(77 days)
The Spineology Threshold™ V2 Pedicular Fixation System is intended for posterior, non-cervical fixation as an adjunct to fusion in skeletally mature patients for the following indications: degenerative disc disease (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies) spondylolisthesis; trauma (i.e., fracture or dislocation); spinal stenosis; curvatures (i.e., scoliosis, kyphosis and/or lordosis); tumor; pseudoarthrosis; and/or failed previous fusion.
The Spineology Threshold Pedicular Fixation System consists of solid standard and reduction screws (titanium alloy), curved and straight rods (titanium alloy), and adjustable ConneX Cross Connector and fixed Connex Rod Connector (titanium alloy) devices to allow the surgeon to build an implant system to fit the patient's anatomical and physiological requirements. Threshold solid standard and reductions screws are available with or without a hydroxyapatite coating. The system is intended to provide immobilization and stabilization of spinal segments in skeletally mature patients as an adjunct to fusion in the treatment of acute and chronic instabilities or deformities of the thoracic, lumbar, and sacral spine. The solid standard and reduction screws can be placed in the pedicles in a variety of trajectories ranging from the standard anatomic transpedicular path projected medially toward the ventral vertebral body, to a caudocephalad path sagittally and a laterally directed path in the transverse plane.
This document describes the Spineology Threshold™ V2 Pedicular Fixation System, a medical device, and its clearance through a 510(k) premarket notification. The information provided is primarily focused on demonstrating substantial equivalence to previously marketed predicate devices, rather than a standalone clinical study with detailed acceptance criteria and performance metrics for a diagnostic or AI-driven device.
Therefore, many of the requested categories (e.g., sample size for test set, number of experts, MRMC study, ground truth for training set) are not applicable to this type of regulatory submission and device. This is a spinal fixation system, not a device that relies on interpretation, diagnostic accuracy, or AI.
However, I can extract the relevant information regarding acceptance criteria derived from non-clinical testing and the studies that demonstrate compliance.
1. A table of acceptance criteria and the reported device performance
For a spinal fixation system, "acceptance criteria" and "reported device performance" are typically defined by compliance with established mechanical testing standards and comparison to predicate device performance. The document explicitly states:
- "New mechanical testing was not required to establish the performance of Threshold V2 pedicle screws, pre-bent rods, and set screws. These devices were previously cleared under a separate 510(k) and have not been modified since their initial clearance." This implies that their previous performance met the relevant standards.
- "New mechanical testing was not required to support the performance of Threshold V2 reduction screws. These screws are identical to previously cleared Threshold V2 pedicle screws with the exception of the integrated removable (non-implanted) extension towers on the tulip of the device." Again, reliance on previous clearance and identical mechanical properties.
- For Straight Rods and ConneX™ Cross Connectors and ConneX™ Rod Connectors, specific ASTM tests were conducted. The "acceptance criteria" for these would be to meet or exceed the performance of the predicate devices and the requirements outlined in the referenced ASTM standards and FDA Guidance. While specific numerical performance values are not provided in this summary, the conclusion of the submission is that the device "has been shown to be substantially equivalent to the legally marketed predicate devices," implying successful performance in these tests.
Therefore, the table would look like this, with the understanding that "reported performance" is demonstrated by substantial equivalence and meeting standard requirements rather than specific numerical data points explicitly stated here:
| Acceptance Criteria (Implied) | Reported Device Performance (Demonstrated by) |
|---|---|
| Maintain performance of previously cleared pedicle screws, pre-bent rods, and set screws. | No new mechanical testing required, as these components were previously cleared and unmodified. Their performance is considered equivalent to the predicate devices and compliant with applicable standards from their original clearance. |
| Maintain performance of previously cleared pedicle screws for reduction screws. | No new mechanical testing required, as reduction screws are identical to previously cleared V2 pedicle screws (excluding non-implanted extension towers). Performance is considered equivalent. |
| Meet mechanical requirements for Straight Rods as per FDA Guidance: Spinal System 510(k)s (2004) and ASTM F1717-15. | Static Compression Bending testing was conducted on representative Straight Rod devices in accordance with ASTM F1717-15 and FDA Guidance. The conclusion of the submission states substantial equivalence, indicating successful performance in these tests. |
| Meet mechanical requirements for ConneX™ Cross Connectors and ConneX™ Rod Connectors as per FDA Guidance: Spinal System 510(k)s (2004), ASTM F1717, ASTM F1798, and ASTM F2193. | Flexural Grip (ASTM F1798), Static Cantilever Bending (ASTM F2193), Static Compression Bending (ASTM F1717), and Dynamic Compression Bending (ASTM F1717) testing was conducted on representative worst-case devices in accordance with the specified standards and FDA Guidance. The conclusion of the submission states substantial equivalence, indicating successful performance in these tests. |
| Compliance with bacterial endotoxin limits. | Bacterial endotoxin testing (BET) was conducted for all Threshold V2 devices in accordance with ANSI/AAMI ST-72:2011. The successful conclusion of the submission implies compliance. |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size for Test Set: Not applicable in the context of clinical studies for diagnostic accuracy. For mechanical testing, representative "worst-case" devices were tested, a standard practice for non-clinical verification. Specific numerical sample sizes for each test are not provided in this summary but would be detailed in the full test reports.
- Data Provenance: Not applicable for a clinical study. The mechanical testing data would originate from the manufacturer's testing facilities or a certified lab. The document does not specify the country of origin for the testing itself, but Spineology Inc. is located in Saint Paul, MN, USA.
- Retrospective or Prospective: Not applicable, as this is non-clinical mechanical testing, not a clinical study.
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. This device is a pedicular fixation system (an implant for spine surgery), not a diagnostic device requiring expert interpretation or ground truth establishment for a test set.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not applicable.
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 not an AI-assisted diagnostic or interpretation device.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- Not applicable for clinical ground truth. For mechanical testing, the "ground truth" is compliance with established engineering standards (ASTM and FDA Guidance) and performance comparable to predicate devices.
8. The sample size for the training set
- Not applicable. This device does not have a "training set" in the context of machine learning or AI.
9. How the ground truth for the training set was established
- Not applicable.
§ 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.