(57 days)
The S-LOK™ PSS 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 thoracic, lumbar, and sacral spine: degenerative spondylolisthesis with objective evidence of neurological impairment, fracture, dislocation, scoliosis, spinal tumor, and failed previous fusion (pseudoarthrosis).
The S-LOK™ PSS System is also intended for non-cervical pedicle screw fixation for the following indications: severe spondylolisthesis (grades 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 (L3 to sacrum) with removal of the implants after the attainment of a solid fusion. It is also intended for the following indications: trauma (i.e. fracture or dislocation); spinal stenosis; curvatures (i.e. scoliosis, kyphosis, and/or lordosis); spinal tumor; pseudoarthrosis; and failed previous fusion.
The S-LOK™ PSS System is a top-loading, multiple component, posterior spinal fixation system which consists of pedicle screws, rods, cross links, locking cap screws and hooks. All of the components are available in a variety of sizes to match more closely the patient's anatomy.
Here's an analysis of the provided text regarding the S-LOK™ PSS Pedicle Screw System's acceptance criteria and studies:
Acceptance Criteria and Device Performance
| Acceptance Criteria Type | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Mechanical Testing | Static axial gripping (per ASTM F1798) | Equivalent to predicate device(s) |
| Static flexion/extension moment (per ASTM F1798) | Equivalent to predicate device(s) | |
| Biomechanical Testing | Cadaver study | Equivalent to predicate device(s) |
Study Details
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Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective):
- The document mentions a "cadaver study" but does not specify the sample size (number of cadavers or specific test subjects).
- The provenance of the data (country of origin, retrospective/prospective) is not specified.
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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):
- This information is not provided in the document. The studies conducted are mechanical and biomechanical, not clinical studies involving expert interpretation for ground truth.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable. The studies are mechanical/biomechanical, not involving human adjudication of results.
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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:
- No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. The device is a pedicle screw system, not an AI diagnostic tool.
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If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- No, a standalone (algorithm-only) performance study was not done. The device is a physical medical implant, not an algorithm.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- For the mechanical tests (Static axial gripping, Static flexion/extension moment), the ground truth is derived from the established ASTM F1798 standard and comparison to the predicate device's performance under similar testing conditions.
- For the cadaver study, the ground truth would be based on biomechanical measurements and observations of the system's performance within the cadaveric spine, again likely in comparison to the predicate device.
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The sample size for the training set:
- Not applicable. This is a physical medical device, not an AI/machine learning model that requires a training set.
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How the ground truth for the training set was established:
- Not applicable, as there is no training set for this type of device.
§ 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.