(285 days)
The GII spinal fixation system when used as a pedicle screw system in the non-cervical posterior spine, the GII spinal fixation system is to be used in skeletally mature patients as an adjunct to fusion using autograft and/or allograft for one or more of the following:
(1) Degenerative or severe spondylolisthesis (Grades 3 and 4) of the fifth lumbar/first sacral (L5-S1) joint with objective evidence of neurologic impairment,
(2) Fracture,
(3) Dislocation,
(4) Scoliosis,
(5) Kyphosis,
(6) Spinal tumor, and/or
(7) Failed previous fusion (pseudoarthrosis).
The GII spinal fixation system when used as a hook and sacral/iliac screw fixation system in the non-cervical posterior spine, the GII spinal fixation system is to be used in skeletally mature patients as an adjunct to fusion using autograft and/or allograft for one or more of the following:
(1) Degenerative spondylolisthesis with objective evidence of neurologic impairment,
(2) Fracture,
(3) Dislocation,
(4) Scoliosis,
(5) Kyphosis,
(7) Spinal tumor, and/or
(8) Failed previous fusion (pseudoarthrosis).
The new GII-Ti-Poly-Axial Screw is intended to be used with the existing components, nuts, washers, cross-links and instrumentation as currently provided with the cleared GII Spinal Fixation System. The previously cleared indications for use of the GII Spinal Fixation System are unchanged.
Acceptance Criteria and Device Performance Study for GII-Ti-Poly-Axial Screw
This document describes the acceptance criteria and the study that proves the GII-Ti-Poly-Axial Screw meets these criteria, based on the provided 510(k) summary.
1. Table of Acceptance Criteria and Reported Device Performance
| Criteria | Acceptance Standard | Reported Device Performance |
|---|---|---|
| Mechanical Performance (Equivalence) | Equivalent to existing screw components of the cleared GII Spinal Fixation System (K980852, K032604, K051089) | "Test results demonstrate that the new GII-Ti-Poly-Axial Screw performs in a manner equivalent to the existing screw components of the cleared GII Spinal Fixation System." |
| Design Equivalence | Comparable design to predicate devices | "Equivalence can be seen in the comparable design..." |
| Material Composition Equivalence | Comparable material composition to predicate devices | "...material composition..." |
| Surgical Technique Equivalence | Comparable surgical technique to predicate devices | "...surgical technique..." |
| Intended Use Equivalence | Comparable intended use to predicate devices | "...intended use..." |
| Testing Characteristics Equivalence | Comparable testing characteristics to predicate devices | "...and testing characteristics of the GII system and other currently marketed spinal systems." |
2. Sample Size Used for the Test Set and Data Provenance
The document states, "Samples were tested according to accepted engineering and scientific principals." However, it does not provide specific details on:
- The exact sample size used for the mechanical testing of the GII-Ti-Poly-Axial Screw.
- The data provenance (e.g., country of origin, retrospective or prospective nature). Given the nature of a mechanical device test, it is highly likely that the testing was performed in a laboratory setting, likely in Switzerland or at a contract testing facility, and therefore prospective in nature.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of those Experts
For a mechanical device like a spinal screw, "ground truth" in the context of clinical outcomes or expert consensus on images is not directly applicable. The "ground truth" here is established by engineering standards and validated testing methodologies to confirm mechanical equivalence. The document does not specify the number or qualifications of experts involved in defining these engineering standards or conducting the tests. It broadly states, "Testing is complete. Samples were tested according to accepted engineering and scientific principals."
4. Adjudication Method for the Test Set
Adjudication methods like 2+1 or 3+1 are relevant for studies involving human interpretation (e.g., image reading). Since this study involves mechanical testing of a device's performance against established engineering standards, an adjudication method is not applicable in the traditional sense. The equivalence is demonstrated through objective mechanical measurements and data analysis.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
A Multi-Reader Multi-Case (MRMC) comparative effectiveness study is designed to assess the impact of a device or AI on human reader performance, typically in diagnostic imaging. This type of study was not performed for the GII-Ti-Poly-Axial Screw, as it is a mechanical implant and not an imaging or diagnostic AI device. Therefore, there is no effect size for human reader improvement with or without AI assistance.
6. Standalone Performance Study (Algorithm Only)
A standalone performance study (algorithm only) is relevant for AI/software devices. Since the GII-Ti-Poly-Axial Screw is a physical medical implant, a standalone performance study is not applicable in this context. Its "performance" is demonstrated through physical and mechanical testing, not algorithmic output.
7. Type of Ground Truth Used
The ground truth used for this device is based on established engineering standards and validated mechanical testing protocols. The performance of the new GII-Ti-Poly-Axial Screw is compared directly against the performance characteristics of previously cleared predicate devices (K980852, K032604, K051089) within the GII Spinal Fixation System. This includes characteristics like design, material composition, and mechanical properties determined through testing.
8. Sample Size for the Training Set
For a mechanical device undergoing performance testing for substantial equivalence, a "training set" as understood in machine learning is not applicable. The device is not learning from data; its physical properties are being tested. If "training set" were to broadly refer to the predicate devices and their established performance data that serve as a benchmark, the document references several existing screw components from the GII Spinal Fixation System (K980852, K032604, K051089). The specific number of individual units of these predicate devices used to establish their performance is not provided in this summary.
9. How Ground Truth for the Training Set Was Established
Again, a "training set" in the AI sense does not apply here. However, if we interpret "ground truth for the training set" as the established performance baseline of the predicate devices, this baseline was established through:
- Prior mechanical testing of the predicate devices according to accepted engineering and scientific principles.
- Regulatory clearance (e.g., via previous 510(k) submissions K980852, K032604, and K051089) which confirmed their safety and effectiveness based on their design, materials, and performance data at the time of their clearance.
- Adherence to recognized standards relevant to spinal implants (though specific standards are not cited in this summary).
§ 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.