老年人普遍有骨質疏鬆的症狀，隨著台灣邁入高齡化社會，因骨質疏鬆所造成的壓迫性骨折也有越來越多的趨勢。
現今研究中，較少探討到骨質疏鬆病患因胸腰椎骨折接受手術治療的研究，針對接受不同手術的骨質疏鬆病患，包括常見的後方脊椎內固定融合手術、骨水泥椎體灌注等手術，不同手術會使脊椎有不同的力學表現，為了有效了解骨質疏鬆病患手術後的脊椎生物力學情形，我們利用有限元素分析軟體Patran、ABAQUS，將各種控制變因進行考量，如不同材質骨水泥(PMMA、CPC)、骨水泥分布位置、有無短節鋼釘的影響，來進行生物力學研究探討。
本研究使用CT掃描的方式建立起脊椎模組，在腰椎第一節(L1)的部位，取中間二分之一的位置，將鬆質骨與皮質骨的材料參數弱化為十分之一，來模擬腰椎第一節發生骨折的情形，另外，本研究採用有螺紋的骨釘來建立Pedicle Screw系統，利用Patran有限元素分析前處理軟體在T12與L2椎節處植入骨釘，最後比較在四種動作下(前彎、後仰、側彎、扭轉)下，L1鄰近節和骨釘的應力分布情形，以及脊椎的穩定度與活動度影響。

The elderly generally have symptoms of osteoporosis, compression fractures caused by osteoporosis is a growing trend with Taiwan to become an aging society.
In the present study, less attention to the study of osteoporosis patients received surgical treatment for thoracolumbar fractures for osteoporosis patients receiving surgery, including Vertebroplasty or Posterior Spinal Fixation, various operation would have the spine have different mechanical performance. In order to understand the Biomechanics for Osteoporotic Thoracolumbar Vertebral Fracture after surgery, we use finite element software Patran, ABAQUS to analyze and consider different control variables such as different materials for bone cement(PMMA ,CPC), the location where bone cement inject, the effect of implanting pedicle screws or not. Use these to analyze the effects in Biomechanics.
CT scans used in this study to establish the spine module, in the lumbar part of Section 1 (L1), take the position of the middle half, weakening the material parameters of cancellous bone and cortical bone for the tenth to simulate the case of fracture of the lumbar section I. Also, we established pedicle screw system with screw thread, and we use FEM software Patran to insert pedicle screw into T12 and L2 segments.
Finally, stress in the pedicle screws , stress in the segments near L1 fracture, spinal stabilities and ROM under four motions(Flexion, Extension, Lateral Bending and Rotation) were compared.

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