An Application of the Automatic 2D-3D Image Matching Technique to Study the in-vivo Knee Joint Kinematics before and after TKA

摘要

There is an increasing need of the accurate comparison of the in-vivo joint kinematics before and after the knee replacement, which is still a challenging issue in technique. In this paper, we applied an automatic 2D-3D image matching technique to study the knee joint of a Chinese patient before and after a traditional posterior-stabilized TKA. An imaging system of Shimadzu's fluoroscopy was used to acquire the 2D images, which were recorded in sagittal view during a dynamic activity of knee flexion. The algorithm of automatic procedure was tested 20 times for a single pose to examine the repeatability. The result shew that the in-plane repeatability was within 0.5 mm and 1.5°, and the out-of-plane repeatability was within 5.4 mm and 1.7°. The dynamic kinematics was calculated based on the series of reproduced spatial positions of the knee joint. The result of the pre and postoperative patellar flexion in patellofemoral joint was similar. In sagittal view, less sinking of the patella and variation of the angle of patellar tendon were observed in TKA knee after 30° of knee flexion. This technique will be applied to study more knees of the healthy, abnormal and TKA patients in China.