(452 days)
"Paonan" Armstrong Posterior System is intended to provide immobilization and stabilization of spinal segments in skeletally mature patients as an adjunct to fusion using autograft. This system is intended for posterior, non-cervical pedicle fixation of the thoracic, lumbar, and sacraliliac spine (T1-Sacrum/Tium) for the following indications:
- Degenerative disc diseases (DDD) (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies) degeneration of the disc confirmed by history and radies)
- Degenerative Spondylolisthesis with objective evidence of neurologic impairment.
- Fractures
- Dislocation
- Scoliosis
- Kyphosis
- Spinal tumor
- Failed previous fusion (pseudarthrosis)
"Paonan" Armstrong Posterior Spinal Fixation System includes pedicle screws, rods, cross connectors, and associated instruments. Different types or sizes of these implants are available so that adaptations can be utilized to take into account the unique pathology of individual patients. The system components are manufactured from Ti6Al4V based which complies with ASTM F136 /ISO 5832-3.
The document describes the "Paonan" Armstrong Posterior Spinal Fixation System, a medical device for spinal immobilization and stabilization. It outlines the acceptance criteria and the study performed to demonstrate its substantial equivalence to a predicate device, as required for 510(k) clearance by the FDA.
Here's the breakdown of the requested information:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (referencing ASTM F1717 & F1798) | Reported Device Performance |
|---|---|
| Mechanical Testing per ASTM F1717: |
- Static Compression Bending Test
- Dynamic Compression Bending Test
- Static Torsional Test (for spinal construct) | Performed, demonstrating "satisfactory mechanical performance" (implied as being equivalent to the predicate, though specific numerical results are not provided in this summary). The summary states, "The results demonstrate substantial equivalence of the 'Paonan' Armstrong Posterior Fixation System to the predicate device." |
| Mechanical Testing per ASTM F1798: - Axial Gripping Capacity Test
- Torsional Gripping Capacity Test (of Cross Link and Connecting Block interconnection mechanism) | Performed, demonstrating "satisfactory mechanical performance" (implied as being equivalent to the predicate). The summary states, "The results demonstrate substantial equivalence of the 'Paonan' Armstrong Posterior Fixation System to the predicate device." |
2. Sample Size Used for the Test Set and Data Provenance
The document discusses mechanical testing of the device components, not clinical data from patients. Therefore, the concepts of "test set sample size" and "data provenance (country of origin, retrospective/prospective)" as they relate to human subjects or retrospective/prospective studies are not applicable in this context. The study performed involves laboratory-based mechanical tests of the physical device components.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Experts
This is not applicable. The "ground truth" for mechanical testing is established by engineering standards (e.g., ASTM F1717, ASTM F1798) and the performance of the predicate device, not by expert human interpretation of images or patient data. The evaluation is based on objective measurements and comparison to defined metrics derived from the standards and predicate.
4. Adjudication Method for the Test Set
This is not applicable. As the study involves mechanical testing against engineering standards, there is no human adjudication process involved in establishing test results or "ground truth." Results are determined by measurement and comparison to predefined criteria.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
This is not applicable. An MRMC study pertains to the evaluation of diagnostic devices that rely on human interpretation of images or data, often comparing AI performance with and without human assistance. This document describes mechanical testing of a spinal fixation system, not a diagnostic AI device.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done
This is not applicable. The device is a physical spinal fixation system, not a software algorithm or AI.
7. The Type of Ground Truth Used
The "ground truth" for this device's mechanical performance is defined by:
- Established engineering standards: Specifically ASTM F1717 (for static/dynamic compression bending and static torsion of spinal constructs) and ASTM F1798 (for axial and torsional gripping capacity).
- Predicate device performance: The "Paonan" Armstrong Posterior Spinal Fixation System's performance was compared to the predicate system (MYKRES Spinal System, K051704) to demonstrate substantial equivalence.
8. The Sample Size for the Training Set
This is not applicable. This device is a physical implant, not an AI or machine learning model that requires a training set.
9. How the Ground Truth for the Training Set Was Established
This is not applicable for the reasons stated in 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.