(85 days)
The Navio system is intended to assist the surgeon in providing software-defined spatial boundaries for orientation and reference information to anatomical structures during orthopedic procedures.
The Navio system is indicated for use in surgical knee procedures, in which the use of stereotactic surgery may be appropriate, and where reference to rigid anatomical bony structures can be determined. These procedures include unicondylar knee replacement (UKR), patellofemoral arthroplasty (PFA), and total knee arthroplasty (TKA),
The Navio system is indicated for use with cemented implants only.
The NAVIO system is a computer-assisted orthopedic surgical navigation and surgical burring system. The system uses established technologies of navigation, via a passive infrared tracking camera, to aid the surgeon in establishing a bone surface model for the target surgery and in planning the surgical implant location, based on intraoperativelydefined bone landmarks and known geometry of the surgical implant. The NAVIO system then aids the surgeon in executing the surgical plan by using a standard off-theshelf surgical drill motor and bur (Anspach eMax2 Plus System, cleared via K080802), which has been adapted using a tracking system.
The surgical bur is inserted into a handpiece, which allows the bur to move within the handpiece. The NAVIO system software controls the cutting engagement of the surgical bur based on its proximity to the planned target surface. The cutting control is achieved in two ways:
- Exposure control adjusts the bur's exposure with respect to a guard. If the surgeon encroaches on a portion of bone that is not to be cut, the NAVIO system retracts the bur inside the guard, disabling cutting.
- . Speed control regulates the signal going to the drill motor controller itself and will limit the speed of the drill if the target surface is approached. This mode of operation is useful in shaping surfaces of the condyle as well as placing post holes and fixation features for femoral and tibial cut guides.
Additionally, the surgeon can disable both controls and operate the NAVIO system handpiece as a standard navigated surgical drill. The surgeon must press on a footpedal to activate the surgical bur and enable cutting in all modes.
The provided document is a 510(k) premarket notification for the "Navio" surgical system, focusing on updates to its Total Knee Arthroplasty (TKA) software and support for additional implants. This document details non-clinical testing performed to establish substantial equivalence to a predicate device, rather than a standalone clinical study to prove novel device performance.
Therefore, the information regarding acceptance criteria and a study proving those criteria are met is derived from the non-clinical (bench) testing described in the submission, which aimed to demonstrate that the updated device is as safe and effective as its predicate.
Here's the breakdown of the information based on the provided text:
Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state quantitative acceptance criteria in a dedicated table. However, the conclusion section implies the key acceptance criterion is that the total knee implant placement accuracy using the new "Bur All" method of bone removal is "acceptable and similar" to the implant placement accuracy required for unicondylar and patellofemoral implant placement. It also states that the placement accuracy using the TKA cut guides (including the new Tibia Twin Peg cut guides) is "acceptable and similar" to previous submissions.
The "reported device performance" is qualitative and states that these criteria were met.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Total knee implant placement accuracy using the "Bur All" method is acceptable and similar to UKR and PFA implant placement accuracy. | "The accuracy verification testing performed indicates that the total knee implant placement accuracy using Bur All method of bone removal is acceptable and similar to the implant placement accuracy required for unicondylar and patellofemoral implant placement." (K170360, Page 10) |
| Placement accuracy using the NAVIO TKA cut guides (including new Tibia Twin Peg cut guides) is acceptable and similar to previous 510(k) submissions. | "Additionally, placement of the LEGION CR/PS and GENESIS II CR/PS Total Knee Implant systems using the NAVIO TKA cut guides (including the new Tibia Twin Peg cut guides) is acceptable and similar to the placement accuracy presented in the previous 510(k)." (K170360, Page 10) |
| Surgeon users are able to perform a TKA procedure in a simulated OR environment safely and effectively using the NAVIO system with TKA application. | "Usability validation testing demonstrated that surgeon users were able to perform a TKA procedure on cadaver in a simulated operating room environment safely and effectively using the NAVIO system with TKA application." (K170360, Page 10) and "Usability testing validated that surgeon users were able to perform a TKA procedure on cadaver in a simulated operating room environment safely and effectively using the NAVIO system with TKA application." (K170360, Page 9) |
Analysis of the Study and Ground Truth Establishment
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Sample size used for the test set and the data provenance:
- Test Set Sample Size: "Simulated knees (sawbones)" and "cadaver laboratory testing" were used. The exact number of simulated knees or cadavers is not specified in the provided document.
- Data Provenance: The testing was non-clinical, conducted in a laboratory setting. No country of origin for the cadavers or sawbones is specified, nor is whether the data is retrospective or prospective, as it's a bench test.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- "Trained surgeons and technical support personnel" performed the verification accuracy testing and usability testing.
- The number of surgeons/personnel is not specified.
- Their specific qualifications (e.g., years of experience) are not detailed beyond "trained surgeons and technical support personnel."
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Adjudication method for the test set:
- The document does not describe an adjudication method for establishing ground truth or evaluating the results of the non-clinical tests. This is typically more relevant for studies involving human interpretation or subjective measurements.
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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:
- No MRMC comparative effectiveness study was done. The document explicitly states: "No human clinical testing was conducted to determine safety and effectiveness of the NAVIO system." (K170360, Page 10). The study described is a non-clinical bench test confirming the performance of the device itself and its updated features.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- The primary evaluation described is a "human-in-the-loop" test, as "Trained surgeons and technical support personnel performed verification accuracy testing using simulated knees (sawbones) and cadaver laboratory testing." The device is intended to assist a surgeon. The accuracy testing evaluated the system's ability to achieve "acceptable" implant placement when operated by a surgeon.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Given the nature of the device (a surgical navigation and burring system) and the non-clinical testing, the ground truth for "accuracy" would likely be based on engineering measurements or predefined geometric targets. This means comparing the actual bone removal or implant placement (as measured by precision instruments on sawbones/cadavers) against the software-defined surgical plan/target. The "acceptable and similar" criteria suggest a comparison to known accurate outcomes for previous versions or similar surgical methods.
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The sample size for the training set:
- The document does not mention a training set sample size. This submission is for updates to an existing system ("enhancements to the NAVIO system TKA software"), suggesting the core algorithms were likely developed and "trained" (if machine learning was involved, which is not indicated for this specific system update in the document) previously. The current submission focuses on verifying the impact of software enhancements and new implant support through non-clinical testing.
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How the ground truth for the training set was established:
- As no training set is discussed, the method for establishing its ground truth is not provided. The system uses "established technologies of navigation... to aid the surgeon in establishing a bone surface model... and in planning the surgical implant location, based on intraoperatively-defined bone landmarks and known geometry of the surgical implant." This suggests a reliance on precise geometric modeling and established anatomical landmarks rather than a machine learning model requiring a traditional "training set" with ground truth labels in the typical sense.
§ 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).