Search Results

The CerviFix System is intended to provide stabilization to promote fusion of the cervical spine and occipital-cervical junction (occiput – T3) for the following indications:

• DDD (neck pain of discogenic origin with degeneration of the disc as confirmed by . patient history and radiographic studies)
• spondylolisthesis ●
• spinal stenosis .
• fracture/dislocation .
• atlanto-axial fracture with instability .
• occipital-cervical dislocation .
• revision of previous cervical spine surgery .
• . tumors

The screws are limited to occipital fixation only.

The CerviFix System can also be linked to the Synthes Posterior Universal Spine System using the 3.5/6.0mm parallel connectors from that system.

SYNTHES Spine CerviFix System consisting of rods, plate/rods, hooks, bone screws, parallel connectors and set screws. These components are manufactured from the titanium alloy TiAlNb (ASTM F1295). The bone screws are composed of commercially pure grade 4 Titanium (ASTM F67).

The rods are 3.5mm in diameter and are offered in four lengths, 80, 120, 240 and 300mm. The plate/rod is a 3.5 mm or 6.0 mm diameter rod that transitions into a 3.5mm reconstruction plate at the opposite end. Hooks are available in both a left and right configuration to allow bilateral placement of the hook/rod or plate/rod/hook construct. The occipital bone screws are provided in the following configurations: a 3.2mm cortex screw, a 3.5mm cancellous screw, or a 4.0mm cancellous screw.

The device functions as follows: For non occipitocervical fusion, the end of the rod, cut to an appropriate length, is inserted into the rod opening of the hooks and loosely tightened into position with the set screws included in the hooks. The construct is then positioned under the laminae of the spinal seaments to be instrumented. Once the construct is compressed together, the set screws are locked down to the rod. For occipitocervical fusion, the plate/rod is bent and cut to an appropriate length. The plate portion of the implant is fixed to the occiput with screws and the rod portion is attached to the cervical spine with hooks. Hooks are available in both right and left opening configurations to allow bilateral placement of the hook/rod construct.

The construct can also be linked to the 6.0mm diameter rods of the Universal Spine System (USS) using 3.5mm/6.0mm parallel connectors.

Here's an analysis of the provided text regarding the Synthes CerviFix System, focusing on acceptance criteria and the study that proves its performance:

1. A table of acceptance criteria and the reported device performance

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

This submission relies on mechanical testing of the device components, not clinical data involving human or animal subjects. Therefore, traditional "sample size for a test set" and "data provenance" (country of origin, retrospective/prospective) as understood in clinical studies are not applicable. The "test set" here refers to the collection of physical implant components subjected to mechanical tests. The document does not specify the number of components tested.

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 a mechanical performance study, not a clinical study requiring expert assessment of medical imaging or patient outcomes. Therefore, the concept of "experts establishing ground truth for a test set" with qualifications like "radiologist with 10 years of experience" is not relevant. The ground truth for mechanical performance is established by the ASTM F1717 standard itself, which defines acceptable performance parameters. The experts involved would be engineers and testing personnel experienced in applying this standard.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

There is no adjudication method described for a clinical test set in this document, as it focuses on mechanical testing. The evaluation of mechanical test results against the ASTM standard would typically involve internal quality control and verification procedures by the manufacturer and, ultimately, FDA review of the submitted data for compliance with the standard.

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

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This document describes a new medical device (spinal fixation system) and its mechanical performance, not an AI-powered diagnostic tool requiring human reader studies. Therefore, discussing the effect size of human readers improving with or without AI assistance is not applicable.

6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done

No standalone (algorithm only) performance study was done. Again, this is a mechanical medical device, not an algorithm or AI system.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)

The "ground truth" for this device's performance is based on engineering standards and established mechanical properties. Specifically:

• ASTM standard F1717: This standard defines the methodologies and acceptance criteria for static and fatigue performance characteristics of metallic spinal plate systems, which the CerviFix System falls under.
• Material properties: The use of specific titanium alloys (TiAlNb and commercially pure grade 4 Titanium) as defined by ASTM F1295 and ASTM F67, respectively, is a "ground truth" for material composition and strength.
• Predicate device similarity: The "ground truth" for substantial equivalence relies on demonstrating that the new device's material, methods of use, and instrumentation are sufficiently similar to already cleared predicate devices.

8. The sample size for the training set

Not applicable. This submission doesn't involve machine learning or AI, so there is no "training set."

9. How the ground truth for the training set was established

Not applicable. As there is no training set, the establishment of ground truth for one is irrelevant.

Summary of the Study Proving Acceptance Criteria:

The study proving the device meets its acceptance criteria is a mechanical testing study performed in accordance with ASTM standard F1717.

• Objective: To document the static and fatigue performance characteristics of the Synthes CerviFix System.
• Methodology: Mechanical tests were conducted following the procedures outlined in ASTM F1717.
• Results/Conclusion: The testing "demonstrated that the performance characteristics satisfy the requirements of posterior occipitocervical and upper thoracic (Occiput-T3) fixation."
• Additional Evidence for Substantial Equivalence: The document also highlights the identical material composition to numerous previously cleared Synthes Spinal products and the similar methods for use and instrumentation to predicate devices (Synthes CerviFix and Occipital-Cervical Plate/Rod and Hook systems). This combination of mechanical performance against a recognized standard and demonstrated similarity to predicate devices forms the basis for the FDA's finding of substantial equivalence.

Ask a specific question about this device