Finite element analysis of the stress distribution of spinal fusion versus non-fusion surgeries / 中国组织工程研究

ABSTRACT

BACKGROUND: At present, traditional interbody fusion is still the main method for lumbar degeneration, and non-fusion treatment has achieved rapid development in recent years, but the effects of two kinds of methods on the lumbar biomechanics deserve a further study. OBJECTIVE: To explore the load distribution on the degenerative lumbar vertebrae, and pathogenesis of lumbar spine degeneration through finite element analysis; and to compare the stress distribution on the lumbar vertebrae and treatment outcomes after fusion and non-fusion surgeries. METHODS: The finite element models of four groups were established, respectively, based on the CT images, including normal lumbar spine, lumbar intervertebral disc herniation, and lumbar spine after fusion and non-fusion surgeries. The four groups were modeled in neutral position, lateral flexion, flexion and rotation by workbench 17.0, and the finite element analysis of stress and statics was conducted. RESULTS AND CONCLUSION: (1) The finite element analysis of degenerative lumbar spine showed that the stress of intervertebral disc mainly concentrated on the posterior part of the annulus fibrosus. The degenerative annulus fibrosus easily became thin under stress, thus affecting the lumbar stability. (2) The comparative analysis results found that the finite element results of the lumbar spine after non-fusion surgery were closer to those of the normal lumbar spine. Therefore, non-fusion surgery can achieve better repair outcomes in the treatment of lumbar vertebral degeneration.