(17 days)
The DYNAMIS™ Implant System is indicated for sacroiliac joint fusion for:
- Sacroiliac joint dysfunction including sacroiliac joint disruption and degenerative sacroiliitis.
- Augmenting immobilization and stabilization of the sacroiliac joint in skeletally mature patients undergoing sacropelvic fixation as part of a lumbar or thoracolumbar fusion.
The DYNAMIS™ Implant System is also indicated for fracture fixation of the pelvis, including acute, non-acute and nontraumatic fractures.
The DYNAMIS™ Implant System consists of threaded, fenestrated, cannulated, 3D-printed implants and associated instruments. The implants are constructed from medical grade titanium alloy (Ti-6Al-4V ELI per ASTM F3001). The implants are fully threaded with a lag design and a cannulated central threaded body. To accommodate varying patient anatomy, the DYNAMIS™ Implants are available in multiple diameters and length offerings. The implants allow for packing of autograft and allograft materials. Using the designated instrument system, two or more implants should be inserted across the SI Joint to apply a compressive force across the joint and to provide stabilization and fusion. The DYNAMIS™ implants are single use devices that are provided sterile. The DYNAMIS™ Implant System is comprised of DYNAMIS™ Screws and DYNAMIS™ TRU-NANO Screws.
DYNAMIS™ TRU-NANO Screws: The surfaces of the DYNAMIS™ TRU-NANO Screws incorporate a micro- and nano-roughened surface that demonstrates the requirements for nanotechnology. The surface of the screws have been deliberately manipulated to produce nanoscale dimensions which exhibit specific properties. These screws are electrochemically treated to possess a controlled nanotopography composed of nanotube arrays having a pore size diameter between 30-97 nanometers. Calcium and phosphate are incorporated into the nanotube surface.
This document describes the DYNAMIS™ Implant System, a medical device for sacroiliac joint fusion and pelvic fracture fixation. The FDA 510(k) clearance letter determines the device to be substantially equivalent to legally marketed predicate devices.
However, the provided text does not contain acceptance criteria for device performance or a detailed study description proving that the device meets those criteria, as typically found in a clinical study report or a more comprehensive technical document.
Instead, the performance data section mentions:
- Testing per ASTM standards:
- Static cantilever bending and dynamic cantilever bending (ASTM F3574)
- Static axial pullout, static torsion, and driving torque (ASTM F543)
- In vitro evaluations for nanotechnology: Quantitated mineralization of extracellular matrix by osteoblasts (OB) and mesenchymal stem cells (MSC) on titanium alloy surfaces.
- Bacterial endotoxin testing: In accordance with AAMI ST72:2011.
The statement reads: "The results demonstrate that the DYNAMIS™ Implant System is substantially equivalent to the predicate devices." and "in vitro study results demonstrated that the DYNAMIS™ TRU-NANO Screw nanosurface develops statistically significantly greater mineralization in both osteoblast and mesenchymal stem cell cultures compared to other surfaces."
Without further information, I cannot provide the specific details requested in your prompt regarding acceptance criteria, sample sizes, ground truth establishment, expert qualifications, or MRMC studies. The provided document is a regulatory clearance letter, which summarizes the basis for clearance, but does not include the detailed technical study reports.
Thus, I can only provide the information that is present in your input.
Based on the provided FDA 510(k) clearance letter (K251075) for the DYNAMIS™ Implant System, the following information can be extracted:
1. Table of Acceptance Criteria and Reported Device Performance
The provided document does not explicitly list specific numerical acceptance criteria for the mechanical tests. Instead, it states that the performance testing results "demonstrate that the DYNAMIS™ Implant System is substantially equivalent to the predicate devices." For the nanotechnology aspect, the acceptance criterion implicitly relates to superior mineralization.
