(29 days)
The NuVasive® ACP System is intended for anterior screw fixation of the cervical spine C2-C7 for the following indications: degenerative disc disease (as defined by neck pain of discogenic origin with degeneration of the disc confirmed by patient history and radiographic studies), trauma (including fractures), tumors, deformity (defined as kyphosis, lordosis, or scoliosis), pseudarthrosis, failed previous fusion, spondylolisthesis, and spinal stenosis.
The NuVasive ACP System is an anterior cervical plating system that consists of a variety of implant components including screws and plates, as well as associated manual general surgical instruments. The implants are available in a variety of different shapes and sizes to suit the individual pathology and anatomical conditions of the patient. The subject device components are manufactured from titanium alloy (Ti-6Al-4V ELI) conforming to ASTM F136 or ISO 5832-3. The NuVasive ACP System was initially cleared in K191500, and lower static torsion test values were presented in K201078. The purpose of this submission is to introduce design changes to the ACP Self-Drilling Screws. Select changes implemented via the add to file process as well as additional design updates are also presented in this submission.
Here's an analysis of the provided FDA 510(k) summary, specifically focusing on the acceptance criteria and the study that proves the device meets those criteria:
Device: NuVasive® ACP System (Anterior Cervical Plating System)
The provided document describes a spinal intervertebral body fixation orthosis and the review for its 510(k) premarket notification. This type of device is a physical implant, not an AI/ML-based diagnostic or assistive device. Therefore, the questions related to AI/ML performance metrics, ground truth, expert adjudication, and comparative effectiveness studies are not applicable to this submission.
The "acceptance criteria" for such a device are primarily based on demonstrating substantial equivalence to a predicate device through non-clinical performance data (e.g., mechanical testing).
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implied by regulation and predicate comparison) | Reported Device Performance |
|---|---|
| Meet or exceed performance of predicate device (mechanical strength, specifically static torsion). | "The results of these studies show that the subject NuVasive ACP System meets or exceeds the performance of the predicate device and does not introduce any new risks" |
| Conform to relevant ASTM standards (e.g., ASTM F1717 for static torsion). | "Static torsion testing per ASTM F1717" |
| Biocompatibility of materials. | "The subject device components are manufactured from titanium alloy (Ti-6Al-4V ELI) conforming to ASTM F136 or ISO 5832-3." |
| Maintain the same technological characteristics as predicate. | "The subject device was shown to be substantially equivalent and have the same technological characteristics to its predicate devices through comparison in areas including design, intended use, material composition, function, and range of sizes." |
2. Sample size used for the test set and the data provenance
- Test Set Sample Size: Not explicitly stated as "sample size" in the context of clinical studies. The testing performed is non-clinical (mechanical testing). The document does not specify the number of implants or test specimens used for the static torsion testing.
- Data Provenance: The data is generated from laboratory mechanical testing. The country of origin and whether it's retrospective or prospective are not applicable as it's not human subject data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- This is not applicable. Ground truth, in the context of clinical interpretation by experts, is not relevant for this type of mechanical device submission. The "ground truth" for mechanical performance is established by standardized testing methods and material specifications (e.g., ASTM F1717 for static torsion, ASTM F136 for material).
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
- This is not applicable. Adjudication methods are used for expert consensus on clinical data. For mechanical testing, the results are quantitative and objective, typically requiring no adjudication.
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 is not applicable. This device is a physical implant, not an AI-assisted diagnostic or therapeutic system.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- This is not applicable. This device is a physical implant, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- The "ground truth" for this device's performance is established by objective, standardized mechanical testing results (e.g., torque at failure, deformation under load) compared against predetermined criteria derived from predicate device performance and relevant ASTM standards.
8. The sample size for the training set
- This is not applicable. This is a physical device, not an AI/ML algorithm that requires a training set.
9. How the ground truth for the training set was established
- This is not applicable. This is a physical device, not an AI/ML algorithm.
Summary of the Study Proving Acceptance Criteria:
The study proving the device meets the acceptance criteria is a non-clinical performance study focused on mechanical testing.
- Purpose: To demonstrate that the NuVasive® ACP System is substantially equivalent to predicate devices, particularly regarding its mechanical performance and material composition.
- Key Test: Static torsion testing per ASTM F1717.
- Material Testing: The device components are manufactured from titanium alloy (Ti-6Al-4V ELI) conforming to ASTM F136 or ISO 5832-3, ensuring material properties meet established standards.
- Results/Conclusion: "The results of these studies show that the subject NuVasive ACP System meets or exceeds the performance of the predicate device and does not introduce any new risks." This statement confirms that the device's mechanical performance, specifically in static torsion, was found to be acceptable and comparable or superior to the legally marketed predicate devices, thereby establishing substantial equivalence.
§ 888.3060 Spinal intervertebral body fixation orthosis.
(a)
Identification. A spinal intervertebral body fixation orthosis is a device intended to be implanted made of titanium. It consists of various vertebral plates that are punched into each of a series of vertebral bodies. An eye-type screw is inserted in a hole in the center of each of the plates. A braided cable is threaded through each eye-type screw. The cable is tightened with a tension device and it is fastened or crimped at each eye-type screw. The device is used to apply force to a series of vertebrae to correct “sway back,” scoliosis (lateral curvature of the spine), or other conditions.(b)
Classification. Class II.