(230 days)
The Synthes Arch™ Fixation System is intended for use in the lower cervical and upper thoracic spine (C3-T3) after a laminoplasty has been performed. The Arch™ Fixation System holds or buttresses the allograft in place in order to prevent the allograft from expulsion or impinging on the spinal cord.
The Synthes AFS is comprised of various sized, pre-bent mini-plates that are designed to fit the anatomy of the vertebral arch (i.e., between the pedicle and spinous process). The plates have screw holes located at the center and both ends of the plate to allow for attachment to the bone. The center hole in the plate is used for attachment to bone allograft. The plates are composed of commercially pure titanium which conforms to ASTM F67.
The screws intended for use with the mini-plates are available in a variety of lengths and diameter and are designed to match the anatomical requirements. The screws are composed of titanium alloy, Ti6Al7Nb, which conforms to ASTM F1295.
The Synthes AFS is designed to be used in conjunction with the components that comprise previously cleared Synthes posterior cervical spine products.
This premarket notification describes a spinal fixation system, not an AI/ML device. Therefore, the typical acceptance criteria and study designs relevant to AI/ML devices (e.g., performance metrics like sensitivity/specificity, human-in-the-loop studies, ground truth establishment) are not applicable here.
The document provided, K032534 for the Synthes Arch™ Fixation System (AFS), is a 510(k) submission for a medical device that uses conventional materials and mechanical principles. The criteria for its acceptance are based on a demonstration of "substantial equivalence" to existing legally marketed predicate devices, rather than performance against a set of statistical metrics derived from AI/ML output.
Here's an analysis of the provided text in the context of device acceptance:
1. A table of acceptance criteria and the reported device performance:
Since this is not an AI/ML device, the acceptance criteria are not in the form of numerical performance metrics like sensitivity or AUC. Instead, the acceptance criteria are implicitly that the device is substantially equivalent to predicate devices in:
| Acceptance Criteria Category | Reported Device Performance (Synthes AFS) |
|---|---|
| Intended Use | - Indicated for use in the lower cervical and upper thoracic spine (C3-T3) after laminoplasty. |
- Holds or buttresses allograft in place to prevent expulsion or impingement on the spinal cord.
- Claimed to be "substantially equivalent to information presented on the predicate device" for its use as a buttress plate. |
| Device Description/Design | - Comprised of various sized, pre-bent mini-plates designed to fit vertebral arch anatomy. - Plates have screw holes for attachment to bone and bone allograft.
- Used in conjunction with previously cleared Synthes posterior cervical spine products.
- Claimed to be "similar in design" to currently marketed orthopedic implants. |
| Material | - Plates: Commercially pure titanium (ASTM F67). - Screws: Titanium alloy, Ti6Al7Nb (ASTM F1295).
- All components consistent with ASTM standards.
- Claimed to be "similar in material" to currently marketed orthopedic implants. |
| Performance Characteristics | - Performance characteristics comparing the Synthes AFS to commercially available devices were provided to support a determination of substantial equivalence. - Claimed to be "similar in... performance" to currently marketed orthopedic implants. The exact performance metrics for mechanical or biological function are not detailed in this summary but would have been part of the full 510(k) submission (e.g., mechanical testing data, biocompatibility reports). |
2. Sample size used for the test set and the data provenance:
- Not applicable (N/A): This is a mechanical device, not an AI/ML system that uses test sets of data for algorithm evaluation. Instead, evidence for substantial equivalence typically relies on engineering analysis, mechanical testing (e.g., fatigue, static strength), and biocompatibility testing. The document does not provide details on the specific number of units tested, but such tests would have followed established ASTM or ISO standards for medical devices. The provenance would be from laboratory testing.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- N/A: Ground truth established by expert consensus is relevant for diagnostic or image-based AI/ML devices. For a mechanical fixation system, the "ground truth" is defined by established engineering and medical standards for device function (e.g., strength, biocompatibility) and clinical outcomes that would have been evaluated in the predicate device's history.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- N/A: Adjudication methods are used in studies involving human interpretation or expert review of data (e.g., images for diagnostic AI). For a mechanical device, performance is evaluated through objective physical and chemical tests, not subjective interpretation.
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:
- N/A: MRMC studies are specific to evaluating the impact of AI on human reader performance, which is not relevant for this type of mechanical spinal fixation system.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- N/A: This refers to standalone AI algorithm performance. No such algorithm is part of the Synthes AFS.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- N/A (in the AI/ML sense): For this device, the "ground truth" for demonstrating safety and effectiveness is based on:
- Established engineering principles and material standards: Adherence to ASTM F67 (commercially pure titanium) and ASTM F1295 (titanium alloy Ti6Al7Nb) ensures the materials meet recognized safety and performance standards.
- Mechanical testing: Though not detailed here, such devices undergo tests to confirm their structural integrity, fatigue life, and other mechanical properties under physiological loads. These tests provide objective data that serve as a form of "ground truth" for mechanical function.
- Clinical history of predicate devices: The primary argument for "substantial equivalence" is that the AFS is similar enough to previously cleared devices (e.g., bone plates, cerclage) that their known safety and effectiveness profiles can be extrapolated to the new device. The "ground truth" here is the clinical outcomes and safety profiles established for these predicate devices over time.
8. The sample size for the training set:
- N/A: This device does not involve a training set as it is not an AI/ML product.
9. How the ground truth for the training set was established:
- N/A: Not applicable for a mechanical medical device.
§ 888.3050 Spinal interlaminal fixation orthosis.
(a)
Identification. A spinal interlaminal fixation orthosis is a device intended to be implanted made of an alloy, such as stainless steel, that consists of various hooks and a posteriorly placed compression or distraction rod. The device is implanted, usually across three adjacent vertebrae, to straighten and immobilize the spine to allow bone grafts to unite and fuse the vertebrae together. The device is used primarily in the treatment of scoliosis (a lateral curvature of the spine), but it also may be used in the treatment of fracture or dislocation of the spine, grades 3 and 4 of spondylolisthesis (a dislocation of the spinal column), and lower back syndrome.(b)
Classification. Class II.