在骨科手術中，骨板廣泛地被用來治療各種部位的骨折，而新型的鎖定式骨板(Locking plate)其螺絲與骨板可用螺紋系統結合，因此比傳統的動態加壓骨板(dynamic compression plate)要能提供更佳的穩定度。然而螺紋含量之幾何所造成骨板應力下降之趨勢，進而降低元件之疲勞壽命，而使其使用壽命增加。因此本研究目的為探討不同螺紋合併孔洞設計與偏心孔洞設計對鎖定式骨板機械性能優劣性之影響。

通常機械斷裂有兩種情況：植入物鬆脫和植入物斷裂，當螺絲鬆開到與骨板分離時，此現象為植入物鬆脫，而病人在經長時間的走路或過度使用後導致骨板發生破壞的情形，則稱為植入物斷裂，通常手術技術不正確或植入物設計不當，皆可能會發生機械斷裂。不正確的手術技術包括錯誤選擇板，骨板板太短，螺釘數量不足，骨板的螺絲密度或工作長度不足，螺絲鎖歪，較大的骨折間隙以及過早進行承重活動。植入物設計不良包括材料選擇錯誤，幾何形狀不合適或尺寸過小的鋼板和螺釘。

在本文中，分為生物力學測試以及有限元素分析兩部分，在生物力學測試方面，總共對五種骨板進行降伏測試與疲勞測試，而在實驗後得到位移、負載之關係而計算出其降伏強度與疲勞壽命；而在有限元素分析方面，利用 SolidWorks 建立三維骨板模型並匯入 ANSYS 來進行模擬，其負荷情形與邊界條件和機械測試相同，並得到有限元素分析數值之最大張應力與位移，並將生物力學測試與有限元素分析做一相關性的比較。有限元素分析結果顯示，合併孔洞之螺紋孔洞移除1/3螺紋後之應力下降最多。此生物力學研究結果可以提供給相關工程師做為改良鎖定式骨板之設計参考。

In orthopedic surgery, bone plates are widely used to treat fractures in various parts, and the new type of locking plate (Locking plate), the screw and bone plate can be combined with a thread system, so it is better than the traditional dynamic compression plate (dynamic compression plate). The compression plate) should be able to provide better stability. However, the geometry of the thread content causes the stress of the bone plate to decrease, thereby reducing the fatigue life of the component and increasing its service life. Therefore, the purpose of this study is to investigate the influence of different thread combined hole design and eccentric hole design on the mechanical properties of locking bone plates.

Generally, there are two cases of mechanical fracture: implant loosening and implant fracture. When the screw is loosened and separated from the bone plate, this phenomenon is the implant loosening, and the patient is walking for a long time or overuse The subsequent damage to the bone plate is called implant fracture. Usually, if the surgical technique is incorrect or the implant is not designed properly, mechanical fracture may occur. Incorrect surgical techniques include incorrect selection of plates, too short bone plates, insufficient number of screws, insufficient screw density or working length of the bone plates, crooked screw locks, large fracture gaps, and premature weight bearing activities. Poor implant design includes incorrect material selection, improper geometry or undersized steel plates and screws.

In this article, it is divided into two parts: biomechanical test and finite element analysis. In terms of biomechanical test, a total of five types of bone plates are subjected to yield test and fatigue test. After the experiment, the relationship between displacement and load is obtained and the yield is calculated Strength and fatigue life; and in terms of finite element analysis, using SolidWorks to build a three-dimensional bone plate model and importing it into ANSYS for simulation, the load situation is the same as the boundary conditions and mechanical tests, and the maximum tensile stress and displacement of the finite element analysis value are obtained , And make a correlation comparison between biomechanical testing and finite element analysis. The results of finite element analysis showed that the stress drop of the threaded hole of the combined hole was the most after removing 1/3 of the thread. The results of this biomechanical study can be provided to relevant engineers as a reference for the design of improved locking bone plates.

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