P122. 3D printing technique in the surgery planning of C1-2 dislocation combined with and basilar invagination and occipitalization

Abstract

BACKGROUND CONTEXT Surgery planning of the C1-2 dislocation with and basilar invagination and occipitalization has changed significantly with the advent of 3D virtual techniques. However, it is still limited by its dependence on computer workstations, its lack of tactile experience and the inability to simulate surgical procedures and interventions. Recently the rapid prototyping or so called 3D printing technology could solve these problems. PURPOSE To introduce the technique of 3D printing model to surgically plan the C1-2 dislocation with and basilar invagination and occipitalization. STUDY DESIGN/SETTING This was a prospective observational study From January 2015 to December 2016. PATIENT SAMPLE A total of 24 cases undertook 3D printing modes at our institution. OUTCOME MEASURES The bone and model measurement of the width of C2 pedicle were compared to assess the anatomical accuracy of the 3D printed models. The neurologic assessment was evaluated by Japanese Orthopedic Association (JOA) score before and after surgery. METHODS The anatomy of the 3D printed model was thoroughly evaluated and the scheme of the operation was designed. The posterior fixation option was chosen according to the anatomical characteristics of C1 lateral mass and the width of C2 pars. The simulation of screw insertion was made to obtain the ideal entry point and screw trajectory. After obtaining the individual data in 3D printing modes, the according surgical operations were performed. RESULTS A total of 24 patients underwent this patient-specific perioperative simulation of procedures and intraoperative orientation guided by 3D printed model between the ages of 15 and 40 years (mean: 25.8 years). There was no intraoperative neurovascular injury in all cases. The operative time ranged from 120 to 220 minutes (mean: 150±18 minutes), and blood loss ranged from 90 to 380 mL (mean: 110±35 mL). Neurological improvement was observed in all 24 patients, with the JOA scores increasing from preoperative 10.1 to postoperative 15.5 (p˂0.01). CONCLUSIONS 3D printing mode could provide thorough information of the bony structure abnormalities and route of vertebral artery. It is helpful for setting operation strategy and designing screw entry point and trajectory and avoiding vertebral artery and spinal cord injury and thus deserves generalization. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.