(67 days)
The Uni-Thread Spinal System is a pedicle screw system indicated for skeletally mature patients who:
- have severe spondylolisthesis (Grades 3 and 4) at the L5-S1 vertebra;
- receive fusions using autogenous bone graft only;
- have the device fixed or attached to the lumbar and sacral spine (L3 to sacrum); and
- have the device removed after the development of a solid fusion.
In addition, the Uni-Thread Spinal System is a pedicle screw system 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
- failed previous fusion (pseudoarthrosis)
The Uni-Threaad Spinal System instrumentation consists of screws, rods, and connectors that can be assembled in a variety of constructs. The instrumentation is combined and placed to treat a variety of spinal disorders, with the constructs varying according to the nature of the spinal pathology. The Uni-Thread System components are available in titanium alloy manufactured according to ASTM-F136.
The provided text describes a 510(k) premarket notification for the Uni-Thread™ Spinal System. This document focuses on establishing substantial equivalence to previously cleared devices rather than presenting data from a clinical study with specific acceptance criteria and performance metrics typically associated with AI/ML devices or novel diagnostic tools.
Therefore, the requested information regarding acceptance criteria, device performance, sample sizes for test and training sets, expert qualifications, adjudication methods, MRMC studies, or ground truth establishment is not available in the provided text. The submission relies on demonstrating similarity in design, material, and intended use to predicate devices, supported by a "beginning in" (likely meaning 'benchmark' or 'comparison') study to show equivalence of the construct design to currently marketed systems.
Here's a breakdown of why each requested point cannot be addressed from the given document:
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A table of acceptance criteria and the reported device performance: This document does not specify quantitative acceptance criteria for device performance or report specific performance metrics (e.g., sensitivity, specificity, accuracy) akin to what would be expected for an AI/ML or diagnostic device. The basis for clearance is "substantial equivalence" to predicate devices.
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Sample sized used for the test set and the data provenance: Not applicable. No "test set" in the context of AI/ML or diagnostic performance evaluation is mentioned. The "beginning in a was performed to demonstrate the equivalence of the construct design" likely refers to mechanical or engineering testing, but details are absent.
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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. There is no mention of human experts establishing ground truth for a test set.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set: Not applicable. No test set requiring expert adjudication is described.
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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 device is a spinal implant, not an AI-assisted diagnostic tool, so an MRMC study is irrelevant to its clearance.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: Not applicable. As a physical medical device (spinal system), the concept of "standalone algorithm performance" does not apply.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.): Not applicable in the context of diagnostic or AI performance. The "ground truth" for this device would be its mechanical and material properties meeting established standards, and its design being equivalent to predicate devices.
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The sample size for the training set: Not applicable. There is no mention of a training set as this is not an AI/ML device.
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How the ground truth for the training set was established: Not applicable. There is no mention of a training set.
In summary, the provided document relates to the clearance of a physical medical device (a spinal implant) based on its substantial equivalence to existing devices, not on the performance metrics of an AI/ML system.
§ 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.