(17 days)
The Vertefix® Pedicle Screw Spinal System is intended for posterior, non cervical pedicle fixation in skeletally mature patients receiving fusion by autogenous bone graft in the thoracolumbar spine for the following indications: Spondylolisthesis, Trauma (e.g.fracture or dislocation), Spinal stenosis, deformities or curvatures (scoliosis, kyphosis or lordosis), tumor, pseudoarthrosis, and failed previous fusion.
Removal of the implants after the attainment of a solid fusion is optional.
The Vertefix® Pedicle Screw Spinal System is a multiple component, posterior spinal fixation system which consists of pedicle screws, rods, set screws, connectors, hooks, and a transverse (cross) linking mechanism.
The Vertefix® Pedicle Screw Spinal System will allow surgeons to build a spinal implant construct to stabilize and promote spinal fusion. The Vertefix® Pedicle Screw Spinal System components are supplied non-sterile, and are single use.
This document describes a 510(k) premarket notification for the Vertefix® Pedicle Screw Spinal System, seeking to demonstrate substantial equivalence to a predicate device. As such, the study design focuses on comparative performance against the predicate rather than establishing novel acceptance criteria and reporting performance for an AI-powered device.
Therefore, many of the typical questions for AI acceptance criteria and studies (like sample sizes for test/training sets, expert ground truth, MRMC studies, standalone performance, etc.) are not applicable to this type of submission.
Here's an attempt to address the relevant points based on the provided text, and explicitly state when information is not available or not applicable:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance | Comments |
|---|---|---|---|
| Mechanical Performance | Substantial Equivalence to Predicate Device for Construct Testing (ASTM F1717) | "This testing demonstrated substantial equivalence to the predicate systems and other marketed systems." | Original Vertefix system met this. For the modified system (5.5mm rod), specific testing was not repeated because the change was expected to improve performance, but thread pullout testing was performed. |
| Material Properties | Conformance to ASTM F136 for Titanium alloy (Ti-6Al-4V ELI) | "The Vertefix® Spinal System components are fabricated from Titanium alloy (Ti-6Al-4V ELI) that conforms to ASTM F136." | This ensures material safety and performance. |
| Design and Function | Substantial Equivalence to Predicate Device in terms of intended use, operating principle, and design. | "Further comparison to the predicates also demonstrated substantial equivalence in terms of intended use, operating principle, materials, shelf life and design." | Confirms fundamental similarity to existing, approved devices. |
| Thread Design Strength | Adequate pullout strength (no specific numerical criteria given) | "Thread pullout testing was however performed to prove the thread design." | This was done for the modified system with the 5.5mm rod. |
| Safety and Effectiveness | No significant differences that would adversely affect product use compared to predicate. | "There are no significant differences between the Vertefix® Pedicle Screw Spinal System and the approved Vertefix® Pedicle Screw Spinal System or other spinal fixation systems currently being marketed, which would adversely affect the use of the product." | This is the overarching criterion for 510(k) substantial equivalence. |
2. Sample size used for the test set and the data provenance
- Not Applicable / Not Provided. This is a mechanical device, not an AI/software device that uses "data" in the typical sense for a test set. The "testing" referred to is mechanical testing of physical components (e.g., construct testing per ASTM F1717, thread pullout testing). The sample size for these mechanical tests is not specified in the provided text.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not Applicable. Ground truth in the context of an AI device typically refers to clinical diagnosis or outcome verified by experts. For a mechanical implant device, the "ground truth" is defined by established engineering standards (like ASTM F1717) and successful performance in those tests. Expert consensus for clinical diagnosis is not relevant here.
4. Adjudication method for the test set
- Not Applicable. Adjudication methods are relevant for subjective interpretations of data, particularly in clinical assessments where multiple readers might disagree. For mechanical testing against objective standards, adjudication is not a standard practice.
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
- Not Applicable. This is a mechanical spinal implant system, not a diagnostic or prognostic AI tool that would assist human readers.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not Applicable. This is a mechanical device. There is no 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 conformance to recognized industry standards (e.g., ASTM F1717) for mechanical testing and the material specifications (ASTM F136). The equivalence to a predicate device, which has already established safety and efficacy through its own testing and clinical use, serves as the primary benchmark.
8. The sample size for the training set
- Not Applicable / Not Provided. As a mechanical device, there is no "training set" in the computational sense. The design and testing are based on engineering principles and performance standards, not machine learning.
9. How the ground truth for the training set was established
- Not Applicable. There is no training set for this type of device.
Summary of the Study that Proves the Device Meets Acceptance Criteria:
The study that proves the Vertefix® Pedicle Screw Spinal System meets its acceptance criteria is primarily a bench-top mechanical evaluation demonstrating substantial equivalence to a legally marketed predicate device.
- Original System Testing: The original Vertefix® Pedicle Screw Spinal System underwent construct testing according to ASTM F1717. This testing demonstrated "substantial equivalence to the predicate systems and other marketed systems" in terms of mechanical performance.
