RESUMO
BACKGROUND:Surgical accuracy is a key to surgical success.The traditional positioning method mainly depends on surgeons' experience,which is too subjective to cause screw misplacement.Three-dimensional (3D) printing technology-assisted pedicle screw placement can make individualized surgical scheme,most importantly,it is accurate and simple showing promising application prospect.OBJECTIVE:To design an individualized pedicle guide plate with 3D printing and to simulate screw placement in vitro,and to explore its feasibility in vertebral pedicle screw placement.METHODS:Lumbar spine CT data of 11 patients with degenerative lumbar spine were selected from April 2016 to July 2016 at Hebei General Hospital,and 3D reconstruction of L1,L3 and L5 vertebrae of each case was performed.Pre-experiment was conducted based on one patient's lumbar CT data:according to the principle of screw placement,the screw position and orientation were designed to prepare the best pedicle guide plate model.Afterwards,the screw placement in vitro was simulated,and was then cut by chainsaw to verify the accuracy of screw placement.RESULTS AND CONCLUSION:(1) A total of 30 pedicle guide plates were used,and 60 screws were inserted in the patients,and the placement process was successful.The guide plates adhered well,none appeared with screw perforating the pedicle cortex,and the screw position was accurate and reliable.(2) There were no significant changes in the transverse section and sagtial section angles of the left and right pedicle screws before and after placement (P ＞ 0.05).(3) These results suggest that the 3D-printed individualized pedicle guide plate holds a good accuracy of placement,which can be applied in the vertebral pedicle screw placement,but further clinical trials are needed.
