(42 days)
The S4 Spinal System is intended for anterior/anterolateral and posterior, non-cervical pedicle and non-pedicle fixation. Fixation is limited to skeletally mature patients and is intended to be used as an adjunct to fusion using autograft or allograft. The device is indicated for treatment of the following acute and chronic instabilities or deformities:
1 ) degenerative disc disease (defined as discogenic back pain with degeneration of the disc confirmed by history and radiographic studies)
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spondylolisthesis,
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trauma (i.e., fracture or dislocation),
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spinal stenosis,
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deformities or curvatures (i.e., scoliosis, kyphosis, and/or lordosis),
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tumor,
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pseudoarthrosis, and
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failed previous fusion.
The S4 Spinal System consists of polyaxial screws and monoaxial screws of varying diameters and lengths, various hook styles, rods of varying lengths, fixed and adjustable cross-connectors, and various styles of 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.
The provided text describes a 510(k) premarket notification for the Aesculap® Implant Systems S4 Spinal System, specifically focusing on a line extension to include additional rod connectors. The evaluation largely relies on demonstrating substantial equivalence to predicate devices through non-clinical performance testing.
Here's an analysis of the acceptance criteria and study described, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Mechanical Performance (Non-Clinical): | |
| Static Axial Compression Bending (ASTM F1717-11a) | Results showed that the subject Aesculap S4 Rod Connectors meet or exceed the performance of the predicate devices. |
| Dynamic Axial Compression Bending (ASTM F1717-11a) | Results showed that the subject Aesculap S4 Rod Connectors meet or exceed the performance of the predicate devices. |
| Static Torsion (ASTM F1717-11a) | Results showed that the subject Aesculap S4 Rod Connectors meet or exceed the performance of the predicate devices. |
| Material Equivalence: | Manufactured from Titanium and Titanium Alloy, which is the same material as the predicate devices. |
| Dimensional & Design Equivalence: | Components are offered in similar shapes and sizes as the predicate devices. |
| Indications for Use Equivalence: | Intended for the same indications for use as the predicate devices (anterior/anterolateral and posterior, non-cervical pedicle and non-pedicle fixation, for skeletally mature patients as an adjunct to fusion for various spinal instabilities/deformities). |
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size: The document does not specify a "sample size" in the context of clinical test subjects or datasets as would be common for AI/diagnostic device studies. Instead, it refers to non-clinical testing of the physical device components. The sample size for these non-clinical tests (e.g., number of rod connectors tested) is not provided.
- Data Provenance: Not applicable in the context of clinical data provenance. The "data" here comes from laboratory mechanical testing of physical devices.
3. Number of Experts Used to Establish Ground Truth and Qualifications:
- Not applicable. This submission is for a physical spinal implant system, not a diagnostic or AI-driven device requiring expert consensus for ground truth establishment. The "truth" in this context is determined by adherence to ASTM standards and mechanical performance metrics compared to predicate devices.
4. Adjudication Method for the Test Set:
- Not applicable. There is no "test set" in the sense of clinical cases requiring expert adjudication. The performance is assessed through standardized mechanical testing methods per ASTM F1717-11a.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- Not applicable. This is a spinal implant, not a diagnostic imaging or AI-assisted interpretation device that would involve human readers.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study:
- Not applicable. This submission describes a physical medical device, not an algorithm or software.
7. Type of Ground Truth Used:
- For the performance studies, the "ground truth" implicitly refers to the specified performance criteria set by ASTM standards (F1717-11a) for static axial compression bending, dynamic axial compression bending, and static torsion, as well as the performance profiles of legally marketed predicate devices. The device's performance is compared against these benchmarks rather than a clinical ground truth like pathology or outcome data.
8. Sample Size for the Training Set:
- Not applicable. This device is not an AI/machine learning model, so there is no training set in the conventional sense.
9. How the Ground Truth for the Training Set Was Established:
- Not applicable. As there is no training set, this question is not relevant.
In summary: The provided document describes the regulatory pathway for a spinal implant system, which primarily involves demonstrating mechanical equivalence to predicate devices through standardized non-clinical testing. It does not involve AI, diagnostic algorithms, or human-in-the-loop performance studies.
§ 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.