- Material Conformance: The components are fabricated from Titanium alloy (Ti-6Al-4V ELI) conforming to ASTM F136, which establishes material quality and safety.
- Modified System Justification: For the modified system (with a 5.5mm rod), a full re-test against ASTM F1717 was not performed. The rationale provided was that this change was expected to "perform slightly better than the already tested Vertefix Spinal System." However, thread pullout testing was performed specifically to "prove the thread design" of the modified system.
- Comparative Analysis: A comparative analysis against various predicates (including the original Vertefix system) was performed, concluding that there are "no significant differences... which would adversely affect the use of the product" in terms of design, function, materials, operational principles, and intended use.
In essence, the "study" for this 510(k) submission is a combination of prior mechanical testing, material standardization, and a reasoned argument supported by specific additional testing (thread pullout) and comparative analysis to demonstrate that the new device is as safe and effective as a legally marketed predicate.
§ 888.3070 Thoracolumbosacral pedicle screw system.
(a)
Identification. (1) Rigid pedicle screw systems are comprised of multiple components, made from a variety of materials that allow the surgeon to build an implant system to fit the patient's anatomical and physiological requirements. Such a spinal implant assembly consists of a combination of screws, longitudinal members (e.g., plates, rods including dual diameter rods, plate/rod combinations), transverse or cross connectors, and interconnection mechanisms (e.g., rod-to-rod connectors, offset connectors).(2) Semi-rigid systems are defined as systems that contain one or more of the following features (including but not limited to): Non-uniform longitudinal elements, or features that allow more motion or flexibility compared to rigid systems.
(b)
Classification. (1) Class II (special controls), when intended to provide immobilization and stabilization of spinal segments in skeletally mature patients as an adjunct to fusion in the treatment of the following acute and chronic instabilities or deformities of the thoracic, lumbar, and sacral spine: severe spondylolisthesis (grades 3 and 4) of the L5-S1 vertebra; degenerative spondylolisthesis with objective evidence of neurologic impairment; fracture; dislocation; scoliosis; kyphosis; spinal tumor; and failed previous fusion (pseudarthrosis). These pedicle screw spinal systems must comply with the following special controls:(i) Compliance with material standards;
(ii) Compliance with mechanical testing standards;
(iii) Compliance with biocompatibility standards; and
(iv) Labeling that contains these two statements in addition to other appropriate labeling information:
“Warning: The safety and effectiveness of pedicle screw spinal systems have been established only for spinal conditions with significant mechanical instability or deformity requiring fusion with instrumentation. These conditions are significant mechanical instability or deformity of the thoracic, lumbar, and sacral spine secondary to severe spondylolisthesis (grades 3 and 4) of the L5-S1 vertebra, degenerative spondylolisthesis with objective evidence of neurologic impairment, fracture, dislocation, scoliosis, kyphosis, spinal tumor, and failed previous fusion (pseudarthrosis). The safety and effectiveness of these devices for any other conditions are unknown.”
“Precaution: The implantation of pedicle screw spinal systems should be performed only by experienced spinal surgeons with specific training in the use of this pedicle screw spinal system because this is a technically demanding procedure presenting a risk of serious injury to the patient.”
(2) Class II (special controls), when a rigid pedicle screw system is intended to provide immobilization and stabilization of spinal segments in the thoracic, lumbar, and sacral spine as an adjunct to fusion in the treatment of degenerative disc disease and spondylolisthesis other than either severe spondylolisthesis (grades 3 and 4) at L5-S1 or degenerative spondylolisthesis with objective evidence of neurologic impairment. These pedicle screw systems must comply with the following special controls:
(i) The design characteristics of the device, including engineering schematics, must ensure that the geometry and material composition are consistent with the intended use.
(ii) Non-clinical performance testing must demonstrate the mechanical function and durability of the implant.
(iii) Device components must be demonstrated to be biocompatible.
(iv) Validation testing must demonstrate the cleanliness and sterility of, or the ability to clean and sterilize, the device components and device-specific instruments.
(v) Labeling must include the following:
(A) A clear description of the technological features of the device including identification of device materials and the principles of device operation;
(B) Intended use and indications for use, including levels of fixation;
(C) Identification of magnetic resonance (MR) compatibility status;
(D) Cleaning and sterilization instructions for devices and instruments that are provided non-sterile to the end user; and
(E) Detailed instructions of each surgical step, including device removal.
(3) Class II (special controls), when a semi-rigid system is intended to provide immobilization and stabilization of spinal segments in the thoracic, lumbar, and sacral spine as an adjunct to fusion for any indication. In addition to complying with the special controls in paragraphs (b)(2)(i) through (v) of this section, these pedicle screw systems must comply with the following special controls:
(i) Demonstration that clinical performance characteristics of the device support the intended use of the product, including assessment of fusion compared to a clinically acceptable fusion rate.
(ii) Semi-rigid systems marketed prior to the effective date of this reclassification must submit an amendment to their previously cleared premarket notification (510(k)) demonstrating compliance with the special controls in paragraphs (b)(2)(i) through (v) and paragraph (b)(3)(i) of this section.