A novel entry point for pedicle screw placement in the thoracic spine

Abstract

This study was aimed to introduce a novel entry point for pedicle screw fixation in the thoracic spine and compare it with the traditional entry point. A novel entry point was found with the aim of improving accuracy, safety and stability of pedicle screw technique based on anatomical structures of the spine. A total of 76 pieces of normal thoracic CT images at the transverse plane and the thoracic pedicle anatomy of 6 cadaveric specimens were recruited. Transverse pedicle angle (TPA), screw length, screw placement accuracy rate and axial pullout strength of the two different entry point groups were compared. There were significant differences in the TPA, screw length, and the screw placement accuracy rate between the two groups (P<0.05). The maximum axial pullout strength of the novel entry point group was slightly larger than that of the traditional group. However, the difference was not significant (P>0.05). The novel entry point significantly improved the accuracy, stability and safety of pedicle screw placement. With reference to the advantages above, the new entry point can be used for spinal internal fixations in the thoracic spine.

Keywords

entry point / screw placement / thoracic spine / biomechanical stability

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Acknowledgments

This work was supported by the National Natural Science Foundation of China (Grant #81371968, #81371969,#81401791); the Program for Development of Innovative Research Team in the First Affiliated Hospital of NJMU (No. IRT-015), and a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.

RIGHTS & PERMISSIONS

2017 2017 by the Journal of Biomedical Research.