Optimization of Spondylosynthesis for Certain Thoracolumbar Burst Fractures

S V Likhachev; V B Arsenievich; V V Ostrovskiy; A E Shulga; A V Zaretskov; D V Ivanov; A V Dol; A M Donnik; V V Zaretskov

doi:10.17691/stm2020.12.4.04

Optimization of Spondylosynthesis for Certain Thoracolumbar Burst Fractures

Sovrem Tekhnologii Med. 2021;12(4):30-38. doi: 10.17691/stm2020.12.4.04. Epub 2020 Aug 27.

Authors

S V Likhachev¹, V B Arsenievich², V V Ostrovskiy³, A E Shulga¹, A V Zaretskov⁴, D V Ivanov⁵, A V Dol⁵, A M Donnik⁶, V V Zaretskov⁷

Affiliations

¹ Senior Researcher, Department of Innovative Projects in Neurosurgery and Vertebrology, Research Institute of Traumatology, Orthopedics, and Neurosurgery; V.I. Razumovsky Saratov State Medical University, 112 Bolshaya Kazachya St., Saratov, 410012, Russia.
² Head of Traumatology and Orthopedics Department No.3, Research Institute of Traumatology, Orthopedics, and Neurosurgery; V.I. Razumovsky Saratov State Medical University, 112 Bolshaya Kazachya St., Saratov, 410012, Russia.
³ Director, Research Institute of Traumatology, Orthopedics, and Neurosurgery; V.I. Razumovsky Saratov State Medical University, 112 Bolshaya Kazachya St., Saratov, 410012, Russia.
⁴ Associate Professor, Department of Traumatology and Orthopedics; V.I. Razumovsky Saratov State Medical University, 112 Bolshaya Kazachya St., Saratov, 410012, Russia.
⁵ Associate Professor, Department of Mathematical Theory of Elasticity and Biomechanics; Saratov State University, 83 Astrakhanskaya St., Saratov, 410012, Russia.
⁶ Assistant, Department of Mathematical Theory of Elasticity and Biomechanics; Saratov State University, 83 Astrakhanskaya St., Saratov, 410012, Russia.
⁷ Leading Researcher, Department of Innovative Projects in Neurosurgery and Vertebrology, Research Institute of Traumatology, Orthopedics, and Neurosurgery; V.I. Razumovsky Saratov State Medical University, 112 Bolshaya Kazachya St., Saratov, 410012, Russia; Professor, Department of Traumatology and Orthopedics V.I. Razumovsky Saratov State Medical University, 112 Bolshaya Kazachya St., Saratov, 410012, Russia.

Abstract

Intermediate transpedicular fixation, i.e. additional insertion of transpedicular screws into the injured vertebrae, is an improvement to the most popular surgical intervention for spinal injuries, currently gaining widespread use in clinical practice. Unilateral insertion of transpedicular screws into the injured vertebrae allows combining the advantages of intermediate transpedicular fixation with the possibility to perform anterior column support without remounting the transpedicular system. The aim of the study was to use biomechanical computer modeling for evaluating the stability of intermediate transpedicular fixation components, which allow performing anterior column support if necessary.

Materials and methods: DICOM files obtained during CT scan of a patient with intermediate thoracolumbar spine injury and the ANSYS software were used. Stability of the transpedicular system and supportability of the complementary Mesh implant installed with unilateral intermediate transpedicular screws were evaluated using computer modeling based on the finite element method.

Results: The values of stress and displacement fields for spine-hardware systems with various arrangements have been obtained. The maximum loads exceeding bone tissue strength (153-161 MPa) were registered for standard 4-screw system (190 MPa) when modeling the load equivalent for walking and falling from a standing position. The use of the proposed fixation system arrangement supplemented with intermediate screws allows obtaining loads in the spine-hardware system not exceeding these thresholds. Complementary eccentric Mesh implant enhances fixation stability of the transpedicular system with intermediate screws.

Conclusion: The results show the high degree of mechanical stability of the proposed hardware arrangement and its potential efficacy for thoracolumbar transitional vertebra stabilization.

Keywords: anterior column support.; finite element method; intermediate transpedicular fixation; spine trauma; thoracolumbar transitional vertebra.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Fracture Fixation, Internal / methods
Humans
Lumbar Vertebrae / diagnostic imaging
Spinal Fractures* / diagnostic imaging
Thoracic Vertebrae* / diagnostic imaging
Treatment Outcome

Grants and funding

Study funding. The study was performed within the frame of State Assignment No.154018-03 “Development of surgical reconstruction technology for unstable injuries of the thoracolumbar spine based on biomechanical modeling”.