(95 days)
The ROSA® Knee System, for use with the ROSA® RECON Platform, is indicated as a stereotaxic instrumentation system for total knee replacement (TKA) surgery. It is to assist the surgeon in providing software-defined spatial boundaries for orientation and reference information to identifiable anatomical structures for the accurate placement of knee implant components.
The robotic arm placement is performed relative to anatomical landmarks as recorded using the system intraoperatively, and based on a surgical plan optionally determined pre-operatively using compatible X-ray or MRI based surgical planning tools.
It includes a robotic arm, an optical tracking system and accessories, software system, surgical instruments and accessories.
The ROSA Knee System is designed for use on skeletally mature patient population. The targeted population has the same characteristics as the population that is suitable for the implants compatible with the ROSA Knee System.
The ROSA Knee System is to be used with the following fixed bearing knee replacement systems in accordance with their indications and contraindications: NexGen® CR, NexGen CR-Flex Gender, NexGen LPS, NexGen LPS-Flex, NexGen LPS-Flex Gender, Persona® CR, Persona Ti-Nidium® CR, Persona Ti-Nidium PS, Persona IQ®, Vanguard® CR, and Vanguard PS.
The ROSA® Knee System for use with the ROSA RECON Platform is used to assist surgeons in performing Total Knee Arthroplasty (TKA) with features to assist with the bone resections as well as assessing the state of the soft tissues to facilitate implant positioning intra-operatively.
The ROSA® Knee System uses a Non-Device Medical Device Data System (Non-Device MDDS) called the Zimmer Biomet Drive Portal, which manages the creation and tracking of surgical cases. The cases reside on the portal until they are uploaded to the ROSA® RECON Platform before surgeries.
If the case is image-based, a 3D virtual bone model is generated pre-operatively by the PSI systems (X-PSI Knee System or CAS PSI Knee System) to create a 3D model of the patient's femur/tibia and allows for the preparation of a pre-operative surgical plan. An imageless option is also available where landmarks taken intra-operatively on the patient's bony anatomy are used to create the surgical plan. Accuracy of resections, knee state evaluation, and soft tissue assessment are the same between image-based and imageless options as they are always based on intraoperative landmarks.
The intraoperative workflow and surgical concepts implemented in the system remain close to the conventional TKA workflow. As such, at the time of the surgery, the system mainly assists the surgeon in (1) determining reference alignment axes in relation to anatomical landmarks, (2) planning the orthopedic implants location based on these reference alignment axes and orthopedic implant geometry (planning optionally based on a preoperative plan using pre-operative imaging), and (3) precisely positioning the cut guide relative to the planned orthopedic implant location by using a robotic arm.
The ROSA® Knee System is a stereotaxic instrumentation system designed to assist surgeons in Total Knee Arthroplasty (TKA) surgery.
Here's a breakdown of the acceptance criteria and study information based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Metric/Aspect | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Functional Equivalence | The device should assist the surgeon in providing software-defined spatial boundaries for orientation and reference information to identifiable anatomical structures for accurate knee implant components. | The ROSA® Knee System assists the surgeon in (1) determining reference alignment axes in relation to anatomical landmarks, (2) planning orthopedic implant location based on these reference alignment axes and implant geometry, and (3) precisely positioning the cut guide relative to the planned implant location using a robotic arm. |
| Accuracy of Resections | Not explicitly stated, but implied to be sufficient for TKA procedures and equivalent to the predicate. | Accuracy of resections is stated to be the same between image-based and imageless options, as they are always based on intraoperative landmarks. The system is designed to facilitate accurate placement of knee implant components. |
| Knee State Evaluation | Not explicitly stated, but implied to be sufficient for TKA procedures and equivalent to the predicate. | Knee state evaluation is stated to be the same between image-based and imageless options. |
| Soft Tissue Assessment | Not explicitly stated, but implied to be sufficient for TKA procedures and equivalent to the predicate. | Soft tissue assessment is stated to be the same between image-based and imageless options. The system also assists in joint balancing techniques. |
| Software Safety | The software contained in the device should not raise new issues of safety and effectiveness and should comply with FDA Guidance for the Content Premarket Submissions for Software Contained in Medical Devices and IEC 62304. | Software tests were conducted to satisfy requirements of the FDA Guidance and IEC 62304. The software was considered a "major" level of concern. The testing demonstrates that the ROSA Knee System does not raise any new issues of safety and effectiveness as compared to the predicate device(s). |
