(29 days)
The VIPER systems are intended to provide immobilization and stabilization of spinal segments in skeletally mature patients as an adjunct to fusion in the treatment of acute and chronic instabilities of deformities of the thoracic, lumbar, and sacral spine.
The VIPER System is intended for noncervical pedicle fixation and nonpedicle fixation for the following indications: degenerative disc disease (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies); spondylolisthesis; trauma(i.e., fracture or dislocation); spinal stenosis; curvatures (i.e., scoliosis, kyphosis, and/or lordosis); tumor, pseudoarthrosis; and failed previous fusion in skeletally mature patients.
When used in a percutaneous, posterior approach with MIS instrumentation, the VIPER Systems are intended for noncervical pedicle fixation and nonpedicle fixation for the following indications: degenerative disc disease (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies); spondylolisthesis; trauma(i.e., fracture or dislocation); spinal stenosis; curvatures (i.e., scoliosis, kyphosis, and/or lordosis); tumor, pseudoarthrosis; and failed previous fusion in skeletally mature patients.
The VIPER® System is a 5.5mm rod system offered in both stainless steels and titanium materials. The system consists of monoaxial screws. polyaxial screws. uni-planar screws, and extended tab implants. They are available in various geometries and sizes to accommodate patient anatomy.
Here's an analysis of the provided text regarding the acceptance criteria and the study proving the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
Acceptance Criteria (Implicit) | Reported Device Performance |
---|---|
Mechanical Equivalence/Safety: The modified VIPER System components must perform mechanically as safely and effectively as the predicate device. | "Performance data in the form of an engineering rationale that included Finite Element Analysis was conducted to prove there was no new worst case component for the proposed VIPER System's components contained in this notification." |
"Both the engineering rationale that included Finite Element Analysis and the Substantial Equivalence Justification demonstrate that the device is as safe, as effective, and performs as well as the predicate device." | |
Material Equivalence: The materials used in the modified device must be identical to the predicate device and suitable for implant. | "Manufactured from ASTM F 138 implant grade stainless steel, ASTM F 139 implant grade stainless steel, and ASTM F 136 implant grade titanium alloy." (Implicitly, these are the same as the predicate and acceptable.) |
Design/Technology Equivalence: The design and technology of the modified components should be identical to the predicate systems, except for the specified changes. | "The proposed modifications to the DePuy Spine VIPER® Systems are identical to predicate devices (K111571) except for the addition of fully threaded and partially threaded favored angle polyaxial screws in various sizes to the systems, which are outside the range of the currently cleared screw offerings. The design, materials, and technology remain identical to the predicate systems." |
Intended Use Equivalence: The modified device must have the same intended use and indications as the predicate device. | The "Indications For Use" statement is identical to the predicate device's intended use described in section H. The only change is the addition of new screw types within this existing intended use. |
2. Sample Size Used for the Test Set and Data Provenance
This information is not provided in the document. The performance data relied on Finite Element Analysis (FEA), which is a computational simulation method, not a test on physical samples in the traditional sense requiring a "test set" sample size or data provenance from a specific geographical region (country of origin). It's a predictive engineering analysis.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications
This information is not applicable/not provided. FEA uses engineering principles and material properties as its "ground truth" for simulation, not expert human interpretation of test data in the way a clinical study would. The analysis is performed by engineering professionals.
4. Adjudication Method for the Test Set
This information is not applicable/not provided. As FEA is a computational analysis, there is no "adjudication method" in the sense of reconciling human expert opinions on a test set. The results are derived directly from the simulation model.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study typically involves human readers interpreting medical images or data, which is not relevant to the engineering rationale and Finite Element Analysis performed for this device modification.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was Done
Yes, in essence, a "standalone" performance evaluation was done, though not a standalone algorithm in the typical AI sense. The Finite Element Analysis (FEA) is a computational method that stands alone in evaluating the mechanical performance based on engineering models, without human intervention in the execution of the mechanical test itself. The FEA itself is the "algorithm" that provides the performance data without a human-in-the-loop for the mechanical assessment.
7. The Type of Ground Truth Used
The ground truth used for the Finite Element Analysis (FEA) would be established engineering principles, material properties (e.g., strength, stiffness of ASTM F 138, F 139 stainless steel, and F 136 titanium alloy), and validated computational models (e.g., meshing, boundary conditions, load application matching physiological conditions). There is no expert consensus, pathology, or outcomes data used as ground truth for this type of mechanical equivalence study.
8. The Sample Size for the Training Set
This information is not applicable/not provided. FEA is a simulation method, not a machine learning algorithm that requires a "training set." The models are built based on design specifications and material properties.
9. How the Ground Truth for the Training Set was Established
This information is not applicable/not provided. As there is no training set in the machine learning sense, there's no ground truth established for it. The "ground truth" for the FEA itself (as explained in point 7) is based on established scientific and engineering principles.
§ 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.