| Test Category | Specific Test (Standard) | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|---|
| Mechanical Testing | Static cantilever bending (ASTM F3574) | Performance comparable/equivalent to predicate devices. | "The results demonstrate that the DYNAMIS™ Implant System is substantially equivalent to the predicate devices." |
| Dynamic cantilever bending (ASTM F3574) | Performance comparable/equivalent to predicate devices. | "The results demonstrate that the DYNAMIS™ Implant System is substantially equivalent to the predicate devices." | |
| Static axial pullout (ASTM F543) | Performance comparable/equivalent to predicate devices. | "The results demonstrate that the DYNAMIS™ Implant System is substantially equivalent to the predicate devices." | |
| Static torsion (ASTM F543) | Performance comparable/equivalent to predicate devices. | "The results demonstrate that the DYNAMIS™ Implant System is substantially equivalent to the predicate devices." | |
| Driving torque (ASTM F543) | Performance comparable/equivalent to predicate devices. | "The results demonstrate that the DYNAMIS™ Implant System is substantially equivalent to the predicate devices." | |
| Biological Testing | Nanotechnology - Cell Mineralization (In vitro) | Statistically significantly greater mineralization. | "in vitro study results demonstrated that the DYNAMIS™ TRU-NANO Screw nanosurface develops statistically significantly greater mineralization in both osteoblast and mesenchymal stem cell cultures compared to other surfaces." (compared to "other surfaces" - likely meaning unsuffaced titanium or the non-nano predicate) |
| Sterility Testing | Bacterial endotoxin testing (AAMI ST72:2011) | Meet specified testing limit. | "Bacterial endotoxin testing was conducted in accordance with AAMI ST72:2011 and met the specified testing limit." |
2. Sample Size Used for the Test Set and Data Provenance
The document does not specify the sample sizes for any of the tests (mechanical, in vitro, or endotoxin).
Regarding data provenance:
- The mechanical and biological testing appears to be laboratory-based performance testing on the device itself and its components.
- The document implies the tests were conducted by the manufacturer or a contracted lab for regulatory submission.
- There is no mention of patient data (e.g., country of origin, retrospective/prospective clinical data) as this device is not an AI/imaging device. The testing is for the physical device's performance.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This information is not applicable or not provided in the context of the described device testing.
- For mechanical tests, the "ground truth" is derived from engineering standards (ASTM) and predicate device performance. No human experts are typically involved in establishing "ground truth" for these tests in the way they would for medical image interpretation or clinical outcomes.
- For in vitro biological tests, expert understanding of cell biology and statistical analysis is involved, but not in the sense of adjudicating a "ground truth" from a test set of patient cases.
4. Adjudication Method for the Test Set
This information is not applicable or not provided as there is no human interpretation or consensus process described for the test results. The tests are laboratory-based and yield objective measurements compared against standards or predicate devices.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, and effect size
No, an MRMC comparative effectiveness study was not done. This type of study is relevant for diagnostic imaging or AI-assisted interpretation devices to assess human reader performance with and without AI. The DYNAMIS™ Implant System is a physical orthopedic implant, not a diagnostic or AI software.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done
This information is not applicable. The DYNAMIS™ Implant System is a physical medical implant, not an algorithm or AI software, so the concept of "standalone performance" for an algorithm does not apply.
7. The Type of Ground Truth Used
The "ground truth" for the performance claims appears to be:
- Engineering Standards: For mechanical tests, adherence to and performance relative to ASTM F3574 and ASTM F543 requirements.
- Predicate Device Performance: Comparative performance against the DYNAMIS™ SI Screw System (K243565) and Nanovis Nano FortiFix (K193211) for mechanical properties.
- Biological Activity (Quantitative Measurement): For the nanosurface, quantifiable measurements of secreted extracellular matrix mineralization by specific cell types (osteoblasts and mesenchymal stem cells) in an in vitro laboratory setting.
- Regulatory Standards: For bacterial endotoxin testing, compliance with AAMI ST72:2011.
8. The Sample Size for the Training Set
This information is not applicable or not provided. "Training set" refers to data used to train machine learning models. This device is a physical implant, not an AI or software device that requires a training set.
9. How the Ground Truth for the Training Set was Established
This information is not applicable. As established above, there is no mention of an AI/ML component or a "training set" for this physical device.
§ 888.3040 Smooth or threaded metallic bone fixation fastener.
(a)
Identification. A smooth or threaded metallic bone fixation fastener is a device intended to be implanted that consists of a stiff wire segment or rod made of alloys, such as cobalt-chromium-molybdenum and stainless steel, and that may be smooth on the outside, fully or partially threaded, straight or U-shaped; and may be either blunt pointed, sharp pointed, or have a formed, slotted head on the end. It may be used for fixation of bone fractures, for bone reconstructions, as a guide pin for insertion of other implants, or it may be implanted through the skin so that a pulling force (traction) may be applied to the skeletal system.(b)
Classification. Class II.