(361 days)
The Posterior Spinal Fixation System is intended for posterior, non-cervical fixation as an adjunct to fusion 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; pseudarthrosis; and/or failed previous fusion.
The Posterior Spinal Fixation System is a single-use system for surgical fixation of the spine. It is made up of pedicle screws, rods, and interconnecting devices. The implanted parts confer stabilization and fusion of two or more spinal segments and are to be removed once their stabilizing function is no longer required. The implantable devices are manufactured from titanium alloy and are provided non-sterile.
The Posterior Spinal Fixation System includes the following sets:
RS8 LEGEND (designed for open surgery) RS8 LONG (designed for minimally invasive surgery)
Each set comprises of different rods, screws, set screws, and accessory parts, including various lengths and diameters of reduction screws. Both sets are designed for internal posterior thoracolumbar fixation of the spine. Patient diagnosis and individual conditions should be taken into consideration when selecting the surgical option.
The provided text describes a 510(k) premarket notification for a Posterior Spinal Fixation System, which is a medical device, not an AI/ML device. Therefore, the questions regarding acceptance criteria, study design for AI/ML performance, ground truth establishment, and training/test set sample sizes for an AI/ML model are not applicable here.
The document focuses on demonstrating substantial equivalence to a previously cleared predicate device, Medtronic Sofamor Danek USA, Inc.'s CD HORIZON® Spinal System (K130646). The acceptance criteria are implicit in the comparison to the predicate device and relevant standards.
Here's a breakdown of the relevant information provided:
1. Table of Acceptance Criteria and Reported Device Performance (as applicable for a medical device):
The acceptance criteria are generally that the subject device performs comparably to the predicate device and meets applicable industry standards. The performance is assessed through bench testing and material characterization.
| Acceptance Criteria Category | Specific Criteria (Implicitly based on predicate equivalence and standards) | Reported Device Performance (Comparison to Predicate) |
|---|---|---|
| Intended Use | Identical to predicate device | Identical to predicate device: posterior, non-cervical fixation as an adjunct to fusion for specified indications. |
| Material Composition | Biocompatibility and mechanical properties comparable to predicate or compliant with standards. | Made of Titanium alloy (Ti-6Al-4V). Predicate uses stainless steel, titanium, titanium alloy, cobalt-chromium-molybdenum alloy, PEEK, and/or nitinol. Biocompatibility tested per ISO 10993 series. Material characterization per ASTM and GB/T standards. |
| Mechanical Performance (Bench Testing) | Comparable static and dynamic mechanical properties to the predicate, meeting relevant ASTM standards for spinal implant constructs. | - Static Compression: Compressive bending yield load lower than predicate; compressive bending ultimate load higher than predicate. |
- Dynamic Compression: Experienced more fractures than predicate.
- Static Tensile: Tensile bending ultimate load lower than predicate.
- Static Torsion: Yield torque and torsional stiffness lower than predicate.
(Note: Despite some lower values, the conclusion states these differences do not raise new questions of safety and effectiveness, implying overall equivalence or acceptable performance within design limits.) |
| Sterilization | Provided non-sterile with validated cleaning and sterilization instructions. | Provided non-sterile; validated manual cleaning and steam sterilization instructions provided. (Same as predicate.) |
| Surgical Instrument Materials | Acceptable materials for surgical use. | Stainless steel (17-4 PH), Silica gel, Polyformaldehyde (POM), Aluminum alloy. (Predicate materials unknown for comparison). |
| Physical Dimensions (e.g., rods, screws) | Dimensions comparable to predicate device to ensure interchangeability or functional equivalence where applicable. | Rods: Subject: 5.5-6.0mm diameter. Predicate: 3.5-6.0mm diameter.
Set Screws: Subject: 9.5-10mm diameter. Predicate: 6.0-10mm diameter.
Crosslinks: Subject: 5.0-6.0mm diameter, 23-80mm length. Predicate: 3.5-6.0mm diameter, 13-120mm length.
Polyaxial Reduction Screws: Subject: 4.5-7.5mm diameter, 25-90mm length. Predicate: 4.0-8.5mm diameter, 20-115mm length.
MISS Polyaxial Reduction Screws: Subject: 4.5-10mm diameter, 25-110mm length. Predicate: 4.0-8.5mm diameter, 20-115mm length. |
| MR Safety and Compatibility | Not explicitly stated as a criterion for the subject device. | Not evaluated for the subject device. Predicate is MR conditional. |
Study Proving Acceptance Criteria:
The device's acceptance is proven through non-clinical bench testing and adherence to recognized consensus standards for material characterization and biocompatibility, as compared to a legally marketed predicate device. The study aims to demonstrate substantial equivalence, not superior or absolute performance against new criteria.
2. Sample size used for the test set and the data provenance: Not applicable. This is a medical device, and the testing involved bench studies rather than testing on human or animal data sets for AI/ML performance evaluation. The provenance would be the test conditions and materials used in the lab.
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): Not applicable. "Ground truth" in the context of an AI/ML device for diagnostic or prognostic purposes is not relevant here. The "truth" for this device is its mechanical properties, material composition, and biocompatibility as determined by standardized physical and chemical tests.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set: Not applicable. There is no expert adjudication for bench testing of a physical medical device. The results are quantitative measurements against predefined standards or comparative measurements against the predicate device.
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 not an AI/ML device.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: Not applicable. This is not an AI/ML device.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.): The "ground truth" for this device is established through:
- Physical and Chemical Standards: ASTM, ISO, and GB/T standards for material properties, mechanical strength, and biocompatibility.
- Predicate Device Comparison: The performance and characteristics of the legally marketed predicate device (CD HORIZON® Spinal System) serve as a de facto "ground truth" for demonstrating substantial equivalence.
8. The sample size for the training set: Not applicable. This is not an AI/ML device. The device itself is manufactured, and its properties are tested.
9. How the ground truth for the training set was established: Not applicable. This is not an AI/ML device.
§ 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.