(166 days)
The Spinal Elements Posterior Cervical/Thoracic Spinal System is intended for posterior fixation of the cervical and thoracic spine (CI-T3) for the following conditions: degenerative disc disease (neck pain of discogenic origin with degeneration of the disc as confirmed by patient history and radiographic studies); spondylolisthesis; spinal stenosis; trauma (fracture/dislocation); failed previous fusion; tumors.
The use of polyaxial pedicle screws is limited to placement in T1-T3 for treating thoracic conditions only. The screws are not intended to be placed in the cervical spine.
The Spinal Elements Posterior Cervical/Thoracic System consists of a variety of fixation devices that are attached to the spine by means of screws and hooks placed in/or on the pedicles or posterior elements of the various vertebrae, rods that span the distance between the screws/hooks, and transverse connectors. Screws are intended for attachment to the thoracic (T1-T3) spine only. All components of the system are manufactured from titanium alloy (Ti-6A1-4V conforming to ASTM F 136 or ISO 5832-3). The system achieves fixation by the mechanical joining of the rods, screws, hooks, and connectors. A variety of constructs may be assembled to suit the individual pathology and anatomy of the patient.
Here's an analysis of the provided text regarding the acceptance criteria and study for the Spinal Elements Posterior Cervical/Thoracic Spinal System:
The provided text describes a medical device, its intended use, and the performance testing conducted. However, it does not contain information about a study proving the device meets acceptance criteria in the context of human performance (e.g., accuracy of a diagnostic AI product) or clinical outcomes. Instead, the document focuses on mechanical performance testing for a spinal implant system to demonstrate its substantial equivalence to predicate devices.
Therefore, many of the requested categories (e.g., AI performance, expert ground truth, sample sizes for training/test sets, MRMC studies) are not applicable to the information provided.
Let's break down what is available in the input:
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria Category | Specific Criteria (Implicit) | Reported Device Performance | Comments |
|---|---|---|---|
| Mechanical Performance | Ability to withstand static compression forces without failure. | All test results indicate the system will perform as intended. | Testing was performed according to ASTM F1717. |
| Ability to withstand dynamic compression forces without failure. | All test results indicate the system will perform as intended. | Testing was performed according to ASTM F1717. | |
| Ability to withstand torsion forces without failure. | All test results indicate the system will perform as intended. | Testing was performed according to ASTM F1717. | |
| Biocompatibility | Compatibility with biological tissue. (Implicit by use of ASTM F136 or ISO 5832-3 Ti-6Al-4V) | Device components are manufactured from titanium alloy (Ti-6A1-4V conforming to ASTM F 136 or ISO 5832-3). | The use of this specific titanium alloy is a standard for biocompatibility in implantable devices. |
Important Note: The document states "All test results indicate the system will perform as intended." This is a general statement. Specific numerical thresholds for "acceptance" (e.g., "withstanding X N of force") and the actual measured results are not provided in this summary. The "acceptance criteria" here are implied by the nature of the mechanical tests (i.e., the device should not fail under the tested conditions as defined by ASTM F1717).
The following sections are largely not applicable or cannot be fully answered based on the provided text, as the study described is a mechanical bench test, not a clinical or AI performance study.
2. Sample size used for the test set and the data provenance:
- Sample Size: Not specified for the mechanical tests. ASTM F1717 would define the number of samples required for each test type (static, dynamic, torsion).
- Data Provenance: The tests are "non-clinical, mechanical testing," implying benchtop lab testing rather than human or animal data. The location of the testing is not specified, but it's presumed to be in a controlled laboratory environment. It is not retrospective or prospective in the clinical sense.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not Applicable. Mechanical testing does not involve human experts establishing "ground truth" in the way a diagnostic AI study would. The "ground truth" is defined by the physical properties and performance requirements of the materials and design, tested against established standards (ASTM F1717).
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Not Applicable. Adjudication methods are relevant for subjective assessments, typically in clinical or image-based studies where different human readers might interpret data differently. Mechanical tests have objective outcomes (e.g., fracture, deformation, yield strength).
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 device, not an AI diagnostic tool.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Not Applicable. This is a mechanical device, not an AI algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- The "ground truth" for this device's performance is its ability to meet the mechanical performance standards defined by ASTM F1717 for spinal implant constructs. This is a physical/engineering standard, not a biological or clinical one (like pathology or outcomes data).
8. The sample size for the training set:
- Not Applicable. This is not an AI/machine learning device; there is no training set.
9. How the ground truth for the training set was established:
- Not Applicable. As there is no training set for an AI model, this question is not relevant.
Conclusion:
The K120467 document details the mechanical safety and performance of a spinal implant system through conformity to established ASTM standards. It does not involve AI, human reader studies, or complex ground truth establishment by medical experts for diagnostic accuracy. The "study" referenced is a series of in-vitro mechanical tests, and its "acceptance criteria" are implied by the successful performance of the device under these standardized conditions, demonstrating substantial equivalence to predicate devices.
§ 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.