Application of navigation template to fixation of sacral fracture using three-dimensional reconstruction and re-verse engineering technique

摘要

Objective: To provide a new method in the fixation of sacral fracture by means of three-dimensional reconstruc-tion and reverse engineering technique.Methods: Pelvis image data were obtained from three-dimensional CT scan in patients with sacral fracture. The data were transferred into a computer workstation. The three-dimensional models of pelvis were reconstructed using Amira 3.1 software and saved in STL format. Then the three-dimensional fracture models were imported into Imageware 9.0 software. Different situations of reduction (total reduction, half reduction and non-reduction) were simulated using Imageware 9.0 software. The best direction and loca-tion of extract iliosacral lag screws were defined using re-verse engineering according to these three situations and navigation templates were designed according to the ana-tomic features of the postero-iliac part and the channel. The exact navigational template was made by rapid prototyping.Drill guides were sterilized and used intraoperatively to as-sist in surgical navigation and the placement of iliosacral lag screws.Results: Accurate screw placement was confirmed with postoperative X-ray and CT scanning. The navigation template was found to be highly accurate. Conclusion: The navigation template may be a useful method in minimal-invasive fixation of sacroiliac joint fracture.