【作者】 崔菊；

【导师】 王海涛；

【作者基本信息】 南京航空航天大学 ， 检测技术与自动化装置， 2009， 硕士

【摘要】 交锁髓内钉的出现并广泛使用是骨折治疗领域的最大进展之一,用它来固定股骨干骨折部位的方法,可以使得患者的恢复效果比用钢板固定等方式治疗的效果好许多。但由于手术过程中固定髓内钉是在骨腔内进行的,远端锁孔位置难以精确定位,而使得手术不得不长时间在X光照射下进行,这严重威胁了医生和患者的健康。基于目前的手术方法存在上述缺点,本文提出用光电检测的方法来定位交锁髓内钉的远端锁孔,介绍了基于光斑重心的交锁髓内钉远端定位方法,通过计算交锁髓内钉变形前后其远端端面像的重心变化,计算出交锁髓内钉远端锁孔的实际变化,并建立了该定位系统。论文介绍了交锁髓内钉远端定位检测系统的原理和组成,主要包括光纤图像传输系统的设计和交锁髓内钉定位支架装置的研制,软件方面阐述了基于重心的光斑中心定位算法,在此基础上用VC++对光斑中心位置进行精确测量。为了避免二值变换引起的毛刺,先使用改进的阈值变换,再使用一种直观的画圆的方法,把光斑框起来求重心位置。通过实验测量和数据分析得出,交锁髓内钉远端的位移与光斑重心的位移成一定的线性关系。根据这个线性关系和光斑重心的位移则可以推出骨腔中髓内钉的远端位移,进而可以锁钉。最后进行实验验证,使交锁髓内钉远端受力产生形变,光斑位置即产生相应的移动,通过软件计算出光斑的位移量,根据已知的标定曲线即可以推出理论髓内钉远端形变量,并与实际的形变量作比较和分析。结果表明该系统定位锁孔误差小于0.1mm,满足系统指标要求,具有较高的稳定性。更多还原

【Abstract】 The appearance of interlocking intramedullary nails and its widely use is one of the fastest developments in the field of in treatment of the fracture. The recuperate effect for the sufferer of using it in treatment of the femoral shaft fracture is better than others as armor plates and so on. But as the process of fixing locking intrameduallary nailing on operation is going inside the femur, it is hard to accurately make sure the position of distal lockhole, so the operation has to be processed under the X-ray for a long time and it is harmful to the doctor’s and the sufferer’s health deeply.Because of the main defections which exist in fracture surgery nowadays, we present a novel distal location method of photoelectric detection technology and establish the system based on gravity center of light spot. The actual position of distal lockholes for interlocking intramedullary nails can be obtained through computing the change of gravity center of the light spot before and after deformation.We describe the principle and component of the measurement system. In hard line, we mainly design on optical fiber image system and stent positioning system. The first object is to get the gravity center of light spot after image acquisition in software, so we exploit a real-time system based on VC++ to measure the gravity center of light spot. During image processing, a modified threshold transform of image is used to avoid the defect through the binary transform. A circle is drawn directly around the light spot to get the gravity center. In addition, a lot of measuring experiments are performed in the laboratory. We can draw the conclusion based on the experimental data which constitutes a certain linear relationship between the displacement of distal end and the displacement of light spot. According to this linear relationship and displacement of light spot, the remote displacement of interlocking intramedullary nails in femur can be obtained.To subject to a test, we can get the precision of system by comparing and analyzing theoretical deformation and practical deformation of distal end for interlocking intramedullary nails. The quantitative analysis of the result shows that the absolute error of orientation can be less than 0.1mm. It can meet the requirement of the measuring system. The measurement system has higher stability.更多还原