(56 days)
When used as a posterior pedicle screw fixation system, the Synthes Posterior Universal Spinal System devices are 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: degenerative spondylolisthesis with objective evidence of neurologic impairment, fracture, dislocation, scoliosis, kyphosis, spinal tumor, and failed previous fusion (pseudarthrosis).
In addition, the Synthes Posterior Universal Spinal System is intended for treatment of severe spondylolisthesis (Grade 3 and 4) of the L5 - S1 vertebra in skeletally mature patients receiving fusion by autogenous bone graft having implants attached to the lumbar and sacral spine with removal of the implants after the attainment of a solid fusion. The levels of pedicle screw fixation for these patients are L3-S2.
When used as a posterior non-pedicle screw fixation system, Synthes Posterior Universal Spinal System devices are intended for scoliotic, lordotic, or kyphotic deformities (such as scoliosis, Schuermann's disease), degenerative disease (back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies), and fractures of the posterior thoracolumbar spine. In addition, when used with the 3.5mm / 6.0mm parallel connector, the Synthes Posterior Universal Spinal System can be linked to the Posterior Cervical/Thoracic Hook/Rod System.
Synthes Posterior Universal Spinal System. This system consists of stainless steel or titanium components and associated manual surgical instruments. The components include rods, hooks, side-opening screws with collar and nut, variable axis screws with connector, collar, locking ring and nut, trans-connector system, open and closed transverse bars, parallel connectors, Schanz screws, and clamp with posterior nut.
This document describes the Synthes Posterior Universal Spinal System, a medical device. The information provided is a Premarket Notification (510(k)) Summary to the FDA, which focuses on demonstrating substantial equivalence to previously cleared devices rather than extensive clinical studies for novel technologies.
Therefore, many of the requested elements for a study proving acceptance criteria (like sample sizes for test/training sets, ground truth establishment details, expert qualifications, adjudication methods, or MRMC studies) are not typically included or required in a 510(k) submission for this type of device.
The "acceptance criteria" here refer to the safety and effectiveness requirements for spinal fixation systems, which are satisfied through a combination of design, material testing, and a comparison to predicate devices that have already met these criteria.
Here's an attempt to address your request based on the provided text, recognizing the limitations of a 510(k) summary for a mechanical device:
Acceptance Criteria and Device Performance for the Synthes Posterior Universal Spinal System (K982987)
1. Table of Acceptance Criteria and Reported Device Performance
For medical devices like the Synthes Posterior Universal Spinal System, the "acceptance criteria" are generally established through
- Regulatory Standards: Adherence to established FDA regulations and guidance for spinal fixation systems.
- Performance Benchmarks: Demonstrated equivalence in mechanical and material properties to legally marketed predicate devices.
- Intended Use Compatibility: The device must perform its intended function (immobilization and stabilization of spinal segments, acting as an adjunct to fusion) safely and effectively within the specified indications.
The provided 510(k) summary indicates that the device meets these criteria through a claim of "substantial equivalence" to previously cleared Synthes spinal systems.
| Acceptance Criteria Category (Implied) | Specific Criterion (Implied/Stated) | Reported Device Performance | Source/Evidence (Implied) |
|---|---|---|---|
| Safety and Effectiveness | Substantial equivalence to legally marketed predicate devices. | "Device is substantially equivalent... to devices marketed in interstate commerce prior to May 28, 1976..." | FDA 510(k) Clearance Letter |
| Mechanical Strength/Integrity | Satisfying requirements for posterior thoracolumbar and sacral fixation. | "...supported by testing which satisfies the requirements of posterior thoracolumbar and sacral fixation." | Testing (details not provided in summary) |
| Biocompatibility | Materials (stainless steel or titanium) are suitable for implantation. | Device components are made of "stainless steel or titanium." | Material specification (implicit) |
| Indications for Use | Meets the specified clinical conditions for which the device is intended. | Detailed list of indications provided (e.g., degenerative spondylolisthesis, fracture, scoliosis, kyphosis, spinal tumor, failed fusions, severe spondylolisthesis grades 3 & 4). | 510(k) Summary, Indications for Use Statement |
| Design and Features | Components are consistent with established spinal systems and allow for intended surgical approaches. | "This system consists of stainless steel or titanium ... rods, hooks, side-opening screws... etc." "This system is identical to previously cleared Synthes spinal systems..." | 510(k) Summary Device Description |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not applicable in the context of a 510(k) for a mechanical spinal system. This submission relies on in vitro mechanical testing and comparison to predicate devices, not patient-specific test sets or clinical trial data in the way an AI diagnostic device would. There is no mention of a "test set" in the context of patient data.
- Data Provenance: Not applicable. The "data" here refers to the design specifications, material properties, and mechanical test results of the device and its predicate, rather than retrospective or prospective clinical data from human subjects.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications
- Not applicable. The "ground truth" for a mechanical spinal implant demonstrating substantial equivalence is based on engineering principles, material science, and the functional success of predicate devices. Clinical "ground truth" (e.g., pathology, imaging expert consensus) as you might find for an AI diagnostic device is not the basis of this 510(k) submission.
4. Adjudication Method for the Test Set
- Not applicable. There is no "test set" requiring adjudication by clinical experts in this 510(k) submission.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No, not done. This is a mechanical device, not an AI-assisted diagnostic or treatment planning system. MRMC studies are designed to assess the performance of diagnostic tools (often AI) in a clinical setting compared to human readers.
6. Standalone Performance Study (Algorithm Only Without Human-in-the-Loop Performance)
- Not applicable. This device is a mechanical implant, designed to be implanted by a human surgeon. It does not operate as a standalone algorithm.
7. Type of Ground Truth Used
- For regulatory purposes in this 510(k), the "ground truth" for claiming substantial equivalence is based on:
- Engineering principles and biomechanical testing: The device's ability to withstand anticipated physiological loads and perform its mechanical function.
- Performance of predicate devices: The established safety and effectiveness of similar, legally marketed spinal systems.
- Material specifications: The known properties and biocompatibility of stainless steel and titanium.
8. Sample Size for the Training Set
- Not applicable. There is no "training set" for an AI algorithm associated with this mechanical device.
9. How the Ground Truth for the Training Set Was Established
- Not applicable. As there is no training set, there is no ground truth for it to be established.
Summary of the 510(k) Assessment Approach:
The FDA's review for this device (K982987) focused on substantial equivalence. This means the manufacturer (Synthes) demonstrated that their new "Posterior Universal Spinal System" is as safe and effective as a legally marketed predicate device(s) that already had FDA clearance. The key elements for this determination mentioned in the summary are:
- Identification of Predicate Device(s): The submission states, "This system is identical to previously cleared Synthes spinal systems."
- Performance Testing: "supported by testing which satisfies the requirements of posterior thoracolumbar and sacral fixation." While specific details of this testing (e.g., fatigue, static strength) are not in the public summary, such tests would have been performed and submitted to the FDA to demonstrate equivalence in mechanical performance.
- Material Equivalence: The use of "stainless steel or titanium" which are well-established materials for spinal implants.
- Indications for Use Equivalence: The stated indications for use are carefully compared to those of the predicate device(s) to ensure they fall within acceptable parameters for substantial equivalence.
In essence, for this type of device, the "study" proving acceptance criteria typically involves benchtop mechanical testing, material characterization, and a detailed comparison of design and indications for use against predicate devices, rather than clinical trials with patient populations or complex AI performance metrics.
§ 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.