(441 days)
The TRANSITION™ Stabilization System is intended to provide immobilization and stabilization of spinal segments as an adjunct to fusion in the treatment of the following acute and chronic instabilities or deformities of the thoracic, lumbar and sacral spine in skeletally mature patients: degenerative spondylolisthesis with objective evidence of neurologic impairment, kyphosis, and failed previous fusion (pseudoarthrosis).
In addition, the TRANSITION™ Stabilization System is indicated for use in patients: who are receiving fusions with autogenous graft only; who are having the device fixed or attached to the lumbar or sacral spine; and who are having the device removed after the development of a solid fusion mass.
TRANSITION™ is only indicated for use when fusion with autogenous bone graft is being performed at all instrumented levels.
The TRANSITION™ Stabilization System implants include pedicle screws and implant assemblies which are provided pre-assembled or can be assembled intraoperatively.
TRANSITION™ pedicle screws are coated with hydroxyapatite (HA). Either TRANSITION™ HA coated pedicle screws or specified REVERE® pedicle screws may be used in conjunction with the implant assemblies. Specifically, REVERE® polyaxial (solid, cannulated and dual outer diameter) screws and monoaxial screws 6.5mm diameter and larger, and 35mm length and larger, may be used with the TRANSITION™ implant assemblies.
Implant assemblies consist of a polyethylene terepthalate (PET) cord, polycarbonate urethane (PCU) spacers and bumpers, and titanium alloy spools, end spools and set screw ends. The cord passes through the entire implant such that the spools are positioned to sit within the screw heads and the spacer sits between the spools. The end spool includes one end of the secured cord. The bumper followed by a set screw end is positioned at the other end of the cord.
Implant assemblies are available in single or multi-level configurations. REVERE® locking caps with inner set screws are used to rigidly connect the pedicle screws to the implant assemblies.
TRANSITION™ implants are available in a variety of sizes to accommodate varied patient anatomy.
TRANSITION™ implants are manufactured from titanium alloy Ti6AI4V (ASTM F136) or Ti6Al7Nb (ASTM F1295), polyethylene terepthalate (PET), and/or polycarbonate urethane (PCU). Titanium alloy TRANSITION™ screws are hydroxyapatite (HA) coated (ASTM F1185).
The provided text is a 510(k) summary for the TRANSITION™ Stabilization System, which is a medical device. This type of document is a regulatory submission to the FDA (Food and Drug Administration) to demonstrate that a medical device is substantially equivalent to a legally marketed predicate device.
The context of this document is therefore not a study proving device performance against acceptance criteria in the way a research paper or clinical trial might. Instead, the "acceptance criteria" here refer to regulatory requirements for substantial equivalence, and the "study" is the information provided by the manufacturer to demonstrate that equivalence.
Consequently, many of the requested categories (like sample size for test/training sets, data provenance, number/qualification of experts, adjudication methods, MRMC studies, standalone performance, type of ground truth) are not applicable or not present in a 510(k) summary as it is primarily focused on demonstrating equivalence to an already approved device through comparisons of indications, design, materials, and potentially some mechanical testing data (though not detailed here).
Here's an analysis based on the provided text:
Acceptance Criteria and Device Performance
1. Table of Acceptance Criteria and Reported Device Performance
Acceptance Criteria for Substantial Equivalence (as understood in a 510(k) submission):
The primary "acceptance criteria" for a 510(k) submission like this are that the device is substantially equivalent to a legally marketed predicate device in terms of:
- Intended Use/Indications for Use: The new device has the same intended use as the predicate.
- Design and Function: The device has similar technological characteristics (e.g., materials, principle of operation, mechanical properties).
- Safety and Effectiveness: Differences in technological characteristics do not raise new questions of safety and effectiveness.
Reported Device Performance (as summarized in the document):
| Criteria Category | Predicate Device(s) | TRANSITION™ Stabilization System Performance/Characteristics | Equivalence Claim |
|---|---|---|---|
| Intended Use/Indications for Use | REVERE (K061202), Dynesys (K031511) | Intended to provide immobilization and stabilization of spinal segments as an adjunct to fusion in the treatment of acute and chronic instabilities or deformities of the thoracic, lumbar and sacral spine in skeletally mature patients (degenerative spondylolisthesis, kyphosis, failed previous fusion). Indicated for use with autogenous graft only, fixation to lumbar or sacral spine, and removal after solid fusion mass. Specific limitation added by FDA: Not established for spinal stabilization without fusion; only for use when fusion with autogenous bone graft is being performed at all instrumented levels. | The TRANSITION™ Stabilization System has been found to be substantially equivalent to the previously cleared predicate devices in terms of indications for use. |
| Device Description/Function | REVERE (K061202), Dynesys (K031511) | Includes pedicle screws (HA coated or specified REVERE® screws) and implant assemblies. Implant assemblies consist of: PET cord, PCU spacers/bumpers, titanium alloy spools/end spools/set screw ends. Cord passes through components, securing spools and spacers. Uses REVERE® locking caps. Available in single or multi-level configurations and various sizes. | The TRANSITION™ Stabilization System has been found to be substantially equivalent to the previously cleared predicate devices in terms of design and function. |
| Materials | REVERE (K061202), Dynesys (K031511) | Manufactured from titanium alloy Ti6AI4V (ASTM F136) or Ti6Al7Nb (ASTM F1295), polyethylene terepthalate (PET), and/or polycarbonate urethane (PCU). Titanium alloy TRANSITION™ screws are hydroxyapatite (HA) coated (ASTM F1185). | The TRANSITION™ Stabilization System has been found to be substantially equivalent to the previously cleared predicate devices in terms of materials. |
| Overall Equivalence | REVERE (K061202), Dynesys (K031511) | No direct performance metrics (e.g., tensile strength, fatigue life numbers) are explicitly stated in this summary, but would have been part of the full 510(k) submission showing similarity to predicates. | "The TRANSITION™ Stabilization System has been found to be substantially equivalent to the previously cleared predicate devices in terms of indications for use, design, function, and materials." |
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 in this 510(k) summary. This document does not detail specific clinical or analytical studies with test sets in the typical research sense. The "study" here is the comparison to predicate devices, usually supported by design specifications, material testing, and potentially bench testing data, none of which are detailed here with sample sizes or data provenance.
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. Ground truth determination by experts is typically for diagnostic/AI devices, not for spinal implant systems demonstrating substantial equivalence to predicates.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not applicable/Not provided. This is not relevant for a 510(k) submission for a spinal implant device.
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/Not provided. MRMC studies are for diagnostic imaging devices, not spinal implants.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable/Not provided. This device is a physical spinal implant, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- Not applicable/Not provided in this summary. For a 510(k) of this nature, the "ground truth" for showing safety and effectiveness is largely based on the established safety and effectiveness of the predicate devices, combined with engineering analysis and bench testing to demonstrate similar performance characteristics.
8. The sample size for the training set
- Not applicable/Not provided. There is no "training set" in the context of an AI/machine learning model for this physical medical device.
9. How the ground truth for the training set was established
- Not applicable/Not provided. As there is no training set, this question is not relevant.
§ 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.