Development of Lumbar Surgery from Biomechanical Perspectives / 医用生物力学

Lumbar surgical operation is the crucial treatment against lumbar degenerative diseases (LDDs), whose development depends on persistent comprehension and innovation of vertebral biomechanics. The thorough understanding of biomechanical changes during lumbar senescence and degeneration is the important bedrock to grasp LDDs pathogenesis, renovate LDDs surgical strategy, and embrace more precise and minimally invasive treatment against LDDs. Herein, in this review, the intimate crosstalk between LDDs with degenerative biomechanics of vertebrae, intervertebral disc and paravertebral muscles was elucidated, followed by the classification of lumbar surgery history into non-vertebral implant era (before the year 1980), vertebral implant era (during the year 1980-1990), vertebral fusion era (during the year 1990-2010), precise and minimally invasive decompression era (after the year 2010) based on lumbar surgical characteristics in each era. The significance of representative biomechanical studies in each era for lumbar surgery was also concluded. From biomechanical perspectives, the history of spinal surgery is the development history of surgical strategies that has progressed as the continuously in-depth understanding of spinal biomechanics. With the deepening of spinal biomechanical researches, spinal surgeons are expected to develop treatment strategies that are more adapted to physiological and biomechanical characteristics of the spine, thereby guiding the future direction of spinal surgery advancement.

Review on the Progress in Development of Finite Element Models for Functional Spinal Units: Focus on Lumbar and Lumbosacral Levels

@#Functional spinal unit (FSU) has been of major interest in research related to the human spine as it is the simplest entity of spine that is believed to provide vital information useful in analyzing the biomechanics of the spine. In-vitro experiments and in-vivo tests are implemented for this purpose, but due to many restraints in using them, the use of an alternate approach such as Finite Element Analysis (FEA) seems preferential. FEA offers an edge in evaluating significant parameters that may or may not be possible through experiments. The finite element analysis of FSU’s has evolved to handle complexity with the increase in computing capacity and advancement in the software packages. This paper reviews the progress in the development of finite element analysis of FSU’s and also focuses on the application of FEA to analyse the lumbar (L1-L5) and lumbosacral (L5-S1) levels of the spine where spinal disorders are more prevalent.