Application of the life-size patient-specific three-dimensional cervical spine anatomical model for odontoid fracture fixation

Abstract

Objective: Cervical fixation is the most common treatment of vertebral fractures, osteosarcoma, osteomyelitis, arthritis, and congenital disorders. Mortal complications, such as internal carotid artery, vertebral artery (VA), and spinal cord damages, may occur during the application. The aim of this study was to create the application of the actual three-dimensional (3D) personalized model which was exercised for screwing insertion in C2 damage patients. Methods: Two patients with Type II of C2 fractures were treated with personalized spine models. These models were investigated to achieve particular information of non- and bony elements such as the highness, thickness, and the field of pedicles and vascular diameters for an intraoperative reference. The model was to determine the probable variations and to observe the success of screw rate in the treatment of C2 fractures. The operation duration, instrumentation time, blood loss volume, and clinical and radiological assessment were done. The 3D model's perception was evaluated. Results: Cervical models were defined to secure intervention areas of the VA pedicles and screws. Neither vascular nor neurologic damages were happened in all cases. Besides, the cases did not include broken nails, screw pullout, fracture of bone structure, or infection. Cervical models demonstrated (1) examination of the VA pattern, (2) valuation of virtual screw trajectory line before screw fixation, (3) the application of prebent rods during procedure to contribute to the safety of the posterior instrumentation, (4) postsurgical confirmation, and (5) examined movements of the neck postoperatively. The perception of 3D model for treating C2 fracture was thereby diminishing surgical time, bleeding amount and operative complications. Survey perception of model was calculated in statistical significance (P < 0.05). Conclusion: Personalized model is active and confident in achieving an accurate and safe screw fixation during surgery, especially in anatomically abnormal cases. Cervical model provides an accurate representation of the fracture location, pedicle size, and VA shapes. It is therefore useful in surgical planning as it maximizes the possibility of ideal screw position, as well as providing individualized information concerning cervical spinal anatomy.

Keywords

• individualized screw insertion
• odontoid fracture
• patient-specific model
• preoperative planning
• vertebral artery