(417 days)
Spinal inner fixation system is intended for posterior, non-cervical, pedicle fixation for the following indications: severe spondylolisthesis (grade 3 or 4) of the L5-S1 vertebrae; trauma (i.e. fracture or dislocation), spinal stenosis, curvatures (i.e. scoliosis, kyphosis, and/or lordosis); tumor; pseudoarthrosis; and failed previous fusion. The device is to be used in skeletally mature patients, and for stabilization and immobilization of the spine as an adjunct to fusion with bone graft. The levels of fixation are T8 - S1.
Spinal inner fixation system consists of a variety of shapes and sizes of pedicle screws, rods, hooks, transverse linking pole assembly, and connecting components (side, domino, and axial), which can be rigidly locked into a variety of configurations. These components are made of titanium alloy per ASTM F136.
This document is a 510(k) premarket notification for a medical device, the "Spinal Inner Fixation System." It focuses on demonstrating substantial equivalence to a predicate device rather than presenting a study proving that the device meets a specific set of acceptance criteria for diagnostic performance or treatment efficacy in the way an AI/ML device would.
Therefore, much of the requested information regarding acceptance criteria, device performance, sample sizes for test/training sets, expert ground truth adjudication, MRMC studies, and standalone performance for AI/ML systems is not applicable or present in this document.
However, I can extract the information relevant to the mechanical performance testing conducted for this orthopedic device.
Here's the breakdown of the available information:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state numerical acceptance criteria for mechanical tests. Instead, it compares the proposed device's performance to that of the predicate device within the context of the testing standard ASTM F1717. The acceptance is based on the results showing no statistically significant difference between the proposed device and the predicate device for various mechanical properties.
| Specification | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Static compression bending: yield load | Similar to predicate, no statistically significant difference | Similar, the testing results show no statistically significant difference between two samples groups |
| Static compression bending: stiffness | Similar to predicate, no statistically significant difference | Similar, the testing results show no statistically significant difference between two samples groups |
| Dynamic compression bending | Similar to predicate, no statistically significant difference | Similar, the testing results show no statistically significant difference between two samples groups |
| Static torsion: torque | Similar to predicate, no statistically significant difference | Similar, the testing results show no statistically significant difference between two samples groups |
| Static torsion: torsional stiffness | Similar to predicate, no statistically significant difference | Similar, the testing results show no statistically significant difference between two samples groups |
| Materials | Conforms to ASTM F136 (TiAl4V ELI) | Titanium alloy (TiAl4V ELI) which conforms to ASTM F136 |
| Biocompatibility | Conforms to ASTM F136 (TiAl4V ELI) | Titanium alloy (TiAl4V ELI) which conforms to ASTM F136 |
| Sterility | Provided as non-sterile, requires steam sterilization | Provided as non-sterile, needs steam sterilization prior to use |
| Dissociation testing of screw head | (Not explicitly stated, but assumed to meet design specs based on overall conclusion) | Performed (stated but no specific result given, implied satisfactory) |
2. Sample size used for the test set and the data provenance
The document refers to "two samples groups" for the mechanical testing, but the specific numerical sample sizes are not provided. The data provenance is testing conducted by the applicant, Changzhou Dingjian Medical Appliance Co., Ltd., likely in China, as it is the country of origin for the submitter. This is a bench test, not clinical data, so the concepts of retrospective or prospective data as typically applied to patient studies are not applicable.
3. 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)
This is not applicable as this is a mechanical testing study, not a study involving human interpretation or ground truth establishment by experts in the context of diagnostic performance.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
This is not applicable for mechanical testing.
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
This is not applicable as this is a mechanical orthopedic device, not an AI/ML diagnostic or assistive device.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done
This is not applicable as this is a mechanical orthopedic device.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
For mechanical testing, the "ground truth" or reference standard would be the established testing methodology and performance characteristics defined by the ASTM F1717 standard and the performance of the legally marketed predicate device. The comparison is made against the predicate device's measured performance in these standardized tests.
8. The sample size for the training set
This is not applicable as this is a mechanical testing study, not an AI/ML study involving a training set.
9. How the ground truth for the training set was established
This is not applicable as this is a mechanical testing study.
§ 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.