| Substantial Equivalence | The device should be at least as safe and effective as the legally marketed predicate device, with any differences not raising new questions of safety and effectiveness. | The proposed device and predicate device have the same intended use and similar indications for use, utilize the same platform components, and share similar technological characteristics. Differences in the software application and new instrumentation do not raise new questions of safety and effectiveness, and the proposed device is at least as safe and effective. |
| Physical/Performance | Not explicitly stated, but implied as ensuring the performance of implemented features and verifying related design inputs. | Physical/Performance Tests were conducted to ensure the performance of the implemented features and verify related design inputs. |
| Usability | Not explicitly stated, but implied as ensuring user interactions with the system are acceptable. | Usability Engineering addressed user interactions with the ROSA Knee System. |
| Performance in Simulated Use | The performance of the system should be acceptable under full simulated use on cadaveric specimens and equivalent to the predicate. | A Validation Lab-performed study validated that using the ROSA Knee System is equivalent to the predicate and that the performances of the system are acceptable under full simulated use on cadaveric specimens. |
2. Sample Size Used for the Test Set and Data Provenance
The document mentions "Validation Lab-performed to validate that using ROSA Knee System is equivalent to the predicate and that the performances of the system are acceptable under full simulated use on cadaveric specimens." However, it does not specify the sample size (number of cadaveric specimens or any other "test set").
The data provenance is described as being generated from "cadaveric specimens," suggesting a controlled laboratory setting. The country of origin of the data is not specified. It is a prospective study as testing was performed on the device.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of those Experts
The document does not specify the number of experts used or their qualifications for establishing ground truth in the "Validation Lab" studies or any other testing. Surgical planning can optionally be determined pre-operatively using compatible X-ray or MRI based surgical planning tools, but how this planning forms a "ground truth" and who defines it is not detailed.
4. Adjudication Method for the Test Set
The document does not describe any specific adjudication method (e.g., 2+1, 3+1, none) for the test set.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
The document does not mention a Multi-Reader Multi-Case (MRMC) comparative effectiveness study, nor does it quantify any effect size of human readers improving with AI vs. without AI assistance. The focus is on the device's performance in assisting the surgeon, not on human-reader performance with or without the device.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
The document does not explicitly state if a standalone algorithm-only performance study was conducted. The description of the device's function and the "Validation Lab" studies imply the device is used "with the ROSA® RECON Platform" and "assists the surgeon," indicating a human-in-the-loop context. However, the software verification and validation testing would assess the algorithm's performance in isolation to some extent.
7. Type of Ground Truth Used
The ground truth for the "Validation Lab" studies appears to be based on:
- Intraoperative Landmarks: Accuracy of resections, knee state evaluation, and soft-tissue assessment are "always based on intraoperative landmarks."
- Surgical Plan: The system assists in precise positioning "relative to the planned orthopedic implant location." This plan can be optionally determined pre-operatively using X-ray or MRI-based surgical planning tools.
- Equivalence to Predicate: The validation also aimed to prove that the system is "equivalent to the predicate," implying the predicate's established performance as a benchmark for ground truth.
8. Sample Size for the Training Set
The document does not provide any information regarding the sample size used for the training set for the software or any AI/machine learning components.
9. How the Ground Truth for the Training Set Was Established
The document does not describe how the ground truth for any potential training set was established. Given the nature of the device (stereotaxic instrument for TKA), if machine learning is involved, ground truth for training would likely come from well-annotated anatomical landmarks, surgical plans, and intraoperative measurements from historical TKA cases. However, this is not mentioned in the provided text.
§ 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).