Lumbar biomechanical characteristics after microsurgical lumbar discectomy with different proportions of nucleus pulposus:finite element analysis
Chen Hua-xing
Yang Sheng
Lu Jian-min
Yu Yan-nan
Yuan Chi
Ren Fu-quan
Liu Ji-feng
Zhao Guo-quan
Li Shu-qiang
Abstract：BACKGROUND:Most finite element models of microsurgical lumbar discectomy are built on the basis of normal vertebral bodies in China to remove the complete nucleus pulposus tissue. However, it did not consider the only part of nucleus pulposus removal in the process of actual operation and the impact of vertebral lamina fenestration on spinal mechanics at the same time. <br> OBJECTIVE:To establish precisely three-dimensional finite element model (L4/5) to compare biomechanical characteristics caused by the different proportions of discectomy under a microscope. <br> METHODS:One patient with lumbar intervertebral disc herniation was selected. Preoperative CT data were used to construct finite element models, and its effectiveness was validated. Postoperative CT data were col ected. Degeneration model, vertebral lamina fenestration model, microsurgical lumbar discectomy model (removal of a third of nucleus pulposus) and al nucleus pulposus resection model were constructed. Under specific loading conditions, biomechanical characteristics were compared in the flexion-extension, lateral bending, and axial rotation conditions. <br> RESULTS AND CONCLUSION:Finite element models of lumbar vertebrae were accurately established after discectomy at various proportions under the microscope. Mechanical property analysis demonstrated that after microsurgical lumbar discectomy and removing different proportions of nucleus pulposus, under flexion-extension condition, the end max-stress distributed in the isthmus and the superior articular facet, besides the stability of the lumbar spine, was reduced. This change on the opposite direction of vertebral lamina fenestration was most <br> obvious when lateral-bending and backward extension condition. The proportion of nucleus pulposus removal was associated with its effects.
Keywords：lumbar vertebraeintervertebral disk displacementmicroscopybiomechanicsfinite element analysis
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 2659-2666 )