腰椎後路穩定系統設計最佳化及其生物力學影響

陶仕晉(Shi-jin Tao)

指導教授 ： 黃俊仁

國立中央大學/工學院/機械工程學系/碩士(2014年)

摘要

人體脊椎會因為老化或意外產生病變。本文主要是探討當人體脊椎有椎間盤退化情形，進行腰椎非骨融合手術後，探討腰椎的初期生物力學行為。同時考量微創手術便利性新設計一種後路穩定系統。
本研究使用AMIRA 與SolidWorks 建立L3-L5 腰椎模型，將L4/5椎間盤更改為椎間盤退化之參數，並分別植入剛性穩定系統、DYNESYS系統，再以ANSYS Workbench進行有限元素分析，探討其初期之生物力學行為。此外將新設計系統植入退化模型後進行田口品質分析。探討的品質特性有L3/4椎間盤運動範圍(ROM)、L3/4椎間盤應力與L4/5椎間盤。最後找出新設計系統的最佳化設計，並與其他系統進行比較。
結果顯示在前彎、後仰、側彎與扭轉等四個運動模式，新設計系統在品質特性L3/4椎間盤ROM以多品質最佳化效果最佳。但在品質特性L4/5椎間盤應力以單一品質最佳化效果最佳。各運動模式下產生之最佳化系統以扭轉模式為最佳設計(T-BEST)。退化模型在退化節(L4/5)因髓核脫水與纖維環變硬後，在各運動模式此節的運動範圍(ROM)均減少，且應力均有提升的情形。當植入剛性桿除了前彎其餘運動模式在植入節 (L4/5)應力均會降低，產生應力遮蔽情形。植入DYNESYS系統則在前、後彎時植入節 (L4/5)應力明顯提升；在鄰近節(L3/4)植入剛性桿後ROM有提升，相反的在植入DYNESYS系統後則ROM提升情況產生的並不明顯。植入T-BEST系統，在植入節(L4/5)椎間盤於大多數的運動模式均能恢復與健康模型相近的應力。與健康模型相比，植入T-BEST系統在鄰近節(L3/4)比植入DYNESYS系統有較佳的ROM值。T-BEST滿足了一定的穩定度且有比剛性模型較高的活動量。

關鍵字

非骨融合手術 ； 後路穩定系統 ； 有限元素法 ； 田口品質法 ； 主成份分析

並列摘要

The human spine causes lesions because of aging or accidents. This article focuses on the human spine has degenerative disc. After non-fusion surgery, the initial biomechanical behaviors were discussed. We not only designed a posterior stabilization system but also considered the convenience of minimally invasive surgery at the same time.
The software AMIRA and SolidWorks were adopted to establish the L3-L5 lumbarmodel. The property of L4/L5 intervertebral disc was changed by degeneration parameter. The model was implanted by rigid stabilization system and DYNESYS stabilization system, respectively in difference. The initial biomechanical behavior was explored by using ANSYS Workbench to perform finite element analysis. In addition, the Taguchi methods analysis was performed after the degradation model was implanted by the new design system. There were characteristics of discussing qualities that were range of motion of L3/4 disc, stress of L3/4 disc, and stress of L4/5 disc. Finally, the optimal design of the new design system was founded and compared with other systems.
The results showed that the quality characteristics of new design system of multi-quality optimized is the best on ROM of L3/4 disc in the case of flexion, extension, lateral Bending, and rotation. However, the quality characteristics of new design system that single-quality optimization is the best on stress of L4/5 disc in the each motion mode. Each motion mode produced the optimize systems. The rotation mode was the best in each motion mode (T-BEST). The ROM of degradation model was reduced on the degradation disc (L4/5) in each motion mode, and the stress of degradation disc was increased because dehydration of nucleus pulposus and hardening of annulus. When the degradation model was implanted by rigid rod, the stress of implanted festivaldisc (L4/5) was reduced except flexion. It was stress shielding case. When the degradation model was implanted by DYNESYS, the stress of implanted festival disc (L4/5) was increased significantly in flexion and extension. When the degradation model was implanted by rigid rod, the ROM of adjacent disc (L3/4) was increased, and when the degradation model was implanted by DYNESYS, the stress was not increased in flexion and extension. The model was similar to health model which was implanted T-BEST system on the stress of implanted festival disc (L4/5). The model which was implanted T-BEST system is better value than the model that was implanted DYNESYS system compared with healthy model on the ROM of adjacent disc. T-BEST met a certain amount of stability and a higher activity than the amount of rigid rod.

並列關鍵字

Non-Fusion Surgery ； Posterior Stabilization System ； Finite Element Methods ； Taguchi Methods ； Principal Component Analysis

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