基于改进迭代最近点算法的接骨板贴合性快捷计算方法

为了快速计算出接骨板在断骨表面的最佳贴合位置，以减少手术中接骨板反复调整的次数，提出了一种基于改进迭代最近点（ICP）算法的接骨板贴合性快捷计算方法。首先，由医生指导在断骨表面选取贴合区域，并利用接骨板表面点的法向量之间的夹角提取接骨板的内曲面点云；然后，在对两组点云模型进行平滑处理并采用格点采样的方式来简化点云模型后，利用点云之间的特征关系进行初始配准；最后，对接骨板内曲面点云模型进行边界及内部特征关键点提取，并采用K-维树（KD-Tree）搜索邻近点，对接骨板的特征关键点和断骨表面选取区域执行ICP精确配准。以胫骨为例进行实验，实验结果表明，所提算法相较于近年所提配准算法在保持较高配准度的同时提高了配准效率，能够实现胫骨不同受损类型与接骨板之间的快速配准，并且对其他受损骨骼具有通用性。

Rapid calculation method of orthopedic plate fit based on improved iterative closest point algorithm

In order to quickly calculate the optimal fitting position of the orthopedic plate on the surface of broken bone to reduce the repeated adjustment times of the orthopedic plate during the surgical operation, a rapid calculation method of orthopedic plate fit based on improved Iterative Closest Point (ICP) algorithm was proposed. Firstly, under the guidance of the doctor, the fitting area was selected on the surface of the broken bone, and the point cloud of the inner surface for the orthopedic plate was extracted by using the angle between the normal vectors of the surface points for the orthopedic plate. Then, the two groups of point cloud models were smoothed, and the grid sampling method was adopted to simplify the point cloud models, after these operations, the characteristic relationship between the point clouds was used for the initial registration. Finally, the boundary and internal feature key points of the inner surface point cloud model of the orthopedic plate were extracted, K-Dimensional Tree (KD-Tree) was used to search the adjacent points, so that the feature key points of the orthopedic plate and the selected area of the broken bone surface were accurately registered by ICP. Taking tibia as the example to carry out experiments, and the results show that the proposed method can improve the registration efficiency while maintaining relatively high registration degree compared with other registration algorithms proposed in recent years. The proposed algorithm can realize the rapid registration between different damage types of tibia and orthopedic plate, and it is universal to other damaged bones.