Application of Mimics and rapid prototyping in atlantoaxial pedicle placement / 中华创伤杂志

ABSTRACT

Objective To develop and validate a novel method of atlantoaxial pedicle screw placement by using three-dimensional reconstruction software Mimics and rapid prototyping. Methods Three-dimensional reconstruction of 20 CT scanned cadaver atlantoaxial specimens was performed by using Mimics and the parameters of the pedicles were measured. Then, physical model of the pedicles was manufactured by using rapid prototyping and the parameters of the cadaver pedicles were measured. The parameters of the atlantoaxial pedicle were directly measured. All the data were analyzed statistically to verify the accuracy of the reconstructed images and physical models. The optimal pedicle channel was found to design individual fixation parameters, based on which fixation of cadaver specimens was performed under direct guidance of physical model. The accuracy of fixation was assessed by CT scanning. Results There was no statistical difference in parameters of the reconstructed images, the physical model and the specimens, which could reflect accurate atlantoaxial anatomy. Postoperative CT scanning showed that the pedicle screws were inserted successfully in 16 sides of four specimens, except for one screw wearing medial bone cortex of the atlas artery. Conclusions Three-dimensional reconstruction of the atlantoaxial specimens by using Mimics and physical models made by rapid prototyping technology facilitate atlantoaxial pedicle screw placement and can enhance the accuracy of screw fixation.