Biomechanical evaluation of strategies for adjacent segment disease after lateral lumbar interbody fusion: is the extension of pedicle screws necessary?

Bibliographic Details
Title: Biomechanical evaluation of strategies for adjacent segment disease after lateral lumbar interbody fusion: is the extension of pedicle screws necessary?
Authors: Ziyang Liang, Jianchao Cui, Jiarui Zhang, Jiahui He, Jingjing Tang, Hui Ren, Linqiang Ye, De Liang, Xiaobing Jiang
Source: BMC Musculoskeletal Disorders, Vol 21, Iss 1, Pp 1-14 (2020)
Publisher Information: BMC, 2020.
Publication Year: 2020
Collection: LCC:Diseases of the musculoskeletal system
Subject Terms: Diseases of the musculoskeletal system, RC925-935
More Details: Abstract Background Adjacent segment disease (ASD) is a well-known complication after interbody fusion. Pedicle screw-rod revision possesses sufficient strength and rigidity. However, is a surgical segment with rigid fixation necessary for ASD reoperation? This study aimed to investigate the biomechanical effect of different instrumentation on lateral lumbar interbody fusion (LLIF) for ASD treatment. Methods A validated L2~5 finite element (FE) model was modified for simulation. ASD was considered the level cranial to the upper-instrumented segment (L3/4). Bone graft fusion in LLIF with bilateral pedicle screw (BPS) fixation occurred at L4/5. The ASD segment for each group underwent a) LLIF + posterior extension of BPS, b) PLIF + posterior extension of BPS, c) LLIF + lateral screw, and d) stand-alone LLIF. The L3/4 range of motion (ROM), interbody cage stress and strain, screw-bone interface stress, cage-endplate interface stress, and L2/3 nucleus pulposus of intradiscal pressure (NP-IDP) analysis were calculated for comparisons among the four models. Results All reconstructive models displayed decreased motion at L3/4. Under each loading condition, the difference was not significant between models a and b, which provided the maximum ROM reduction (73.8 to 97.7% and 68.3 to 98.4%, respectively). Model c also provided a significant ROM reduction (64.9 to 77.5%). Model d provided a minimal restriction of the ROM (18.3 to 90.1%), which exceeded that of model a by 13.1 times for flexion-extension, 10.3 times for lateral bending and 4.8 times for rotation. Model b generated greater cage stress than other models, particularly for flexion. The maximum displacement of the cage and the peak stress of the cage-endplate interface were found to be the highest in model d under all loading conditions. For the screw-bone interface, the stress was much greater with lateral instrumentation than with posterior instrumentation. Conclusions Stand-alone LLIF is likely to have limited stability, particularly for lateral bending and axial rotation. Posterior extension of BPS can provide reliable stability and excellent protective effects on instrumentation and endplates. However, LLIF with the use of an in situ screw may be an alternative for ASD reoperation.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1471-2474
Relation: http://link.springer.com/article/10.1186/s12891-020-3103-1; https://doaj.org/toc/1471-2474
DOI: 10.1186/s12891-020-3103-1
Access URL: https://doaj.org/article/49ec650cfd0649129e4be0bfe1807c42
Accession Number: edsdoj.49ec650cfd0649129e4be0bfe1807c42
Database: Directory of Open Access Journals
Full text is not displayed to guests.
More Details
ISSN:14712474
DOI:10.1186/s12891-020-3103-1
Published in:BMC Musculoskeletal Disorders
Language:English