骨髓內釘固定術為長骨骨折的主要治療方式之一，骨髓內釘經由股骨頸旁植入骨髓腔後貫穿斷骨，並於兩端以螺絲將其與斷骨固定。但在植入過程中骨釘受骨髓腔形狀影響形變，使遠端(膝蓋側)螺絲固定孔方位改變，必須靠拍攝大量C-arm X光影像來確認其位置，造成大量輻射劑量與拉長手術時間的問題。本研究目的為解決遠端固定孔的定位與提供鑽孔輔助，所開發的遠端固定孔定位演算法，只利用一張C-arm影像即可計算出兩個遠端固定孔的方向與位置。而鑽孔輔助則是利用所開發的導航軟體引導主動或被動式鑽孔輔具對準計算出的固定孔方向，使醫師可以快速將鑽孔器械對準固定孔，並在鑽孔過程維持鑽孔路徑的穩定。經由65組的真實骨釘定位誤差實驗，結果固定孔中心位置誤差平均為1.06毫米、其軸線方向的平均角度誤差則是2.89°，另外也進行了10個鑽孔導航案例，都可以成功鑽穿固定孔。被動式輔具基於定位演算法結果進行可用性測試，顯示平均60.2秒完成輔助鑽孔對位，可增加對位效率與穩定性。主動式機械臂定位則達到平均位置誤差2.31毫米、方向誤差2.84 (36例)，所有案例皆能成功鑽孔。上述驗證實驗證明本研究提出之導航系統可以有效解決骨髓內釘遠端固定術的鑽孔定位精準度、手術耗時與大量輻射暴露的問題。;Intramedullary nailing is a common treatment for long bone shaft fracture. In the process of intramedullary nail implantation, the intramedullary nail may become deformed due to the shape of the medullary cavity. Thus, the surgeon requires to take a large number of C-arm X-ray images to validate the positions and directions of locking holes. In this study, we developed a positioning method for the positioning of distal locking holes. This method calculates the center positions and axial directions of parallel distal locking holes based on only one intraoperative C-arm image. A passive and an active (robot arm) assistive devices integrated with a navigation system for prompt positioning of distal locking holes and stable guidance and support of the drill are also introduced. To validate the proposed method, a total of 65 positioning tests were proceeded. The average center position error was 1.06 mm while the average axial direction error was 2.89°. Also, 10 sawbone drilling tests were conducted, in which the drill passed through the locking holes successfully. Under the guidance of the navigation system, the users could manually adjust the passive device to align the positioning probe with the locking hole within an average 60.2 seconds based on 20 test cases. In 36 test cases, the active device automatically aligned the positioning probe with the locking hole within an average error of 2.31 mm in position and 2.84° in direction. The experiment results indicate that the proposed positioning method and passive/active drilling assistive devices can accurately position the locking holes and significantly reduce operation time and radiation exposure.
