Computer aid designed digital targeting template of pedicle of vertebral arch for atlantoaxial nailing

Study Design. Instead of inserting the screw based only on surgical experience,computer-aided design (CAD) techniques were used to build a digital model for treating a three year old Chinese girl. Objective. To improve the safety of atlantoaxial pedicle screw fixation. Summary of Background Data. Due to the complex of anatomy and variations in the structure of the pedicle of the atlantoaxial vertebral arch, the vertebral artery and spinal cord can easily get damaged during the process of screw insertion, resulting in a poor prognosis. Methods. The CT image of a patient with an atlantoaxial instability was loaded into a computer programme for 3D reconstruction. The 3D passageway for atlantoaxial pedicle and atlantoaxial targeting template were designed. Results. Rapid prototyping of an atlantoaxial targeting template which aided atlantoaxial pedicle screw fixation. Conclusion. The safety and degree of accuracy of atlantoaxial pedicle screw fixation were improved by the targeting template.