Image-Based Planning and Validation of C1-C2 Transarticular Screw Fixation Using Personalized Drill Guides

Abstract

Objective: Posterior transarticular spine fusion is a surgical procedure used to stabilize the cervical bodies C1 and C2. Currently, spine screws are used most frequently, according to the procedure of Rllagerl. As the anatomy is rather complex and the view is limited, this procedure has a high risk factor. We present and validate a planning system for cervical screw insertion based on preoperative C T imaging.Materials and Methods: The planning system discussed allowed a neurosurgeon to interactively determine the desired position of the cervical screws, based on appropriate and real-time reslices through the preoperative C T image volume. From the planning, a personalized mechanical drill guide was derived as a means of transfemng the plan intraoperatively. Eight cadaver experiments were performed to validate this approach. Postoperative C T was applied, and screw locations were extracted from the postoperative images after registering them to preoperative images. In this way, the deviations of the axes of the planned and inserted screws were determined.Results: From an initial cadaver series, it was observed that the drill guides were not stable enough to cope with the drilling forces, and tended to become displaced. Still, most of the inserted screws were reported to be placed adequately. No vascular compromise or invasion of the spinal canal was observed. For a second cadaver series, the design of the drill guide was altered. In this series, the displacement was no longer present, and all screws were optimally placed.Conclusions: The preoperative planning system allowed the neurosurgeon to rehearse screw insertion in a way that is closer to surgical reality. The image-based validation technique allowed verification and enhancement of the template design on a cadaver study, giving accuracies comparable to those obtained with transfer by navigation. Comp Aid Surg 7:41-48 (ZOO?). @ O O~ WiIey-Liss, h c .

3D-Customized Guiding Template for Posterior Fixation in Complex Atlantoaxial Instability—Preliminary Experiences of National Cheng Kung University Hospital

“…As a new method of pedicle screw insertion, concept of personalized image-based guiding template in atlantoaxial fixation was first proposed by Van Cleynenbreugel et al in a cadaveric study. 7 With technology advancing, the cost of making a personalized template by 3D printing has dramatically decreased, and the 3D printing material is more durable and available than before. 3D guiding template has not only used in cervical spine but it has also been used in thoracic and lumbar spine.…”

“…[2][3][4][5][6] A novel way to perform atlantoaxial posterior fixation with three-dimensional (3D)-printed guiding template has been developed since 2002 in hope to decrease the risk of VA injury and increase precision in pedicle screws placement. 7 With the advance of 3D-printing technology, it becomes more available and affordable today. In recent years, many studies have proved guiding template for pedicle screw insertion has high accuracy and safety in lumbar and thoracic spine.…”

Deviation analysis of C2 translaminar screw placement assisted by a novel rapid prototyping drill template: a cadaveric study

“…Authors have designed different individual templates for C2 level screw placement, including pedicle, translaminar and Magerl screw placement [18,[27][28][29][30]. The keys to successful template design include precise fit, stability during drilling and practicality in the clinical setting.…”

An anatomical study comparing standard fluoroscopy and virtual fluoroscopy for the placement of C1–2 transarticular screws

“…Unfortunately, most CTbased image guidance techniques require intraoperative registration by identifying anatomical landmarks, which may lead to error during the registration process. 3,27,29 When using virtual fluoroscopy for C1-2 transarticular screw placement, one could theoretically attach the reference array (reference light-emitting diode frame) to the C-2 spinous process or to the Mayfield clamp. Although attachment to the C-2 spinous process should minimize the odds of movement between the clamp and the C-2 isthmus, placement of a bulky clamp on the spinous process of C-2 can crowd the operative field and obscure important anatomical landmarks.…”