腰椎的椎體壓迫性骨折會使脊椎造成椎體變形、不穩定以及疼痛的現象。骨水泥擴張椎體成形術在過去已經被應用於脊椎的椎體壓迫性骨折的治療，減少臨床併發症的風險。骨水泥具有不同的機械強度，在過去已經有發展以及廣泛應用在這個治療上。然而，不同骨水泥治療椎體壓迫性骨折之生物力學結果，在過去還沒有被評估討論。因此，本研究的目的是藉由多節的脊椎有限元素模型，分析出不同類型骨水泥擴張椎體成型術的生物力學特性。
本研究將胸椎第十節至薦椎第一節的三維有限元素模型使用Solidworks建立，包括有椎體(硬質骨、鬆質骨)、後方元件、椎間盤(纖維環、髓核)。模型建立完成後，再匯入Solidworks simulation模式內，針對六種類型的多節脊椎有限元素模型進行分析，其中包括有無骨折模型、骨折裂縫模型、骨折術後強度較高的骨水泥治療模型、骨折術後強度度較低的骨水泥治療模型、骨癒合後強度較高的骨水泥治療模型、骨癒合後強度較低的骨水泥治療模型。評估骨水泥擴張椎體成型術的生物力學特性，是以關節活動度與總應變能分析出的結果呈現。
在不同負載情況下，分析結果顯示在骨癒合後，該肢段的關節活動度(ROM)不會受骨水泥強度的影響。在骨折術後，使用強度高的骨水泥擴張椎體成型術能提供比強度低的骨水泥較高的固定穩定度。此外，強度低的骨水泥擴張椎體成型術在骨癒合後，其生物力學特性幾乎與無骨折模型相同。
希望藉由本研究所得的結果，可幫助外科醫師了解不同類型的骨水泥擴張椎體成型術的生物力學性能，並提供一些選擇資訊給外科醫生。

Vertebral compression fractures of lumbar spine can cause deformity, pain, and disability. Percutaneous vertebral augmentation techniques have been used for vertebral compression fracture treatment to reduce the risks of the clinical complications. Bone cements with varied mechanical strength have been developed and applied to this treatment. However, the effects of mechanical strength of bone cements on the treatment of vertebral compression fractures have not been evaluated and discussed. Therefore, the purpose of this study was to analyze the biomechanical characteristics of percutaneous vertebral augmentation techniques with different types of bone cements by using a multi-level spinal finite element model.
Three-dimensional finite element models of T10-S1 multi-level spinal segments, which consisted of vertebral bodies (cortical bone, and cancellous bone), posterior elements, intervertebral discs (annulus fibrosus and nucleus pulposus), and ligaments, were developed and analyzed by using SolidWorks Simulation in this study. Six types of the multi-level spinal finite element models were evaluated including intact model, fractured model, fractured model with high-strength bone cement after operation, fractured model with low-strength bone cement after operation, fractured model with high-strength bone cement after healing, and fractured model with low-strength bone cement after healing. The range of motion and the total strain energy were calculated to evaluate the biomechanical characteristic of percutaneous vertebral augmentation techniques.
Under different loading conditions, the results showed that the range of motion of the segments was not affected by the strength of bone cements but the bone healing condition. Percutaneous vertebral augmentation with high-strength bone cement after surgical operation could provide more fixation stability than that with low-strength bone cement. In addition, percutaneous vertebral augmentation with low-strength bone cement after fracture healing revealed similar biomechanical characteristics compared with the intact condition. In conclusion, the results of this study could help surgeons to understand the biomechanical performances of percutaneous vertebral augmentation with different types of bone cements and also provide the selection information to surgeons.

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