股骨近端骨折是造成老年人死亡及疾病的重要原因之一。對骨科醫師而言，因年齡老化造成的髖部骨折及其相關治療的重要性，無疑都是相當熟悉的，藉由滑動式髖螺釘手術來固定髖部粗隆間骨折是最常使用的治療方法，主要是由於它具備操作上相當簡單，在X光底下可清楚呈現，可分散骨折處承受的力道及失敗率低等多項優點。
　　根據統計，滑動式髖骨釘術後的合併症約4﹪至16﹪，主要是髖螺釘穿透股骨頭，有關滑動式髖骨釘方面的研究，無論是臨床上或生物力學上的，幾乎都著重在探討髖螺釘釘在股骨頭內的最佳位置或骨釘骨板間的最佳夾角，幾乎很少有論文提及到骨板的合適長度，根據製造商的統計及臨床上骨科醫師一般的使用習慣，大部份都是使用135度4個洞的骨側板。
　　有趣的是，在1955年由Schumpelick及Jantzen首度提出，將滑動式髖骨釘應用於臨床上的報告顯示，當時是使用2個孔的骨側板，在後來的數十年間，骨科醫師習慣於4孔骨側板使用的原因有可能是因為有很多例的骨釘穿透股骨頭及穿透到髖關節的合併症，而逐漸演變成的。但很明顯的，手術中使用較長的骨側板會造成大範圍的軟組織破壞，手術時間較長，失血量較多及較大面積的骨膜剝離，理論上，綜觀這些因素會增加老年病人的住院時間及其致病率。
　　我們的研究即是針對雙孔骨側板滑動式髖螺釘，在臨床上使用的結果及針對力學上失衡的案例做生物力學上的評估。

　　Fractures of the proximal end of the femur are a major source of mortality and morbidity among the elderly. The prevalence of intertrochanteric fractures and the importance of their treatment is well understood by orthopaedic surgeons. Surgical treatment of intertrochanteric fractures is most commonly facilitated by the use of sliding hip screw device because of the ease of apply intraoperatively, good load-sharing capability easy fluoroscopic image control, and relatively low mechanical failure rate.
　　Complication rate after dynamic hip screw fixation reported by various authors range between 4 percent to 16 percent, predominantly associated with cut-out of the lag screw through the femoral head. So, most of the clinical and biomechanical studies concern the uses and advantages of sliding hip screws is directed toward the correct or best placement of a sliding screw in the femoral head and the best angle of screw insertion. Little to no attention has been directed toward the appropriate side plate length . According to the statement of the manufacture company, the most commonly sold side plate is the 135 –degree four-hole side plate variety.
　　Interestingly, in the first clinical report of the sliding hip screw in the U.S. literature by Schumpelick and Jantzen in 1955, the side plate reported was a relatively short two-hole variety. How we evolved to the longer side plate, most of them are at least 4-hole side plate length, is uncertain. Longer side plate placement will require larger dissection, longer surgical time, increased blood loss, more periosteal stripping. Theoretically, these factors will increase the morbidity and hospital stay of the geriatric patient.
The purpose of the present study is to report the results of clinical use of 2-hole side plate sliding hip screw and evaluate the biomechanical factors responsible for mechanical failure.

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