Department of Mechanical Engineering, National Institute of Technology, Patna, India.
Department of Aerospace Engineering and Applied Mechanics, Indian Institute of Engineering Science and Technology, Shibpur, India.
Int J Artif Organs. 2022 Feb;45(2):193-199. doi: 10.1177/03913988211001875. Epub 2021 Mar 11.
Degenerative disc disease (DDD) in lumbar spine is one of the major musculoskeletal disorders that cause low back pain (LBP). The intervertebral disc structure and dynamics of the lumbar spine are significantly affected by lumbar DDD, leading to a reduced range of motion (ROM), muscle weakness and gradual degradation. Spinal fusion and inter-vertebral disc replacement prostheses are two major surgical methods used for treating lumbar DDD. The aim of this present study is to examine biomechanical impacts of single level (L3-L4 and L4-L5) and multi level (L3-L4-L5) inter-vertebral disc replacement in lumbar spine (L2-L5) and to compare the performance with intact spine. Finite element (FE) analysis has been used to compare the mobility and stress distribution of all the models for four physiological movements, namely flexion, extension, left and right lateral bending under 6, 8 and 10 Nm moments. Spinal fusion implants completely restrict the motion of the implanted segment and increase disc stress at the adjacent levels. In contrast to that, the results single level ADR models showed closer ROM and disc stress to natural model. At the spinal segments adjacent to the implantation, single level ADR shows lower chance of disc degeneration. However, significantly increased ROM was observed in case of double level ADR.
腰椎退行性椎间盘疾病（DDD）是导致下腰痛（LBP）的主要骨骼肌肉疾病之一。腰椎 DDD 显著影响腰椎间盘的结构和动力学，导致运动范围（ROM）减小、肌肉无力和逐渐退化。脊柱融合和椎间盘置换假体是治疗腰椎 DDD 的两种主要手术方法。本研究旨在研究单节段（L3-L4 和 L4-L5）和多节段（L3-L4-L5）腰椎（L2-L5）椎间盘置换对生物力学的影响，并将其性能与完整脊柱进行比较。有限元（FE）分析用于比较所有模型在四个生理运动（前屈、伸展、左右侧屈）下在 6、8 和 10 Nm 力矩下的活动性和应力分布。脊柱融合植入物完全限制了植入节段的运动，并增加了相邻节段的椎间盘应力。相比之下，单节段 ADR 模型的结果显示出与自然模型更接近的 ROM 和椎间盘应力。在植入部位相邻的脊柱节段，单节段 ADR 显示出较低的椎间盘退化几率。然而，在双节段 ADR 的情况下，观察到 ROM 显著增加。
