(86 days)
When used as a pedicle screw fixation system, the NuVasive MAS PLIF Fixation 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 or deformities of the posterior thoracic, lumbar, and sacral spine: (1) degenerative disc disease (as defined by back pain of discogenic origin with degeneration of the disc confirmed by patient history and radiographic studies), (2) degenerative spondylolisthesis with objective evidence of neurologic impairment, (3) fracture, (4) dislocation, (5) scoliosis, (6) kyphosis, (7) spinal tumor, and/or (8) failed previous fusion (pseudoarthrosis).
When used for posterior non-cervical screw fixation in pediatric patients, the NuVasive MAS PLIF Fixation System implants are indicated as an adjunct to treat adolescent idiopathic scoliosis. Additionally the NuVasive MAS PLIF Fixation System is intended to treat pediatic patients diagnosed with the following conditions: spondylolisthesis / spondylolysis, and fracture caused by tumor and/or trauma. Pediatic pedicle screw fixation is limited to a posterior approach and is intended to be used with autograft and/or allograft.
The Nu Vasive MAS PLIF Fixation System is also indicated for the treatment of severe spondylolisthesis (Grades 3 and 4) of the L5-S1 vertebral joint in skeletally mature patients receiving fusion by autogenous bone graft, having the device fixed or attached to the lumbar and sacral spine (L3 to sacrum), with removal of the implants after attainment of a solid fusion.
When used as an anterolateral non-pedicle screw system in the thoracic and lumbar spine, the NuVasive MAS PLF Fixation System is also intended for the following indications: (1) degenerative disc disease (as defined by back pain of discogenic origin with degeneration of the disc confirmed by patient history and radiographic studies), (2) spinal stenosis, (3) spondylolisthesis, (4) spinal deformities, (5) fracture, (6) pseudoarthosis, (7) tumor resection, and/or (8) failed previous fusion.
The NuVasive MAS PLIF Fixation System is a pedicle screw system that consists of a variety screws, lock screws, rods and associated general instruments. Implant components are available in a variety sizes and can be rigidly locked into a variety of different configurations to suit the individual pathology and anatomical conditions of the patient.
The provided document is a 510(k) summary for the NuVasive® MAS® PLIF Fixation System, a medical device for spinal fusion. This type of submission focuses on demonstrating substantial equivalence to a predicate device, rather than proving efficacy through clinical outcome studies with acceptance criteria for device performance in terms of diagnostic metrics. Therefore, the document does not contain the detailed information necessary to fully answer your request regarding acceptance criteria, study design for device performance, ground truth, or MRMC studies for AI devices.
However, I can extract information related to the non-clinical testing performed to demonstrate substantial equivalence, which serves a similar purpose in the context of this device's regulatory pathway.
Here's a summary of the information that can be extracted, and where the requested details are not applicable or not provided:
1. Table of Acceptance Criteria and Reported Device Performance
For the specific type of device (spinal fixation system) and regulatory submission (510(k)), the "acceptance criteria" and "reported device performance" are based on mechanical testing standards rather than diagnostic metrics like sensitivity or specificity.
| Acceptance Criteria (Standard Compliance) | Reported Device Performance |
|---|---|
| Static Compression Bending per ASTM F1717 | Compliant / Substantially Equivalent to Predicate |
| Dynamic Compression Bending per ASTM F1717 | Compliant / Substantially Equivalent to Predicate |
| Static Torsion per ASTM F1717 | Compliant / Substantially Equivalent to Predicate |
| Tulip pull-off | Compliant / Substantially Equivalent to Predicate |
Note: The document states, "The results demonstrate that the subject NuVasive MAS PLIF Fixation System is substantially equivalent to the predicate." This is the reported device performance in the context of a 510(k) submission for mechanical medical devices. Specific numerical values or thresholds for "acceptance" are not detailed but are implied by adherence to the named ASTM standards and comparison to the predicate device.
2. Sample size used for the test set and the data provenance
- Sample size for test set: Not specified in the provided document. For mechanical testing of this nature, "samples" typically refer to the number of device components tested according to the ASTM standards.
- Data provenance: Not applicable in the context of mechanical testing. This device is not an AI or diagnostic device that uses patient data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not applicable. As this is a mechanical device, ground truth is established by standardized mechanical testing protocols (ASTM standards) and engineering principles, not expert human interpretation.
4. Adjudication method for the test set
- Not applicable. Mechanical tests have objective results (e.g., force, displacement), not subjective interpretations requiring adjudication.
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 spinal fixation system, not an AI or diagnostic device, so MRMC studies are irrelevant.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable. This is a physical medical device, not an algorithm.
7. The type of ground truth used
- For mechanical performance: adherence to ASTM F1717 standards for Static Compression Bending, Dynamic Compression Bending, and Static Torsion, and an unspecified "Tulip pull-off" test. The "ground truth" is defined by the technical specifications and performance characteristics of the predicate device and the requirements of the standards.
8. The sample size for the training set
- Not applicable. This device does not involve a "training set" in the machine learning sense.
9. How the ground truth for the training set was established
- Not applicable.
In summary:
The provided document describes a mechanical medical device (spinal fixation system) and its 510(k) submission, which focuses on demonstrating substantial equivalence to existing predicate devices through non-clinical (mechanical) testing. The questions posed are primarily relevant to AI/diagnostic devices and clinical performance studies, which are not detailed or applicable in this document. The "acceptance criteria" here are compliance with specified ASTM international standards for mechanical performance, and "device performance" is established by showing equivalency to the predicate device under these tests.
§ 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.