(29 days)
The KHEIRON® Spinal Fixation System, including patient specific K-ROD, is intended to provide immobilization and stabilization of spinal segments in skeletally mature patients as an adjunct to fusion in the following acute and chronic instabilities or deformities of thoracic, lumbar, and sacral spine: degenerative disc disease (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies), degenerative spondylolisthesis with objective evidence of neurological impairment, fracture, deformities or curvatures (i.e. scoliosis, kyphosis, and/or lordosis), spinal tumor, pseudarthrosis and failed previous fusion. When used for posterior, non-cervical, pedicle screw fixation in pediatric patients, the KHEIRON® System including patient specific K-ROD is indicated as an adjunct to fusion to treat progressive spinal deformities (i.e., scoliosis, kyphosis, or lordosis) including idiopathic scoliosis, and congenital scoliosis. Additionally, the KHEIRON® Spinal Fixation System including patient specific K-ROD is intended to treat pediatric patients diagnosed with spondylolisthesis/spondylolysis, fracture caused by tumor and/or trauma, pseudarthrosis, and/or failed previous fusion.
This system is intended to be used with autograft and/or allograft.
Pediatric pedicle screw fixation is limited to a posterior approach.
Patient specific K-ROD devices are compatible with Nu Vasive Reline System components that are compatible with ø5.5mm and/or ø6.0mm rods as well as screws ø4.5mm or larger and at least 25mm in length.
S.M.A.I.O.'s patient specific K-ROD is part of the 510(k) cleared KHEIRON® Spinal Fixation system (K211981) designed for stabilization and correction of chronic instability or deformity of the thoracic, lumbar, and sacral spine. The patient specific K-ROD is manufactured from Ti-6Al-4V ELI per ASTM F136 and is available in diameters of 5.5 and 6.0 mm.
The NuVasive Reline System is a 510(k) cleared pedicle screw system (K223181) that consists of a variety of screws, hooks, rods, lock screws, transverse connectors, rod-to-rod connectors, iliac connectors, and general instruments. Implant components are available in a variety of sizes and can be rigidly locked into a variety of different configurations to suit the individual pathology and anatomical conditions of the patient. The NuVasive Reline System is designed to provide immobilization and stabilization of spinal segments as an adjunct to fusion in the treatment of acute and chronic instabilities or deformities of the posterior thoracic, lumbar, and sacral spine. The NuVasive Reline System is also used to treat severe spondylolisthesis (Grades 3 and 4) of the L5-S1 vertebral joint in skeletally mature patients receiving fusion by autogenous bone graft.
The purpose of this Special 510(k) Device Modification is to extend indication of S.M.A.I.O.'s patient specific K-ROD (K211981) for use with the NuVasive Reline System (K223181).
This FDA 510(k) clearance document is for a medical device modification, not an AI/Software as a Medical Device (SaMD) product. Therefore, many of the requested elements for describing an AI study, such as acceptance criteria based on performance metrics (e.g., sensitivity, specificity), sample sizes for test/training sets, expert ground truth establishment, MRMC studies, or standalone algorithm performance, are not applicable to this submission.
This submission focuses on demonstrating the substantial equivalence of a physical medical device modification (compatibility of a patient-specific K-ROD with another spinal fixation system) through engineering analysis and mechanical testing.
However, I can extract information related to the "acceptance criteria" and the "study" in the context of this physical device's mechanical performance:
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria (Mechanical Performance) | Reported Device Performance (Findings from V&V Activities) |
|---|---|
| K-ROD used with NuVasive Reline System must demonstrate similar strength to the primary predicate K-ROD. | K-ROD used with the NuVasive Reline System has similar strength as the primary predicate K-ROD. |
| Must pass Static and dynamic ASTM F1717 tests. | Tests were performed specifically for K-RODs used with the NuVasive Reline System, with identical set-up and parameters as presented in K211981 (primary predicate's clearance). (Implied passing, as concluded to be substantially equivalent). |
| Must pass Static torsion ASTM F1717 tests. | Tests were performed (Implied passing). |
| Must pass Static axial gripping capacity ASTM F1798 tests. | Tests were performed (Implied passing). |
| Must pass Static torsional gripping capacity ASTM F1798 tests. | Tests were performed (Implied passing). |
| Compatibility of patient-specific K-ROD with NuVasive Reline System components compatible with ø5.5mm and/or ø6.0mm rods, and screws ø4.5mm or larger and at least 25mm in length. | The information presented...demonstrates that the KHEIRON® Spinal Fixation System, including patient specific K-ROD, is compatible with the NuVasive Reline System as described herein. |
| No new worst-case scenario created for the K-ROD used with the NuVasive Reline System relative to the primary predicate K-ROD and predicate NuVasive Reline System devices. | Engineering analysis comparing K-ROD and NuVasive Reline System's titanium alloy rods determined that a new worst-case was not created. |
2. Sample size used for the test set and the data provenance:
- Sample Size: Not explicitly stated as "sample size" in the context of a dataset for AI. For mechanical testing, a "sample size" would refer to the number of physical devices tested. This detail is not provided, but it would have been determined by the specific ASTM standards (F1717, F1798) and internal engineering justifications.
- Data Provenance: This relates to the mechanical testing and engineering analysis performed for the modification. The tests were performed as part of the "V&V activities" (Verification & Validation) by the manufacturer S.M.A.I.O. (France). The data is prospective in the sense that the tests were conducted specifically for this submission.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not Applicable. This is a physical device modification, not an AI/SaMD. "Ground truth" in this context would refer to established engineering principles, material science data, and the specifications of the predicate devices, which are handled by qualified engineers and technical personnel during the design and testing phases.
4. Adjudication method for the test set:
- Not Applicable. This is a physical device submission. Adjudication methods like 2+1 or 3+1 are used for evaluating discrepancies in human expert interpretation, typically in AI/imaging studies.
5. 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:
- Not Applicable. This is a physical device submission, not an AI/SaMD.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not Applicable. This device is a physical medical implant, not an algorithm.
7. The type of ground truth used:
- Engineering Standards and Predicate Device Specifications: The "ground truth" for this submission would be the established mechanical and material properties defined by ASTM standards (F136 for material, F1717 and F1798 for mechanical testing) and the known performance and characteristics of the legally marketed predicate devices (KHEIRON® Spinal Fixation System (K211981) and NuVasive Reline System (K223181)). The "acceptability" is based on meeting or demonstrating equivalence to these established benchmarks.
8. The sample size for the training set:
- Not Applicable. This is a physical device submission, not an AI/SaMD. There is no concept of a "training set" in this context.
9. How the ground truth for the training set was established:
- Not Applicable. See point 8.
§ 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.