Comparison of Predictive and Functional Marker Sets in motion Reconstruction of Knee Joint, During Normal Gait

There are various methods for motion reconstruction using stereophotogrammetric cameras. The most common method is the use of predictive methods by attaching markers to anatomical landmarks. In contrast, functional methods are not depending on anatomical landmarks and use the relative motion of adjacent segments to identify the center of rotation and subsequently motion reconstruction. The goal of this study was to conduct a comparison between the predictive and functional methods to investigate the feasibility of using circle fitting algorithm in human body motion reconstruction. Six healthy subjects have been studied (three times each) using the three marker sets: plug-in-gait, cluster and circle-fitting method. However, some differences between methods were found in some signal characteristics, the results showed a high correlation Among three methods. By expanding functional methods such as circle-fitting, can be controlled many sources of errors in predictive methods and can be made a change in human movement reconstruction.