P7. Effect of cage position and insertion angle in the oblique lumbar interbody fusion: A finite element study

Objective: To investigate the biomechanical effects of osteoporosis on adjacent segments after posterior lumbar interbody fusion (PLIF). Methods: This study was designed and conducted in the Traumatology and Orthopedics Laboratory, School of Chinese Medicine, Jinan University, Guangzhou, China, between December 2019 and February 2020. A healthy finite element model of L3-S1 was developed along with one PLIF model and one PLIF with osteoporosis model. Based on a hybrid test method, the inferior surface of S1 was entirely fixed, and a preload of 400N combined with an adjusted moment was imposed on the superior surface of L3 in each model to simulate flexion, extension, lateral bending and axial rotation. The intradiscal pressure (IDP), shear stress on annulus fibrosus, and the range of motion (ROM) of L3-L4 and L5-S1 were calculated and compared. Results: In each direction, the highest value of IDP and shear stress on annulus fibrosus at L3-L4 and L5-S1 was found in the PLIF model, and the lowest value in the healthy model. The largest ROM at L4-L5 appeared in the healthy model, and the smallest value in the PLIF model in each direction. At L3-L4 and L5-S1, the highest ROM in most directions was found in the PLIF model, followed by the PLIF with osteoporosis model, and the lowest value in the healthy model. Conclusions: Osteoporosis can decrease IDP, shear stress on annulus fibrosus, and ROM at adjacent levels, and slow down the development of ASD after PLIF. doi: https://doi.org/10.12669/pjms.37.2.3223 How to cite this:Zhang C, Chang M, Zhang R, Tang S. Biomechanical effects of osteoporosis on adjacent segments after posterior lumbar interbody fusion: A finite element study. Pak J Med Sci. 2021;37(2):---------. doi: https://doi.org/10.12669/pjms.37.2.3223 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Bilateral pedicle screw fixation provides superior biomechanical stability in transforaminal lumbar interbody fusion: a finite element study

The Spine Journal ◽

10.1016/j.spinee.2014.06.015 ◽

2015 ◽

Vol 15 (8) ◽

pp. 1812-1822 ◽

Cited By ~ 45

Author(s):

Divya V. Ambati ◽

Edward K. Wright ◽

Ronald A. Lehman ◽

Daniel G. Kang ◽

Scott C. Wagner ◽

...

Keyword(s):

Finite Element ◽

Pedicle Screw ◽

Interbody Fusion ◽

Screw Fixation ◽

Transforaminal Lumbar Interbody Fusion ◽

Pedicle Screw Fixation ◽

Lumbar Interbody Fusion ◽

Biomechanical Stability ◽

Bilateral Pedicle Screw ◽

Element Study

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Biomechanical evaluation of an oblique lateral locking plate system for oblique lumbar interbody fusion: a finite element analysis

World Neurosurgery ◽

10.1016/j.wneu.2021.12.105 ◽

2022 ◽

Author(s):

Yinge Wang ◽

Jiajia Wang ◽

Sha Tu ◽

Shuang Li ◽

Jiangpu Yi ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Interbody Fusion ◽

Locking Plate ◽

Lumbar Interbody Fusion ◽

Element Analysis ◽

Biomechanical Evaluation ◽

Oblique Lumbar Interbody Fusion ◽

Locking Plate System ◽

Plate System

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Biomechanical Evaluation of Anterolateral Screw Fixation for Oblique Lumbar Interbody Fusion Surgery – A Finite Element Analysis

10.21203/rs.3.rs-71475/v1 ◽

2020 ◽

Author(s):

gufang Fang ◽

SG Chen ◽

wda zhuang ◽

WH Huang ◽

Hongxun Sang

Keyword(s):

Finite Element ◽

Interbody Fusion ◽

Screw Fixation ◽

Upper Body ◽

Lumbar Interbody Fusion ◽

Element Analysis ◽

Flexion Extension ◽

Cage Subsidence ◽

Oblique Lumbar Interbody Fusion ◽

Maximum Stresses

Abstract Background: The most common complication of oblique lumbar interbody fusion (OLIF) is cage subsidence. OLIF combined with internal fixation could help decrease the cage subsidence and increase the fusion rate. The aim of this study was to evaluate the biomechanical feasibility and safety in the patients undergoing OLIF surgery with anterolateral screw fixation (ASF). Methods: Based on our previous validated model , L4-L5 functional surgical models corresponding to the ASF and Bilateral pedicle screw fixation(BPSF) methods were created. A 500 N compression force was applied to the superior surface of the model to represent the upper body weight, and a 7.5 Nm moment was applied to simulate the six movement directions of the lumbar spinal model: flexion/extension, right/left lateral bending and right/left axial rotation. Finite element (FE) models were developed to compare the biomechanics of the ASF and BPSF groups. Results: Compared to the range of motion (ROM) of the intact lumbar model, that of the ASF model was decreased by 82.0% in flexion, 60.0% in extension, and the BPSF model was decreased by 86.7% in flexion, 77.3% in extension. Compared to the BPSF model, the maximum stresses of the L4 inferior endplate (IEP) and L5 superior endplate (SEP) were greatly increased in the ASF model; The contact surface between vertebrae and screw (CSVS) in the ASF model produced nearly100% more stresses than the BPSF model in all moment .Conclusions: OLIF surgery with ASF could not reduce the maximum stresses on the endplate and CSVS, which may be a potential risk factor for cage subsidence and screw loosening.

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