(55 days)
The iMNS Medacta Navigation System is intended to be used to support the surgeon during specific orthopedic surgical procedures by providing information on bone resections, instrument and implant positioning during joint replacement.
The iMNS Medacta Navigation System provides computer assistance to the surgeon based on anatomical landmarks and other specific data obtained intra-operatively that are used to place surgical instruments.
Examples of some surgical procedures include but are not limited to: Total Knee Replacement Minimally Invasive Total Knee Replacement
The iMNS Medacta Navigation System is a device for computer aided navigation of surgical instruments used in total knee replacement surgery. The system works on the common principle of stereotaxic technology in which passive markers are securely mounted on the patient's bones and an infrared camera is used to monitor the spatial location of those markers. This information is used to locate the anatomical landmarks such as centers of rotation of the femur head, knee and ankle intraoperatively. These measurements are displayed on a computer screen in real time. The instruments are then outfitted with the passive markers to improve the positioning of the cutting guides. The information from the system with the "navigated" instruments assists the surgeon in conducting the bone resections and positioning of the orthopedic surgical implants. The surgeon maintains control of the surgery and makes any decisions required with regard to bone resections and implant positioning but the iMNS Medacta Navigation System provides real time support and information throughout the surgery.
The iMNS Medacta Navigation System consists of the following kev components:
- · An acquisition system composed of two infrared cameras equipped . with infrared light emitting diodes (LED) to track the position of the passive markers.
- . A computer running the proprietary Medacta software and a monitor,
- . Interface devices of a keyboard, foot pedal and optional mouse to control the system, and
- Manual reusable surgical instruments. .
The software application called GMK v4.2.2 is designed to work with Medacta's GMK Total Knee System, cleared under K090988. The manual reusable surgical instruments include instruments specifically designed for navigated surgery and other standard surgical instruments needed to conduct total knee replacement.
The Medacta iMNS Navigation System (GMK v4.2.2) is a computer-aided navigation system for total knee replacement surgery. The device was tested through a series of "design verification and validation" protocols with predefined acceptance criteria. These tests were conducted as part of the Special 510(k) submission (K100314) to demonstrate substantial equivalence to its predicate device (iMNS Medacta Navigation System v4.0, K083872).
Here's a breakdown of the requested information based on the provided text:
1. A table of acceptance criteria and the reported device performance
The document states that "The iMNS Medacta Navigation System was tested as part of design verification and validation to written protocols with pre-defined acceptance criteria. The testing met all acceptance criteria." However, specific numerical acceptance criteria (e.g., accuracy thresholds) and their corresponding reported device performance values are not detailed in the provided text. The tables list the Protocol IDs, Report IDs, and Titles of the verification and validation activities.
| Protocol ID | Report ID | Title | Acceptance Criteria (Not Detailed) | Reported Device Performance (Not Detailed) |
|---|---|---|---|---|
| IL 07.09.026 | EG08 and Annex 1 | GUI Verification | Met | Met |
| EG13 and Annex 1 | GUI Verification | Met | Met | |
| IL 07.09.028 | EG09 | Validation of resections planning and cutting blocks positioning | Met | Met |
| EG11 | Validation of resections planning and cutting blocks positioning | Met | Met | |
| IL 07.09.029 | EG12 | Single Point/ Multi Point/ Directional Acquisition's Validation | Met | Met |
| IL 07.09.048 | EG10 | Functionality of the Navigation Software in Deep Stress Cases | Met | Met |
| IL07.09.026 | GMK00 | GUI Verification | Met | Met |
| IL07.09.027 | GMK06 | Mechanical axis and saggital plane reconstruction | Met | Met |
| IL07.09.028 | GMK02 | Resection planning & cutting block positioning | Met | Met |
| IL07.09.029 | GMK03 | Single point/multipoint directional acquisition | Met | Met |
| IL07.09.030 | GMK05 | Single point acquisition | Met | Met |
| IL07.09.031 | GMK01 | Geometry of knee implants & ancillaries | Met | Met |
| IL07.09.092 | GMK04 | Validation of HW & SW compatibility & relative stability | Met | Met |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document primarily describes internal design verification and validation activities. It mentions "Design validation was conducted on the iMNS Medacta Navigation System in a simulated user setting by a surgeon". It does not specify a sample size for a test set (e.g., number of patients or cases), nor does it provide information on data provenance (country of origin, retrospective/prospective). The testing appears to be conducted in a simulated environment rather than on patient data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
The design validation was conducted "by a surgeon". The specific number of surgeons, their qualifications, or how they established "ground truth" (e.g., in a simulated environment for measurement accuracy) is not detailed beyond the mention of "a surgeon."
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
The document does not describe any adjudication method for the test set results. The validation was conducted by "a surgeon," implying a single expert evaluation for the simulated user setting.
5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
A Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not conducted or reported in this document. The device is a surgical navigation system, not an AI diagnostic tool for human readers. It assists the surgeon directly in instrument positioning.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
The document implies that "standalone" testing (algorithm only performance) was inherently part of the design verification and validation activities, particularly for functionalities related to "res resection planning," "single point acquisition," and "mechanical axis and sagittal plane reconstruction." These would evaluate the accuracy and functionality of the software's calculations and measurements independent of the surgeon's real-time input, though the text does not explicitly use the term "standalone performance." The "simulated user setting" test with a surgeon would combine both algorithm and human-in-the-loop.
7. The type of ground truth used (expert concensus, pathology, outcomes data, etc)
Given the nature of the device (surgical navigation), the "ground truth" for the verification and validation activities likely involved predefined geometric or anatomical targets and measurements within the simulated environment. For example, for "resection planning," the system's output for bone cuts would be compared against the ideal planned cuts. For "mechanical axis and sagittal plane reconstruction," the system's computed axes would be compared against known or calculated true axes. The document does not explicitly state the type of ground truth in terms such as "expert consensus," "pathology," or "outcomes data."
8. The sample size for the training set
The document does not mention a training set or its sample size. This type of 510(k) submission generally focuses on design verification and validation of a defined software version, not on the developmental process involving a training set for machine learning. The system's core principle is "stereotaxic technology," implying pre-programmed algorithms rather than machine learning models requiring training data.
9. How the ground truth for the training set was established
Since a training set is not mentioned, there is no information on how its ground truth would have been 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).