To evaluate the individualized 3D printed drilling guide we developed and used for placement of C1/2 pedicle screws in the clinical treatment of fracture and dislocation of the at-lantoaxial joint.

From January 2014 to June 2016, we treated a total of 17 patients with fracture and dislocation of the atlantoaxial joint. All the cervical CT data of the patients were imported into the digital orthopaedic workstation for 3D reconstruction, data modeling and 3D printing to design and manufacture individualized atlantoaxial vertebral guide templates. Intraoperatively, C1 and C2 pedicle screws were placed under the guide of individualized 3D printed drilling template. Cervical short-segment fixation and fusion were conducted for the patients. Postoperatively, regular clinical and radiographic follow-ups were carried out.

No serious complications like injury to spinal cord and vertebral artery happened due to failed placement of C1/2 pedicle screws. The operation time ranged from 136 to 222 min (average, 168.0 min); the intraoperative blood loss ranged from 260 to 556 mL (average, 356.0 mL). The 17 patients were followed up for 6 to 36 months (average, 13.5 months) . The patients obtained bony union after 4 to 6 months (average, 4.8 months). At the final follow-up, according to ASIA92 scoring system, the average sensory score was improved significantly from preoperative 7.4+3.2 to postoperative 13.1+5.9, and the average motor score was improved significantly from preoperative 5.3+3.1 to postoperative 11.7+5.1 (P< 0.05). No such complications as infection or implant failure occurred after operation.

Individualized 3D printed drilling guide for implantation of atlantoaxial pedicle screws can make the complicate and risky placement become accurate, safe and simple.

Cervical vertebrae; Surgery, computer-assisted; Bone nails; 3D printing