(268 days)
The Karma® Fixation System is intended for bilateral facet stabilization for fusion as an adjunct to a 1-level interbody lumbar fusion from L1 to L5 with autogenous and/or allogenic bone graft. The Karma Fixation System must be accompanied by an FDA cleared intervertebral body fusion device implanted at the same spinal level. The Karma Fixation System is indicated for the treatment of patients with lumbar degenerative disc disease at a single level from L1 to L5 in skeletally mature patients who have failed conservative care.
The Karma® Fixation System is a system that provides adjunctive fixation. The system consists of a PEEK band. The Karma band consists of a strap manufactured from PEEK compounded with 7.5% barium sulphate for radiopacity. The leading tip of the device is comprised of a spherical feature followed by a tapered neck to allow for an instrument to assist in advancing the strap around the bony structures to be secured. The spherical tip of the device contains a tantalum insert for visualization when fluoroscopic imaging is used. The device has teeth along its length that interact with a latching mechanism at the opposite end of the strap. The latch allows a loop created by feeding the strap through the latch to be made consecutively shorter or taut by continuing to pull the strap through the latch. Prior to creating the loop, the spherical tip of the device is cut off and discarded to allow for the strap to pass through the latch. The latch resists the lengthening of the loop due to forces that would pull the strap in the opposite direction, thereby securing the bony structures. Once the desired loop length is reached, the unneeded portion of the strap may be cut off and discarded. An instrument, Tensioner, is provided and can be used fully tension the implant.
The provided FDA 510(k) clearance letter and summary for the Karma® Fixation System is for a medical device (spinal fixation system), not a software device or AI-powered system that would typically have acceptance criteria focused on algorithm performance metrics like sensitivity, specificity, or AUC. Therefore, the questions related to AI performance, such as sample size for test sets, expert adjudication, MRMC studies, standalone performance, and training set details, are not applicable to this submission.
The "acceptance criteria" for a medical device like the Karma® Fixation System are typically related to:
- Mechanical and Biomechanical Performance: Ensuring the device can withstand expected physiological loads and perform its intended structural function.
- Biocompatibility: Verifying that the materials used are safe for implantation in the human body.
- Sterilization: Confirming the device can be effectively sterilized.
- Labeling and Packaging: Ensuring proper information is provided.
- Substantial Equivalence: Demonstrating that the device is as safe and effective as a legally marketed predicate device.
The study that proves the device meets its acceptance criteria (i.e., its safety and effectiveness compared to a predicate) is discussed under "Performance Data" and "Clinical Data."
Here's an interpretation based on the information provided, addressing the applicable points:
1. Table of Acceptance Criteria and Reported Device Performance
Since this is a 510(k) submission for a spinal fixation system, the "acceptance criteria" are implied by the need to demonstrate substantial equivalence to a predicate device in terms of safety and effectiveness. The "reported device performance" refers to the studies conducted to support this equivalence. Specific numerical acceptance criteria (e.g., minimum load-bearing capacity, fatigue life) are often part of the detailed testing protocols submitted to the FDA but are not explicitly listed in this summary.
| Acceptance Criteria (Implied for Substantial Equivalence) | Reported Device Performance (Summary) |
|---|---|
| Biomechanical Stability | Demonstrated through biomechanical cadaveric testing. |
| Durability/Fatigue Life | Demonstrated through Finite Element Analysis (FEA). |
| Material Compatibility/Wear | Demonstrated through cadaveric abrasion testing. |
| Functional Equivalence | Usability studies conducted to evaluate operating principle. |
| Clinical Safety and Effectiveness | Evaluated using CT evaluations at 12 and 24 months, adverse event data, and patient-reported outcomes (ODI, VAS for back/leg pain). |
| Design, Material, Manufacturing Equivalence | Claimed to be identical to the reference device (K180728 / K190289). |
2. Sample Size Used for the Test Set and the Data Provenance
- Sample Size for Test Set:
- Biomechanical studies: Not specified, but typically involves a small number of cadaveric spines.
- Clinical Data: Not specified, but includes CT evaluations, adverse event data, and patient-reported outcomes at 12 and 24 months. The specific number of patients is not mentioned.
- Data Provenance: Not explicitly stated (e.g., country of origin). The nature of the clinical data (CT evaluations, adverse events, patient-reported outcomes at specific follow-up points) suggests a prospective or retrospective clinical study, but this is not definitively stated.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This question is not applicable to this type of device submission. The "ground truth" for a spinal fixation system is typically established through objective measurements in mechanical/biomechanical testing and clinical outcomes, rather than expert consensus on image interpretation. Clinical assessments would be performed by qualified medical professionals (e.g., surgeons, radiologists), but their specific number or qualifications for "ground truth establishment" are not relevant in the context of AI model evaluation.
4. Adjudication Method for the Test Set
This question is not applicable as it pertains to expert disagreement resolution in AI model evaluation, which is not relevant for musculoskeletal implants.
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
This question is not applicable. MRMC studies are specific to evaluating AI-assisted diagnostic or interpretative devices, not spinal fixation systems.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
This question is not applicable. The Karma® Fixation System is a physical implant, not a standalone algorithm.
7. The Type of Ground Truth Used
The "ground truth" for this device's performance assessment relies on a combination of:
- Biomechanical Data: Objective measurements from cadaveric testing (e.g., stability, stiffness).
- Computational Modeling: Results from Finite Element Analysis (FEA) predicting stress distribution and fatigue.
- Clinical Outcomes Data:
- Imaging: CT evaluations at 12 and 24 months.
- Adverse Event Data: Reported complications.
- Patient-Reported Outcomes (PROs): Oswestry Disability Index (ODI) and visual analog scale (VAS) for back and leg pain.
8. The Sample Size for the Training Set
This question is not applicable. The Karma® Fixation System is a physical medical device, not an AI model that requires a "training set."
9. How the Ground Truth for the Training Set Was Established
This question is not applicable. There is no "training set" for this type of device.
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