(121 days)
The iASSIST™ Knee System is a computer assisted stereotaxic surgical instrument system to assist the surgeon in the positioning of orthopedic implant system components intra-operatively. It involves surgical instruments and position sensors to determine alignment axes in relation to anatomical landmarks and to precisely position alignment instruments and implant components relative to these axes.
Example orthopedic surgical procedures include but are not limited to: Total Knee Arthroplasty.
The iASSIST Knee System consists of tracking sensors, a computer system, software, and surgical instruments designed to assist the surgeon in the placement of Total Knee Replacement components.
The tracking sensors combined with the surgical instruments provide positional information to help orient and locate the main femoral and tibial cutting planes as required in knee replacement surgery. This includes means for the surgeon to determine and thereafter track each of the bones' alignment axes relative to which the cutting planes are set. The computer system and software components control and sequence the functions of the sensors per the applicable knee surgery steps via wireless communication.
Here's a breakdown of the acceptance criteria and the study details for the iASSIST™ Knee System, based on the provided text:
Acceptance Criteria and Device Performance
| Acceptance Criteria (Design Requirement) | Reported Device Performance |
|---|---|
| Overall Hip-Knee-Ankle alignments within ±3° of target in 90% of cases | "demonstrated satisfactory performance per the intended use including obtaining overall Hip-Knee-Ankle alignments within ±3° of target in 90% of the cases per design requirements." |
Study Details
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Sample size used for the test set and the data provenance:
- Sample Size: Not explicitly stated as a numerical count of cases, but implied within "multiple surgeons" performing "Full use simulations tests using cadaver specimens or sawbones."
- Data Provenance: The tests were "performed under simulated bench test conditions" and "using cadaver specimens or sawbones." This indicates prospective, simulated lab data, not retrospective human clinical data from a specific country of origin.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Number of Experts: "multiple surgeons"
- Qualifications of Experts: The text refers to "surgeons," implying they are qualified medical doctors specialized in orthopedic surgery, particularly Total Knee Arthroplasty. No further specific qualifications (e.g., years of experience) are provided.
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Adjudication method for the test set:
- The document does not explicitly describe an adjudication method (like 2+1, 3+1). The evaluation seems to be based on the system's ability to achieve the target alignment as measured by the surgeons during the simulation.
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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 is mentioned. The study described is a performance verification of the device itself under simulated conditions, not a comparison of human reader performance with and without AI assistance. The device assists the surgeon; it doesn't replace their interpretation or decision-making in a diagnostic sense.
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If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- The device is explicitly described as a "computer assisted stereotaxic surgical instrument system to assist the surgeon." It is designed for use with a human surgeon. Therefore, a standalone (algorithm only) performance assessment, disconnected from the surgeon's interaction, is not applicable or described in this context. The "Performance tests" assessed aspects like "calibration, femur registration, tibia registration, tibia navigation, femur navigation, and tibia & femur cut validation," which are components contributing to the assisted surgical process.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The ground truth for the "Overall Hip-Knee-Ankle alignments" was the target alignment (within ±3°). This target is a predefined surgical goal. The measurement of whether this target was met would likely be determined by reference instruments or techniques during the cadaver/sawbones simulations.
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The sample size for the training set:
- The document does not specify a training set sample size. The description of "Performance tests" and "Full use simulations" relates to testing and verification rather than training of algorithms.
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How the ground truth for the training set was established:
- Since no training set is explicitly mentioned or described, the method for establishing its ground truth is also not provided. The document focuses on the performance and verification of the system's software algorithms and overall function.
§ 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).