(57 days)
The GII Spinal Fixation System using pedicle screws is intended for patients: (a) having severe spondylolisthesis (Grades 3 and 4) at the L5-S1 joint; (b) who are receiving fusions using autogenous bone graft only; (c) who are having the device fixed or attached to the lumbar and sacral spine; and (d) who are having the device removed after the development of a solid fusion mass. The levels of pedicle screw fixation may be from L3 to the sacrum.
The GII Spinal Fixation System is available in stainless steel and titanium alloy and includes plates, screws and optional spacers. Plates are offered in a variety of lengths (41.1 to 141.2mm) and have longitudinal openings to accommodate the mechanical thread portion of the screw. Screws are have both cancellous and mechanical threads, and are available with mechanical thread lengths of 27 or 12mm, cancellous thread lengths ranging from 37 to 52mm in 5mm increments and cancellous thread outer diameters ranging from 5.5 to 8.5mm. Optional spacers are available in 3 or 5mm heights or in a 1.5 to 5mm angled height.
The request is asking for details about the acceptance criteria and the study that proves a device, the GII Spinal Fixation System, meets those criteria, based on the provided 510(k) summary and FDA letter.
However, after reviewing the provided documents, it is clear that this submission pertains to a spinal fixation system (a mechanical device), not an AI/ML-driven medical device.
Therefore, many of the requested fields, such as "Multi-reader multi-case (MRMC) comparative effectiveness study," "standalone (algorithm only) performance," "sample size for the test set," "data provenance," "number of experts for ground truth," "adjudication method," "type of ground truth," "sample size for training set," and "how ground truth for training set was established," are not applicable to this type of device and are not addressed in the provided documents.
The primary evidence presented for this device's performance, as stated under "Performance Characteristics" in the 510(k) Summary, revolves around mechanical testing.
Here's a breakdown of what can be extracted:
Acceptance Criteria and Device Performance for GII Spinal Fixation System
| Criterion | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Intended Use | The device is intended for patients: | |
| (a) having severe spondylolisthesis (Grades 3 and 4) at the L5-S1 joint; | ||
| (b) who are receiving fusions using autogenous bone graft only; | ||
| (c) who are having the device fixed or attached to the lumbar and sacral spine; and | ||
| (d) who are having the device removed after the development of a solid fusion mass. | ||
| The levels of pedicle screw fixation may be from L3 to the sacrum. | The FDA determined the device is substantially equivalent for the exact same stated indications for use, confirming it meets the intended use criteria. The device system was found equivalent only to similar devices labeled and intended for these specific conditions. It explicitly states that the device is intended for "severe spondylolisthesis (Grades 3 and 4) of the fifth lumbar - first sacral (L5-S1) vertebral joint" and associated conditions. | |
| Material Composition | Components are manufactured from either stainless steel or titanium alloy. | The 510(k) Summary states: "The GII Spinal Fixation System components are manufactured from either stainless steel or titanium alloy." This aligns with the material specifications. |
| Design Specifications | Plates: Variety of lengths (41.1 to 141.2mm) with longitudinal openings. | |
| Screws: Both cancellous and mechanical threads. Mechanical thread lengths of 7 or 12mm. Cancellous thread lengths from 37 to 52mm in 5mm increments. Cancellous thread outer diameters from 5.5 to 8.5mm. | ||
| Optional Spacers: 3 or 5mm heights or 1.5 to 5mm angled height. | The 510(k) Summary describes the device with these exact specifications: "Plates are offered in a variety of lengths (41.1 to 141.2mm) and have longitudinal openings to accommodate the mechanical thread portion of the screw. Screws are have both cancellous and mechanical threads, and are available with mechanical thread lengths of 7 or 12mm, cancellous thread lengths ranging from 37 to 52mm in 5mm increments and cancellous thread outer diameters ranging from 5.5 to 8.5mm. Optional spacers are available in 3 or 5mm heights or in a 1.5 to 5mm angled height." | |
| Mechanical Performance | The device must demonstrate adequate static and fatigue mechanical properties to support its intended use in spinal fixation. (Specific quantitative acceptance criteria for static/fatigue strength, stiffness, etc., are not provided in these documents). | "Static and fatigue mechanical testing were supplied in support of the GII Spinal Fixation System 510(k) notification." The FDA's clearance implies that the provided mechanical testing data was sufficient to demonstrate substantial equivalence to predicate devices, thereby meeting the implicit performance expectations for such devices. |
| Substantial Equivalence | The device must be demonstrated to be substantially equivalent to other legally marketed predicate devices. | "The GII Spinal Fixation System was determined to be substantially equivalent to several commercially available systems." The FDA's 510(k) clearance letter explicitly states, "we have determined the device system is substantially equivalent...". |
Regarding the other requested information:
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Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective):
- Not applicable / Not provided. For mechanical testing, samples refer to the device components tested, not patient data. The documents do not specify the number of components tested for static and fatigue performance, nor their provenance.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience):
- Not applicable. Ground truth in the context of AI/ML or clinical studies is not relevant here. For mechanical testing, the "ground truth" is measured physical properties, typically against engineering standards or predicate device performance.
-
Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable. This refers to clinical or expert review processes, which are not detailed for mechanical testing.
-
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. This is a mechanical device, not an AI/ML diagnostic or assistive device.
-
If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- No. This is a mechanical device.
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The type of ground truth used (expert concensus, pathology, outcomes data, etc):
- Mechanical properties / Engineering standards. For a mechanical device, the ground truth for performance relates to physical measurements (e.g., load-bearing capacity, fatigue life) against established engineering standards or comparative data from predicate devices. The exact standards are not listed in these documents.
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The sample size for the training set:
- Not applicable. There is no "training set" for this type of device approval.
-
How the ground truth for the training set was established:
- Not applicable. There is no "training set."
§ 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.