(84 days)
The Zodiac® Polyaxial Spinal Fixation System is intended for use as a posterior spinal fixation device to aid in the surgical correction of various spinal deformities and pathologies of the spine. It is intended to provide stabilization during the development of fusion utilizing a bone graft. Specific indications for the Zodiac® Polyaxial Spinal Fixation System are dependent in part on the configuration of the assembled device and the method of attachment to the spine.
It is intended that this device, in any system configuration, be removed after development of solid fusion mass. Hook component indications are limited to T7-L5. Sacral-iliac screw indications are limited to the sacrum-iliac crest only.
- The Zodiac® Polyaxial Spinal Fixation System when used as a hook and sacral iliac screw fixation system (nonpedicle screw) is intended for:
a. Patients having fractures of the thoracic and lumbar spine.
b. Patients having deformity (i.e. idioscoliosis, neuromuscular scoliosis or kyphoscoliosis with associated paralysis or spasticity).
c. Patients having spondylolisthesis (i.e. isthmic spondylolisthesis, degenerative spondylolisthesis, and acute pars fracture allowing spondylolisthesis).
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The Zodiac® Polyaxial Spinal Fixation System, when used as a pedicle screw system in the thoraco-lumbo-sacral iliac region of the spine is intended for degenerative spondylolisthesis with objective evidence of neurologic impairment, fracture, dislocation, scoliosis, kyphosis, spinal tumor and failed previous fusion (pseudoarthrosis).
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In addition, the Zodiac® Polyaxial Spinal Fixation System, when used as a pedicle screw system is intended for:
a. Patients receiving autograft or allograft bone.
b. Patient having the device fixed or attached to the lumbar and sacral iliac spine and having severe spondylolisthesis grade 3 or 4 at the fifth lumbar-first sacral (L5-S1) vertebral joint.
- The Zodiac® Polyaxial Spinal Fixation System, when used as a laminar hook and bone screw system is intended for:
a. Patients having fractures of thoracic and lumbar spine.
b. Patients having thoracolumbar deformity (i.e. idioscoliosis, neuromuscular scoliosis, kyphoscoliosis or kyphoscoliosis with associated paralysis or spasticity),
c. Patients having spondylolisthesis (i.e. Isthmic spondylolisthesis, degenerative spondylolisthesis and acute pars fracture allowing spondylolisthesis).
The Zodiac® Polyaxial Spinal Fixation System is intended for use as a posterior spinal fixation device to aid in the surgical correction of various spinal deformities and pathologies in the thoracolumbo-sacral iliac portion of the spine. It is intended to provide stabilization during the development of fusion utilizing a bone graft. Specific indications for the Zodiac® Polyaxial Spinal Fixation System are dependent in part on the configuration of the assembled device and the method of attachment to the spine.
This document, K093077, is for a medical device called the "Zodiac® Polyaxial Spinal Fixation System." It is a 510(k) submission, which means it seeks to demonstrate "substantial equivalence" to a legally marketed predicate device, rather than proving safety and effectiveness through extensive clinical trials. Therefore, the information provided focuses on comparative testing and engineering principles rather than clinical performance and diagnostic metrics typically associated with AI/ML devices.
Here's an analysis based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance:
The document doesn't provide specific numerical acceptance criteria or performance metrics in a table format that would typically be seen for AI/ML device studies (e.g., sensitivity, specificity thresholds). Instead, it relies on substantiating equivalence to predicate devices through mechanical and dynamic testing.
| Acceptance Criteria (Implied) | Reported Device Performance (Summary) |
|---|---|
| Mechanical and dynamic performance comparable to predicate devices. | Mechanical and dynamic testing was performed. The testing demonstrated that additional components are substantially equivalent to the predicate Zodiac® Polyaxial Spinal Fixation System device. It is similar in terms of general design, intended use, and technological characteristics to the predicate devices. |
2. Sample Size Used for the Test Set and Data Provenance:
The document describes mechanical and dynamic testing, not clinical testing with patient data. Therefore, the concept of a "test set" from patient data, its sample size, or data provenance (country of origin, retrospective/prospective) is not applicable here. The "test set" would refer to the physical samples of the device components subjected to laboratory testing. The specific number of samples for mechanical and dynamic testing is not provided in this summary.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Those Experts:
As this is mechanical testing for a spinal fixation system, there's no "ground truth" in the diagnostic sense established by medical experts for a test set. Ground truth for mechanical testing would be defined by engineering standards, material properties, and regulatory requirements, typically evaluated by mechanical engineers or similar technical experts specialized in medical device testing. The document does not specify the number or qualifications of individuals who designed or oversaw this mechanical testing.
4. Adjudication Method for the Test Set:
Not applicable. Adjudication methods (e.g., 2+1) are used to resolve disagreements among human readers or experts when establishing ground truth for clinical data. This document describes mechanical testing, which would involve standardized procedures and measurements, not human interpretation requiring adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done:
No, an MRMC comparative effectiveness study was not done. This type of study assesses how AI assistance impacts human reader performance and is relevant for diagnostic or interpretive AI/ML devices. The Zodiac® Polyaxial Spinal Fixation System is a physical implant, not a diagnostic tool requiring human interpretation supported by AI.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done:
Not applicable. "Standalone performance" refers to the performance of an algorithm without human intervention, which is relevant for AI/ML diagnostic tools. The Zodiac® Polyaxial Spinal Fixation System is a physical medical device.
7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.):
For the mechanical and dynamic testing, the "ground truth" is based on:
- Engineering Standards and Specifications: Performance parameters defined by recognized industry standards for spinal implants (e.g., ASTM, ISO standards, though not explicitly cited in this summary).
- Predicate Device Performance: The demonstrated performance of the legally marketed predicate devices (K033090, K042673, K051286, K071890). The new device components are shown to perform "substantially equivalent" to these established devices.
8. The Sample Size for the Training Set:
Not applicable. There is no "training set" in the context of an AI/ML algorithm for this physical medical device. The "training" for such a device would be its design and manufacturing processes, informed by engineering principles, material science, and prior device iterations.
9. How the Ground Truth for the Training Set Was Established:
Not applicable, as there is no AI/ML training set. The "ground truth" in the broader sense for the design and development of the device (if considering a "training equivalent") would be based on:
- Biomechanical requirements of the spine.
- Material properties and strength requirements for permanent implantation.
- Clinical experience and performance data of existing spinal fixation systems (the predicate devices).
- Regulatory guidelines and standards for spinal implants.
§ 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.