(127 days)
When used as a posterior, noncervical pedicle screw system, the VertiFlex™ Spinal Screw System is 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 of the thoracic, lumbar, and sacral spine:
- Degenerative disc disease (DDD) as defined by back pain of discogenic origin . with degeneration of the disc confirmed by patient history and radiographic studies;
- Severe spondylolisthesis (Grades 3 and 4) of the L5-S1 vertebra; .
- Degenerative spondylolisthesis; .
- Trauma (i.e., fracture or dislocation); .
- . Spinal stenosis;
- Deformities or curvatures (i.e., scoliosis, kyphosis, and/or lordosis); ●
- Tumor: .
- Pseudoarthrosis; and/or .
- Failed previous fusion. .
The VertiFlex™ Spinal Screw System is a posterior, non-cervical instrumentation system consisting of both pedicle screws and rigid connecting rods. Screws are of polyaxial or monoaxial (fixed) top-loading design, are composed of titanium alloy, and are available in a range of diameters and lengths to accommodate physiological requirements. The rods are composed of titanium, and are available in both straight and curved (pre-lordosed) styles, and in a range of lengths to accommodate both single-level and multiple levels procedures. The System may be implanted by either conventional surgical methods, or via minimally-invasive/percutaneous techniques. Manual instrumentation for implantation of the System is available for both conventional and minimally-invasive procedures. Screws, rods, and instruments are offered non-sterile.
The provided document is a 510(k) summary for a medical device called the "VertiFlex™ Spinal Screw System." It describes the device, its intended use, and substantial equivalence to predicate devices, but it does not contain acceptance criteria or a study proving the device meets those criteria, especially in the context of an AI/algorithm-based device as implied by your detailed questions.
This 510(k) pertains to a physical implantable device (pedicle screws) and its regulatory review for market clearance based on substantial equivalence to existing devices, not an AI or software as a medical device (SaMD). Therefore, many of your specific questions related to AI/algorithm performance metrics, training sets, expert ground truth, MRMC studies, and standalone performance are not applicable to the information contained in this document.
Here's an analysis based on the provided text, highlighting what is present and what is absent:
1. A table of acceptance criteria and the reported device performance
- Not Applicable / Not Provided. The document does not define specific performance acceptance criteria in terms of quantitative metrics for a device (like sensitivity, specificity, accuracy, etc.) nor does it report performance against such criteria. This is a physical implant device, and its performance is assessed via non-clinical tests (mechanical/material properties) and comparison to predicate devices, not AI performance metrics.
2. 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. No "test set" in the context of an algorithm's performance is mentioned. The document refers to "non-clinical tests" in accordance with standards like ASTM F1717-04 for spinal implant constructs in a vertebrectomy model. This implies mechanical testing of the physical device, not data analysis on a patient dataset. Therefore, there's no information on sample size for an algorithm test set, data provenance, or whether it was retrospective/prospective.
3. 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 / Not Provided. As there is no algorithm requiring a "ground truth" to be established for a test set, there is no mention of experts or their qualifications in this context. The "truth" for a mechanical implant typically comes from engineering standards and physical measurements.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
- Not Applicable / Not Provided. An adjudication method is used when multiple human readers disagree on ground truth. Since no human readers or ground truth establishment for a test set are mentioned, no adjudication method is applicable or described.
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
- No, not done. The document explicitly states: "No clinical testing was conducted to support this submission." Therefore, no MRMC study, AI assistance, or effect size is reported.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done
- No, not done. This device is a physical medical implant, not an algorithm. Standalone algorithm performance is not applicable.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- Not Applicable. For this physical device, "ground truth" would relate to its material properties and mechanical performance meeting engineering specifications and standards (e.g., ASTM F1717-04), rather than clinical outcomes or diagnostic accuracy. The document focuses on demonstrating "substantial equivalence" of the device's design, materials, and performance to predicate pedicle screw systems through non-clinical tests.
8. The sample size for the training set
- Not Applicable / Not Provided. There is no algorithm, and thus no training set or associated sample size for training data.
9. How the ground truth for the training set was established
- Not Applicable / Not Provided. No training set means no method for establishing its ground truth is described.
Summary of what the document does provide regarding device performance:
The document states that non-clinical tests, including those conducted in accordance with recognized standards like ASTM F1717-04, Standard Test Methods for Spinal Implant Constructs in a Vertebrectomy Model, "have demonstrated the substantial equivalence of the subject device to commercially-available predicate devices in terms of performance."
This implies a comparison of the mechanical and structural performance of the VertiFlex™ Spinal Screw System against the performance of predicate devices, adhering to industry-accepted testing standards. The "acceptance criteria" here are effectively met by demonstrating that the VertiFlex™ system performs comparably to the predicate devices under these standardized non-clinical tests. However, the exact numerical results or specific pass/fail thresholds from these tests are not detailed 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.