人工髖關節周圍骨折越來越常見，臨床上常以骨板搭配骨釘及鋼線纏繞固定，但骨折固定術後仍發現有骨板斷裂或固定系統鬆脫等問題。觀察發現: 雖為同類型斷裂模式，仍有不同的骨折斷裂走向，固定時骨釘數與鋼線數搭配模式雖依醫師經驗判斷，衍伸出生物力學議題：1.不同斷裂走向對骨質受力，可能有不同影響程度；2.不同的鋼線數與骨釘數搭配植入模式，可能產生不同生物力學行為。本研究利用生物力學實驗探討溫哥華（Vancouver classification）B1,B2類型骨折--包含兩種斷裂模式、兩種負載給定與多種不同固定模式進行多參數探討。
骨折常併發手術骨癒合不正,不良及固定物失敗，乃因此處有極重要的人體重力分佈區(trabecular zone)，尤其在步態站立時需傳導很大力量經過此重力分佈區。生物力學實驗曾經評估很多種固定器之使用; 股骨近端互鎖式鋼板已經開發，提供比動態加壓式鋼板螺釘更多優點，提供骨頭較強的抓力和壓迫力，避免傳統股骨骨折於骨鬆病患之不足。本研究探討傳統加壓式鋼板，互鎖式股骨近端解剖型鋼板與新型Doll miles, Cable readygrip, NCB PP fixation systems合併抗旋轉鋼板之設計。實驗採用微創、閉合復位方式探討以上五種固定器於人工髖關節周圍骨折之骨鬆病患穩定效應。實驗模型在人造股骨的人工髖關節(穩定或不穩定)周圍製造一個間距骨折，擺上上述五種固定物(共10具人造股骨)，進行動態疲勞測試以模仿人體術後三個月內之步態使用，固定器失敗或位移五毫米為實驗之終止條件，觀察以上五種固定器之穩定效果及骨釘-骨板或人工髖關節周圍之應力分佈；另外有限元素分析模型也依此建立最佳化設計，藉此提供臨床醫師使用各種固定器於人工髖關節周圍骨折之參考。

Proximal femoral periprosthetic fracture following THA is a gradually common problem occurring in recent years. Its difficulty and complexity of clinical treatment using plate and screw fixation draws many researchers’ attention. A new design, NCB-PP plate and screws, which were proposed with few discussed biomechanical property on cap-screw mechanism, was made clearer through our study. A biomechanical experiment and finite element analysis was conducted to show when the screw was fixed at zero degree, screw- cap construct has higher stiffness than that at 15 degree. Interestingly, screws fixed at 30 degree, over suggested design, has similar stiffness as zero degree. Further experiment and finite element analysis towards whole construct should be studied.

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