(231 days)
The Posterior Lumber System Multi-Axial Screw DESCO is a posterior, nonpedicle screw system of the noncervical spine indicated for degenerative disc disease (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies), spondylolisthesis, fracture, tumor, pseudoarthrosis, and failed previous fusion.
The Posterior Lumbar System is a pedicle screw system 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: degenerative spondylolisthesis with objective evidence of neurological impairment, fracture, dislocation, scoliosis, kyphosis, spinal turnor, and failed previous fusion (pseudarthrosis).
The Posterior Lumbar System is a pedicle screw system indicated for the treatment of severe spondylolisthesis (Grades 3 and 4) of the L5-S1 vertebra in skeletally mature patients receiving fusion by autogenous bone graft having implants attached to the lumbar and sacral spine (L3 to Sacrum) with removal of the implants after the attainment of a solid fusion.
The crosslinks and rod-to-rod connectors are used to connect two rods in a pedicle screw construct. The purpose is to add further stability to the system. The components are made of medical grade, FDA recognized, titanium alloy (ASTM F316). The rigid crosslinks come in sizes ranging from 15mm to 48mm, in increments of 3mm, and the modular crosslinks come in 3 sizes (small 30-38mm, medium 37-52mm, and large 50-70mm), but can lock at any size in between the ranges. The variable flat crosslinks contain 2 components an SX (left) and DX (right). The two are connected by a nut that can lock the connector along any length: small 26.6-33.6mm, medium 36.6-53.6mm, and large 46.6-73.6mm. The cross-links are used to connect parallel constructs along the spinal column to stabilize the system. The rod-to-rod connectors come in domino form and longitudinal. The rod-to-rod connectors will connect two rods in series either along the same axis by utilizing the longitudinal connector or offset the rod laterally by approximately 5.5mm (the diameter of a rod) utilizing the domino connector. The crosslinks and rod-to-rod connectors utilize a nut which threads through the component and comes to contact with the rod to lock the component to the rod along the construct.
The provided document is a 510(k) summary for Sintea Plustek's Posterior Lumbar System, which describes a medical device, not a software device or an AI algorithm. Therefore, the questions related to AI/algorithm performance, ground truth establishment, expert consensus, and effects on human readers are not applicable.
The document primarily focuses on demonstrating the substantial equivalence of the modified device (adding cross-links and connectors) to its predicate device through mechanical testing.
Here's an analysis of the available information regarding acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criterion (Test Standard) | Device Performance |
|---|---|
| Static Compression (ASTM F1717) | New cross-link versions performed better than the previously cleared cross-link. The new version demonstrated greater stiffness, higher yield, and ultimate strength. |
| Static Torsion (ASTM F1717) | New cross-link versions performed better than the previously cleared cross-link. The new version demonstrated greater stiffness, higher yield, and ultimate strength. |
| Dynamic Compression/Fatigue (ASTM F1717) | New cross-link versions performed better than the previously cleared cross-link. The new version demonstrated greater stiffness, higher yield, and ultimate strength. |
| Static Compression (ASTM F1798) | Rod-to-rod connectors performed adequately. No direct comparison to predicate stated, but implied to be equivalent or better based on substantial equivalence claim. |
| Static Torsion (ASTM F1798) | Rod-to-rod connectors performed adequately. No direct comparison to predicate stated, but implied to be equivalent or better based on substantial equivalence claim. |
Note on "Acceptance Criteria": The document doesn't explicitly state quantitative acceptance criteria (e.g., "must withstand X N of force"). Instead, the primary acceptance criterion is achieving "substantial equivalence" to the predicate device, which is demonstrated by meeting or exceeding the predicate's mechanical performance in the specified ASTM tests. The statement "the new version obtained results demonstrating greater stiffness, and higher yield and ultimate strength" for the cross-links strongly implies that the new device met or exceeded the performance of the predicate, thus satisfying the substantial equivalence requirement for mechanical properties.
2. Sample Size Used for the Test Set and Data Provenance
- The document mentions "mechanical tests performed on the worst case crosslink construct" and "tests performed on the rod-to-rod connectors."
- Sample Size: The exact number of samples (e.g., how many cross-links or rod-to-rod connectors were tested for each configuration) is not specified in this 510(k) summary. For mechanical testing, sample sizes are typically small (e.g., 5-10 per test condition) but sufficient to demonstrate performance characteristics.
- Data Provenance: The tests are described as "mechanical tests," which are laboratory tests performed on physical medical device components. The data is generated from these controlled lab experiments, not from patient data or clinical studies. Therefore, there is no country of origin of patient data, nor is it retrospective or prospective in the clinical sense.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- Not Applicable. This is a physical medical device. Ground truth for its performance is established through standardized engineering mechanical tests (ASTM F1717, ASTM F1798), not through expert clinical consensus on patient data. The "ground truth" is the physical performance measured in a lab.
4. Adjudication Method for the Test Set
- Not Applicable. As this involves mechanical testing, there is no adjudication method in the human-reader sense. The test results are objective measurements from laboratory equipment.
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 medical device, not an AI or imaging diagnostic device. No human-in-the-loop performance or MRMC study was conducted.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not Applicable. This is a physical medical device. No algorithm or standalone software performance was evaluated.
7. The Type of Ground Truth Used
- The ground truth for this device's performance is established by objective measurements from standardized mechanical tests according to ASTM F1717 and ASTM F1798. These standards define the methodology for evaluating the mechanical properties (static compression, static torsion, dynamic compression/fatigue, stiffness, yield, ultimate strength) of spinal implant systems and intervertebral body fusion devices.
8. The Sample Size for the Training Set
- Not Applicable. There is no "training set" as this is not an AI/machine learning device. The design, development, and testing of this physical device are based on engineering principles and material science, not data training.
9. How the Ground Truth for the Training Set was Established
- Not Applicable. As there is no training set, this question is irrelevant.
Summary Conclusion:
The Sintea Plustek Posterior Lumbar System is a hardware medical device. Its acceptance criteria and performance are determined by demonstrating substantial equivalence to a predicate device through standardized biomechanical testing, not through clinical trials, expert interpretation of data, or AI algorithm performance metrics. The document clearly states that mechanical tests were performed according to ASTM F1717 and ASTM F1798, and that the new components (cross-links and rod-to-rod connectors) either performed better than the predicate's equivalent components or met the requirements for substantial equivalence.
§ 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.