采用CT测量建立人体膝关节在静态下伸直位、名义屈曲度30°、60°、90°和120°不同屈曲位的三维点云模型,通过三维图像配准和坐标变换进行人体膝髌股关节相对运动分析.采用三维图像配准技术,将不同屈曲位的膝关节三维图像放入同一坐标系中,将不同屈曲位的膝髌股关节股骨和髌骨的物体坐标系建立在同一位置和方向上,从而避免了在不同坐标系下分别建立物体坐标系所带来的误差.建立人体膝髌股关节各骨组织的正交坐标系,通过运动坐标系坐标变换得到人体膝髌股关节相对运动的数据.研究结果有助于正确认识人体膝髌股关节的运动、优化全膝关节置换髌骨假体的设计并改善手术效果.
The 3D point clouds models of an in vivo human knee from several flexion knee using computed tomography were reconstructed, and 3D image registration and coordinate transformation technique was applied to quantify normal, in vivo human patello-femoral joint kinematics. By using the technique of 3D image registration, different models of several flexion knee positions were aligned to the same coordinate system. As for each model of the knee, object coordinates of femur and patella were built on the same location and direction in comparison with individual femur, tibia and patella. Consequently, the error of constructing the object coordinate system in various coordinate systems can be avoided. Meanwhile, improved orthogonal coordinate systems were built on femur and patella. After orthogonal coordinates were built on each part of the knee, the Euler angle coordinate transformation was applied to acquire the data of the patello-femoral joint relative kinematics. It can be used to optimize the prosthesis design of patella and operation of total knee replacement.