Cargando…

Biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis

BACKGROUND: The influence of total en bloc spondylectomy (TES) on spinal stability is substantial, necessitating strong fixation to restore spinal stability. The transverse connector (TC) serves as a posterior spinal instrumentation that connects the left and right sides of the pedicle screw-rod sys...

Descripción completa

Detalles Bibliográficos
Autores principales: Han, Ye, Ren, Xuehong, Liang, Yijie, Ma, Xiaoyong, Wang, Xiaodong
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10324273/
https://www.ncbi.nlm.nih.gov/pubmed/37408002
http://dx.doi.org/10.1186/s13018-023-03977-1
_version_ 1785069117072474112
author Han, Ye
Ren, Xuehong
Liang, Yijie
Ma, Xiaoyong
Wang, Xiaodong
author_facet Han, Ye
Ren, Xuehong
Liang, Yijie
Ma, Xiaoyong
Wang, Xiaodong
author_sort Han, Ye
collection PubMed
description BACKGROUND: The influence of total en bloc spondylectomy (TES) on spinal stability is substantial, necessitating strong fixation to restore spinal stability. The transverse connector (TC) serves as a posterior spinal instrumentation that connects the left and right sides of the pedicle screw-rod system. Several studies have highlighted the potential of a TC in enhancing the stability of the fixed segments. However, contradictory results have suggested that a TC not only fails to improve the stability of the fixed segments but also might promote stress associated with internal fixation. To date, there is a lack of previous research investigating the biomechanical effects of a TC on TES. This study aimed to investigate the biomechanical effects of a TC on internal fixation during TES of the lumbar (L) spine. METHODS: A single-segment (L3 segment) TES was simulated using a comprehensive L spine finite element model. Five models were constructed based on the various positions of the TC, namely the intact model (L1-sacrum), the TES model without a TC, the TES model with a TC at L1–2, the TES model with a TC at L2–4, and the TES model with a TC at L4–5. Mechanical analysis of these distinct models was conducted using the Abaqus software to assess the variations in the biomechanics of the pedicle screw-rod system, titanium cage, and adjacent endplates. RESULTS: The stability of the surgical segments was found to be satisfactory across all models. Compared with the complete model, the internal fixation device exhibited the greatest constraint on overextension (95.2–95.6%), while showing the least limitation on left/right rotation (53.62–55.64%). The application of the TC had minimal effect on the stability of the fixed segments, resulting in a maximum reduction in segment mobility of 0.11° and a variation range of 3.29%. Regardless of the use of a TC, no significant changes in stress were observed for the titanium cage. In the model without the TC, the maximum von Mises stress (VMS) for the pedicle screw-rod system reached 136.9 MPa during anterior flexion. Upon the addition of a TC, the maximum VMS of the pedicle screw-rod system increased to varying degrees. The highest recorded VMS was 459.3 MPa, indicating a stress increase of 335.5%. Following the TC implantation, the stress on the adjacent endplate exhibited a partial reduction, with the maximum stress reduced by 27.6%. CONCLUSION: The use of a TC in TES does not improve the stability of the fixed segments and instead might result in increased stress concentration within the internal fixation devices. Based on these findings, the routine utilisation of TC in TES is deemed unnecessary.
format Online
Article
Text
id pubmed-10324273
institution National Center for Biotechnology Information
language English
publishDate 2023
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-103242732023-07-07 Biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis Han, Ye Ren, Xuehong Liang, Yijie Ma, Xiaoyong Wang, Xiaodong J Orthop Surg Res Research Article BACKGROUND: The influence of total en bloc spondylectomy (TES) on spinal stability is substantial, necessitating strong fixation to restore spinal stability. The transverse connector (TC) serves as a posterior spinal instrumentation that connects the left and right sides of the pedicle screw-rod system. Several studies have highlighted the potential of a TC in enhancing the stability of the fixed segments. However, contradictory results have suggested that a TC not only fails to improve the stability of the fixed segments but also might promote stress associated with internal fixation. To date, there is a lack of previous research investigating the biomechanical effects of a TC on TES. This study aimed to investigate the biomechanical effects of a TC on internal fixation during TES of the lumbar (L) spine. METHODS: A single-segment (L3 segment) TES was simulated using a comprehensive L spine finite element model. Five models were constructed based on the various positions of the TC, namely the intact model (L1-sacrum), the TES model without a TC, the TES model with a TC at L1–2, the TES model with a TC at L2–4, and the TES model with a TC at L4–5. Mechanical analysis of these distinct models was conducted using the Abaqus software to assess the variations in the biomechanics of the pedicle screw-rod system, titanium cage, and adjacent endplates. RESULTS: The stability of the surgical segments was found to be satisfactory across all models. Compared with the complete model, the internal fixation device exhibited the greatest constraint on overextension (95.2–95.6%), while showing the least limitation on left/right rotation (53.62–55.64%). The application of the TC had minimal effect on the stability of the fixed segments, resulting in a maximum reduction in segment mobility of 0.11° and a variation range of 3.29%. Regardless of the use of a TC, no significant changes in stress were observed for the titanium cage. In the model without the TC, the maximum von Mises stress (VMS) for the pedicle screw-rod system reached 136.9 MPa during anterior flexion. Upon the addition of a TC, the maximum VMS of the pedicle screw-rod system increased to varying degrees. The highest recorded VMS was 459.3 MPa, indicating a stress increase of 335.5%. Following the TC implantation, the stress on the adjacent endplate exhibited a partial reduction, with the maximum stress reduced by 27.6%. CONCLUSION: The use of a TC in TES does not improve the stability of the fixed segments and instead might result in increased stress concentration within the internal fixation devices. Based on these findings, the routine utilisation of TC in TES is deemed unnecessary. BioMed Central 2023-07-05 /pmc/articles/PMC10324273/ /pubmed/37408002 http://dx.doi.org/10.1186/s13018-023-03977-1 Text en © The Author(s) 2023 https://creativecommons.org/licenses/by/4.0/Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) . The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/ (https://creativecommons.org/publicdomain/zero/1.0/) ) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
spellingShingle Research Article
Han, Ye
Ren, Xuehong
Liang, Yijie
Ma, Xiaoyong
Wang, Xiaodong
Biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis
title Biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis
title_full Biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis
title_fullStr Biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis
title_full_unstemmed Biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis
title_short Biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis
title_sort biomechanical effects of transverse connectors on total en bloc spondylectomy of the lumbar spine: a finite element analysis
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10324273/
https://www.ncbi.nlm.nih.gov/pubmed/37408002
http://dx.doi.org/10.1186/s13018-023-03977-1
work_keys_str_mv AT hanye biomechanicaleffectsoftransverseconnectorsontotalenblocspondylectomyofthelumbarspineafiniteelementanalysis
AT renxuehong biomechanicaleffectsoftransverseconnectorsontotalenblocspondylectomyofthelumbarspineafiniteelementanalysis
AT liangyijie biomechanicaleffectsoftransverseconnectorsontotalenblocspondylectomyofthelumbarspineafiniteelementanalysis
AT maxiaoyong biomechanicaleffectsoftransverseconnectorsontotalenblocspondylectomyofthelumbarspineafiniteelementanalysis
AT wangxiaodong biomechanicaleffectsoftransverseconnectorsontotalenblocspondylectomyofthelumbarspineafiniteelementanalysis