Application Study Of Mimics And Rapid Prototyping In Individual Dynesys Pedicle Placement

Objective To design a novel method of individual Dynesys pedicle placement,and to explore the clinical value and significance of Mimics and rapid prototyping using in individual Dynesys pedicle placement.Materials and methods Collection 16 cases of normal adult lumbar specimens, with L4 and L5 for target segment,dissect the specimens and collect CT image date.16 three dimensional images were reconstructed by using Mimics, and then the data was exported in STL+ format.Using rapid prototyping to manufacture all of the physical models.Measure pedicle parameters of anatomical specimens, 3D images and physical models with vernier caliper,protractor and Mimics software,and then analyse the accuracy of 3D images and physical models. Design the optional pedicle channel in Mimics,and fix 1-16 lumbar specimens with Dynesys pedicle screws according to the direct guidance of physical models.The accuracy of fixation was assessed by CT scanning.Results There was no statistical differences in the pedicles data between anatomical specimens and 3D images(P>0.05),and so as the pedicles data between anatomical specimens and physical models(P>0.05). The 3D images and physical models can accurately reflect the anatomical configuration of lumbar anatomical specimens. 64 pedicle screws were inserted in 32 anatomical lumbar vertebrae,only 1 breached the pedicle cortical. Nailing accuracy is 98.44%(63/64).Conclusion Mimics software can reconstruct three-dimensional images of lumbar vertebrae,and set individualized parameters.The Dynesys pedicle screw placement will be safer with the help of Mimics and physical models.