# Influence of Body Weight Support Systems on the Abnormal Gait Kinematic
## 3 Results
### COP Movement  
Figure 6 shows the COP trajectories of all walking conditions with the mean trajectories (the butterfly curves) and standard deviation bars in both sagittal and horizontal direction. Figure 7 shows the comparisons of the COP trajectories in the sagittal direction (a), and in the horizontal direction (b), and the comparisons of the maximum displacements of COP sagittal and horizontal directions (c). In Figure 6, the trajectory of the COP in the abnormal walking case is asymmetrical between the left side and right side. The improvement of the COP trajectories can be observed in the case of walking under the ABWS system at 30% and 50% weight support since the trajectories are more symmetry than the case of the CW system. The COP trajectories while walking under the CW system are deformed, and the range of COP movements decreases while increasing the weight support level.  
Figure 5: Comparison of the COM trajectories: normal vs abnormal walking (**a**), ABWS and CW system unload 30% (**b**), ABWS and CW system unload 50% (**c**), ABWS and CW system unload 70% (**d**). (**e**) showed the comparison of the maximum displacement of COM in sagittal, horizontal and vertical direction. The significant value (_p_) was selected as 0.05. * and ** show that \(p\) is less than 0.01, and 0.001, respectively.  
The details analyzing of the COP trajectories are shown in Figure 7. The column (a) and (b) show the comparison of the COP trajectories in the sagittal and horizontal direction in the gait cycle, respectively. From top to bottom, column (a) and (b) show the comparison of the trajectories between the normal walking versus abnormal walking under ABWS and CW system at 30%, 50%, and 70% unloading force. In Figure 7, the COP trajectories in the sagittal plane show two peaks, which represented two times step for the left and right foot. The COP trajectories in horizontal direction commonly have two steady stages at bottom and top, which served for the left and right stance phase. The COP trajectory variances in terms of the abnormal walking condition and abnormal walking under the unload system (ABWS and CW system) are higher than the normal walking case. The shape of the COP trajectories was still maintained at 30% and 50% unloading force and more distorted at 70% of unloading force. The further quantities of the maximum displacement of COP are shown in the column (c). The COP maximal values in both the sagittal and horizontal direction of the abnormal walking condition significantly differed from the abnormal walking under the ABWS and CW system (\(p<0.001\)). During the left leg loading response, no significant difference was found of the maximum values of COP of the ABWS system and the normal walking condition in the sagittal plane (\(p=0.149\) at 30% weight support, 0.656 at 50% weight support, and 0.670 at 70% weight support). In contrast, the maximum COP values of abnormal walking under the CW system significantly differ from the normal walking condition. The significant differences could also be observed of the maximum displacements of the COP between normal walking versus abnormal walking under the ABWS and CW system during the right leg loading response in both sagittal and horizontal direction (\(p<0.001\)). However, the mean value of the maximum displacement of COP of the abnormal walking under the ABWS system was higher than the cases of using the CW system, and closer the normal walking case.