全人工腕掌關節置換手術是骨科常見的重要手術之一。臨床顯示，醫師往往憑藉自身的經驗以及技術的累積進行手術，而實習醫師因缺乏大量手術訓練因而造成技術不成熟，如何使缺乏手術經驗之醫師在手術過程中提升手術品質與降低病患風險是非常重要的。故本研究利用電腦輔助設計與逆向工程的方法，建構手術訓練用之仿真手模型，使醫師在進行手術訓練時能夠更加精確的模擬出手術觸感與術前評估規劃，進而提升醫師臨床技術與手術成功率。
本研究為了做出手部複雜幾何之模型，特別引用3D列印技術以及矽膠灌注成型技術製作符合手術訓練之仿真手。製造過程首先使用電腦斷層掃描(CT)取得到骨骼和皮膚輪廓影像，再利用CAD軟體結合CT影像設計出仿真手之模具、骨頭以及其對位板，並以3D列印技術製作出上述CAD模型，再將對位板精準對位在骨頭以及模具上，校正骨頭與模具之相對位置。本研究為了符合臨床需求，利用乳膠材料黏著在兩骨間的關節上當作關節囊，最後以矽膠灌注成型之技術，將矽膠灌入已有骨頭之定位模具以當其皮膚並將骨頭完全包覆在內，最終完成仿真手。
在完成仿真手之後，還需將其仿真手進行電腦斷層掃描並與原骨骼之CT影像做骨頭位置比對以驗證仿真手是否與真實CT影像相符，並請具有臨床經驗之醫師親自操刀測試。為了符合手術訓練之成本，本研究還針對不同類型與價格的3D列印機所製作之模型，以相同製作仿真手過程進行模型重製並將兩種列印方式進行探討與研究。

Total Carpometacarpal (CMC) joint replacement is one of several efficacious orthopedic surgical treatments by which to restore functions of finger joints. Surgeons have depended on their clinical experience and on technology when performing such operations. However, it is important to enhance surgical quality and decrease the surgical risk for interns. Therefore, this study uses computer-aided design (CAD) and reverse engineering to construct a model of an artificial hand. The surgical training can accurately simulate a pre-estimation of surgery and surgical touch to promote the clinical skill and the surgical success rate of surgeons.
For geometrical accuracy of the hand and model accuracy, this study uses 3D printing technology and injection molding technology to fabricate an artificial hand. This artificial hand can replicate the features of an actual hand during surgical training. The manufacturing process involves the use of computer tomography to obtain images of bones and skin. Then, the molds of the artificial hand, the bones and plate are designed using CAD software. The above models are fabricated with 3D printing technology. The completed plate is orientated on the mold and the bones. The relative position of the bones and molds is then adjusted. The latex material can adhere to the bones of a joint as a joint capsule in order to meet clinical requirements. Finally, silicone molding technology is used to pour the silicone into the molds. When the silicone is fully solidified, the artificial hand is completed.
After the artificial hand is completed, computer tomography is used to scan the artificial hand. The position of the bones in the original CT image is compared with the position of bones in the prosthetic CT image. Then, the artificial hand is dissected by a surgeon who has clinical experience. In order to meet the cost of surgical training, this study is aimed at models that are fabricated according to different types and prices of 3D printers. Two types of 3D printing are investigated that the reproduction of models in the same procedure of fabricating artificial hand.

Keywords: Rapid prototyping, Surgical training, Injection molding

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