Improving the trajectory of transpedicular transdiscal lumbar screw fixation with a computer-assisted 3D-printed custom drill guide

PeerJ. 2017 Jul 13;5:e3564. doi: 10.7717/peerj.3564. eCollection 2017.

Abstract

Transpedicular transdiscal screw fixation is an alternative technique used in lumbar spine fixation; however, it requires an accurate screw trajectory. The aim of this study is to design a novel 3D-printed custom drill guide and investigate its accuracy to guide the trajectory of transpedicular transdiscal (TPTD) lumbar screw fixation. Dicom images of thirty lumbar functional segment units (FSU, two segments) of L1-L4 were acquired from the PACS system in our hospital (patients who underwent a CT scan for other abdomen diseases and had normal spine anatomy) and imported into reverse design software for three-dimensional reconstructions. Images were used to print the 3D lumbar models and were imported into CAD software to design an optimal TPTD screw trajectory and a matched custom drill guide. After both the 3D printed FSU models and 3D-printed custom drill guide were prepared, the TPTD screws will be guided with a 3D-printed custom drill guide and introduced into the 3D printed FSU models. No significant statistical difference in screw trajectory angles was observed between the digital model and the 3D-printed model (P > 0.05). Our present study found that, with the help of CAD software, it is feasible to design a TPTD screw custom drill guide that could guide the accurate TPTD screw trajectory on 3D-printed lumbar models.

Keywords: Lumbar spine; Three dimensional printed template; Three dimensional reconstruction; Transpedicular transdiscal lumbar screw fixation.

Grant support

This work was supported by the National Natural Science Foundation of China (81501933, 81572214), Wenzhou Science and Technology Project (Y20160369), Scientific research project for student of Wenzhou Medical University (WYX201401020), Natural Science Foundation of China Zhejiang Province (LY14H060008). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.