Comparative study of the accuracy of children cervical pedicle screw placement between personalized navigational template and free hand placement

English Keywords:Cervical  Pedicle  Digital  Personalized navigational template  Children

English Abstract:

  【Abstract】 Objectives: To explore the feasibility and accuracy of personalized navigational template in children cervical pedicle screw placement and compare it with free hand pedicle screw placement. Methods: 4 children(2 boys and 2 girls) corpses were randomly divided into two groups, with the range of age of 6-9 years old. Patients in group A underwent free hand pedicle screw placement, while group B underwent personalized navigational template, according to pre-operative CT results, the personalized navigational template was established by reverse engineering and rapid prototyping, then the template was referenced to pedicle screw implantation. Subsequently, CT scan was performed to evaluate the screw orientation and accuration. Results: A total of 28 pedicle screws was implanted in group A, 4 pedicle screws were implanted in C1, 3 screws showed no critical breaches and 1 screw showed critical breaches; 4 pedicle screws were implanted in C2, 2 screws were placed entirely within the pedicle and 2 screws showed no critical breaches; 20 pedicle screws were implanted into the lower cervical spine pedicle, 9 screws were entirely within the pedicle, 5 screws showed no critical breaches and 6 screws showed critical breaches. A total of 28 pedicle screws was implanted in group B, 4 pedicle screws were implanted into the atlas, 2 screws showed no critical breaches and 2 screws showed critical breaches; 4 pedicle screws were implanted in C2, 3 screws were entirely within the pedicle and 1 screw showed no critical breaches; 20 pedicle screws were implanted int lower cervical spine pedicle, 16 screws were entirely within the pedicle, 3 screws showed no critical breaches and 1 screw showed critical breaches. Due to the limited samples, the success and excellent rate of screw placement in upper cervical spine showed no difference between two groups, while showed significant difference(P＜0.05) in lower cervical spine between two groups. Conclusions: Children lower cervical spine pedicle screw placement assisted by personalized navigational template is highly accurate and simple.