近年來，骨釘骨板系統的使用已經成為治療骨折的主要方法，隨著多元化的骨折種類和多變的骨頭構造，傳統的骨釘骨板系統並無法完全滿足使用上的需求，因此，新一代骨釘骨板系統陸續被研發出來，但這些設計尚有著鎖付方向不可調整、骨釘骨板冷焊與鎖付力量過高等缺點待改善。
　　本論文藉著3D列印可一體成形製作成品之特色，設計出了可調整鎖付方向並將之固定的骨板系統，此設計解決了無法調整鎖付方向、調整之方向無法固定、無法避免人為鎖入造成之冷焊等問題，也保留了骨釘骨板間以螺紋固定的設計以及增加了降低鎖付力不均勻的設計，並採用珍珠狀骨板增加抗彎曲強度，接著進行模擬與實驗評估此設計襯墊與骨板介面之各項性質。模擬部分為鎖入模擬、拔出模擬及剪切模擬，評估不同干涉量時的固定能力並選出欲測試的干涉量為20 μm。接著針對20 μm的骨板進行鎖入測試、拔出測試及剪力測試。本設計之鎖入扭力約為2.5 N·m，此扭力小於一般骨釘鎖入之操作扭力；抗拔出力數值約為2.5 kN，大於文獻中骨釘與骨頭介面之抗拔出力；抵抗角度改變之臨界力矩約為1 N·m。本論文針對骨釘與骨板接觸介面建立出一套評估方法，此方法將可被應用在更多不同的設計上。

In this research a locking bone plate system with inserted angle fixators for adjusting bone screw angle is developed. Advantages of the design includes locking between the bone plate and screw, adjustable angle up to ±20° for bone screw, compatibility with minimally invasive surgery, reduced risk in cold-welding failure, improved uniformity in bone screw axial forces, and higher plate bending stiffness. A series of finite element based numerical procedures were established to evaluate the performance of the angle fixator design. Based on the numerical evaluations, a preferred interference value of 20 μm was selected for the locking of the angle fixator to bone plate. A set of Ti-6Al-4V bone plates were fabricated by using selective laser melting (SLM) additive manufacturing process. Experiments were conducted by using these plates to evaluate the lock-in torque for the interference fit, the pullout force for the assembly to separate, and the bone screw-shear induced critical moment for loosening the bone plate-to-angle fixator connection. It was shown that the lock-in torque for the interference fit is around 2.5 N·m, which is lower than the typical limit of bone screw fixation, and would reduce the risk of cold-welding. The pullout force required to separate the plate-to-screw connection is higher than 2 kN, and the remote shear induced critical moment to loosen the connection is 1 N·m. These performance indexes compare well to conventional bone plate and screw designs, and validate the design. The numerical and experimental procedures developed in this study may further be applied to investigate the performance of other new bone plate design.

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