect Size:
The document does not indicate that a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was done. The device (Knee+) is described as assisting the surgeon, and the smart glasses "should not be relied upon solely and should always be used in conjunction with traditional methods," implying a human-in-the-loop scenario. However, no specific comparative study with and without AI assistance quantifying human reader improvement is mentioned.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done:
The document focuses on the device's performance within the surgical workflow as an assisting tool. While software verification and validation were performed, there is no explicit mention of a standalone algorithm-only performance study independent of human interaction or the "Head Mounted Device (HMD)." The emphasis is on the integrated system providing information to the user.
7. The Type of Ground Truth Used:
The document describes the ground truth in terms of:
- Engineering Specifications/Requirements: For repeatability and accuracy, the ground truth is defined by the device's ability to "perform according to its requirements and specifications" in accordance with ASTM F2554.
- Regulatory Standards/Guidance: For cleaning, sterilization, and biocompatibility, the ground truth is established by adherence to specific AAMI, ISO, and FDA guidance documents.
- User Understanding/Safety & Effectiveness: For human factors, the ground truth is based on "observational data" and "assessment of their understanding of essential information through the interview," confirming safety and effectiveness for intended users.
There is no mention of ground truth established through pathology or outcomes data.
8. The Sample Size for the Training Set:
The document does not provide any information regarding the sample size for the training set. This is likely because the submission focuses on the performance and safety of the updated device rather than the foundational machine learning model (if any) training.
9. How the Ground Truth for the Training Set Was Established:
As no training set is mentioned, there is no information provided on how its ground truth 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).