(69 days)
The S4 Spinal System, when used as a pedicle screw fixation system, is indicated for use in patients: a) having severe spondylolisthesis (Grade 3 and 4) at the L5-S1 ioin: b) who are receiving fusion using autogenous graft only; c) who are having the device fixed or attached to the lumbar or sacral spine; and d) who are having the device removed after the development of a solid fusion mass may not go above the L5-S1 joint, the levels of pedicle screw fixation may span from L3 to the sacrum.
The S4 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 spin: degenerative spondyloisthesis with objective evidence of neurological impairment, fracture, dislocation, scoliosis, spinal tumor, and failed previous fusion (pseudarthrosis).
When used as a hook and sacral screw system (other than pedicle screw fixation system for high grade spondylolisthesis), the S4 Spinal System is intended for use in the treatment of degenerative disc disease (as defined by chronic back pain of discogenic origin with the degeneration of the disc confirmed by a history and radiographic studies), idiopathic scoliosis, spondylolisthesis, kyphotic or lordotic deformity of the spine, loss of stability due to tumors, spinal stenosis, vertebral fracture of dislocation, pseudoarthrosis, and previous failed spinal surgery/fusion. When used for this indication, screws of the S4 Spinal System are intended for sacral/iliac attachment only. Hooks and transverse connectors of the system are intended for posterior throracic and/or lumbar use only. The levels of use for hook and sacral screw fixation of this system are T1 to the sacrum.
The S4 Spinal System consists of polyaxial screws and monoaxial screws of varying diameters and lengths, various hook styles, rods of varying lengths, and fixed and adjustable rod to rod connectors. All implant components are top loading and top tightening. The S4 Spinal System is manufactured from Titanium and Titanium alloy in accordance with ISO 5832/3 and ISO 5832/2.
Here's an analysis of the provided text regarding the S4 Spinal System, focusing on information typically found in acceptance criteria and study designs for medical devices.
Important Note: The provided document is a 510(k) summary and an FDA clearance letter for a line extension of an existing spinal system. It primarily focuses on demonstrating substantial equivalence to predicate devices based on technological characteristics and mechanical testing. It does not describe a study involving human or animal subjects to assess clinical performance or comparative effectiveness with human readers using AI. Therefore, many of the requested fields related to clinical studies, human readers, and ground truth establishment will be marked as "Not Applicable" or "Not Provided" based on the content.
Acceptance Criteria and Device Performance
The document does not explicitly state quantitative "acceptance criteria" in the format of specific performance metrics that the device had to achieve for clinical efficacy (e.g., success rates, complication rates). Instead, the acceptance is based on demonstrating substantial equivalence to existing, legally marketed predicate devices through technological similarities and mechanical performance testing.
Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria (Implicit from Submission) | Reported Device Performance (Summary from Submission) |
|---|---|---|
| Material Equivalence | Material composition must be same as predicate or an accepted biocompatible material. | Manufactured from Titanium and Titanium alloy in accordance with ISO 5832/3 and ISO 5832/2, same as predicate devices. |
| Design/Dimensional Equivalence | Similar shapes and sizes to predicate devices. | New components are offered in similar shapes and sizes as the predicate devices. All implant components are top loading and top tightening. |
| Mechanical Performance | Must meet relevant standards for spinal implants (fatigue, static strength, etc.). | "All required testing per 'Draft Guidance for the Preparation of Premarket Notifications (510(k)s) Applications for Orthopedic Devices-The Basic Elements' were done where applicable. In addition, testing per the 'Spinal System 510(k)s' was completed where applicable." |
| Intended Use Equivalence | Indications for use must be same or a subset of predicate device indications. | Indications for use are consistent with the predicate devices, covering various spinal conditions requiring fusion and stabilization. |
Study Details (Based on Provided Text)
Given the nature of a 510(k) submission for a line extension of an orthopedic implant, the "study" referred to is almost entirely mechanical and material testing, not a clinical study involving human patients or AI algorithms.
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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):
- Sample Size: Not specified for individual tests. The "test set" refers to the physical device components subjected to mechanical tests. The number of components tested for each specific mechanical evaluation (e.g., fatigue, static bending) is not provided in this summary.
- Data Provenance: Not applicable in the context of geographical origin for mechanical testing. The testing was conducted internally or by accredited labs as part of the manufacturer's due diligence for regulatory submission. It is inherently prospective in the sense that the new components were manufactured and then tested to demonstrate performance.
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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. The "ground truth" for mechanical testing is established by engineering standards and specifications (e.g., ISO standards, FDA guidance documents for spinal systems), not by human expert consensus or clinical interpretation.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- None. Adjudication methods like 2+1 or 3+1 refer to resolving discrepancies among human expert reviewers in clinical studies. This is not relevant for mechanical testing. Mechanical test results are objective measurements against defined pass/fail criteria.
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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, an MRMC comparative effectiveness study was not done. This is a mechanical device, not an AI-assisted 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 performance study was not done. This device does not involve any AI algorithms.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- Engineering Standards and Specifications. The "ground truth" for the performance of this device in a 510(k) context consists of meeting predefined mechanical performance limits and material specifications outlined in national and international standards (e.g., ISO 5832 series for materials, and relevant FDA guidance documents for spinal implants concerning fatigue, static strength, and construct integrity).
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The sample size for the training set:
- Not Applicable. There is no "training set" in the context of a mechanical device.
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How the ground truth for the training set was established:
- Not Applicable. 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.