DEVICE SUPPORT
THE PRECISION SCREW

About the Device

The Precision Screw is an implantable grade metallic bone screw designed to be implanted into cortical bone of vertebrae. This provides physicians with a tool to assist in the electromagnetic tracking of instruments with respect to pre-acquired or real-time image data.

To suit a wide breadth of use cases, the Precision Screw is available in 2 sizes which includes straight or tapered thread variant and is supplied sterile. The Precision Screw is MR safe.

Instructions for use

Please refer to the following PDF document for information and Instructions regarding the correct use of The Precision Screw

INSTRUCTIONS FOR USE

Frequently Asked Questions - The Precision Screw

How long is it?

The screw comes in two lengths; CRY01-H4-1E is 6.3mm and CRY01-H3-1E is 5mm.

Can it stay in?

No. The screw is not a permanent implant.

Where should I put it?

Cortical bone of the vertebrae. The Precision Screw should not be placed in the lamina where there is risk of traversing the lamina and perforating the dura (durotomy) which may lead to loss of cerebral spinal fluid. Examples of appropriate parts of the vertebra to receive the Precision Screw are the Transverse Process, the Spinous Process and the Lamina where it is sufficiently thick (screw length plus 1mm).

How many should I use?

The Precision screw should be used wherever confirmation of navigation accuracy is required. Typically, every second level after the level of the reference array attachment.

What material is it?

Medical Grade Titanium Alloy.

Is it sterile?

Yes.

Will it work with all Nav Systems?

The Precision Screw will provide a fixed reference point for images produced with CT and O-Arm imaging techniques. Navigational Systems using these imaging technologies must be selected. An example of such a device is the Medtronic O-Arm Mobile CVT Device using the Medtronic Stealth Equipment and Software.

Where should I use the H3?

The H3 is used for smaller bones, especially cervical, and for harder bones.

Where should I use the H4?

This is used in lumbar vertebrae and where the bone quality is poor.

How do I put it on the driver?

Screws should be loaded onto the Driver by using the Screw Tray. The Screws are placed into the appropriate holding positions (the holes with the recessed gutter around) on the Screw Tray. Align the Driver over the head of the Screw, and firmly push down while twisting the driver until Screw feels secure in the Driver. Lift the Screw with the Driver up from the Tray, and confirm Screw remains engaged to Driver. If the Screw falls out, place the Driver into the appropriate checking hole, and push down, crimping the driver to the correct dimension. Then repeat process, and if Screw still falls off bone wax can be used sparingly to hold the screw in place.

How do I remove it at the end of the case?

When removing the Screw, relocate the Driver over the head, and turn the Driver anti-clockwise while gently pushing down until it engages. Then continue counter-clockwise turning of the driver until the Screw is free of bone and soft tissue. Confirm that the Screw is in the Driver when it has been removed from the patient.

Is the Screw reusable?

No. The Precision Screw is supplied sterile and is single use. It is not to be re-sterilised.