Kinematic Quantification of Gait Asymmetry Based on Characteristics of Angle-Angle Diagrams

Synchronized Cyclograms to Assess Inter-Limb Symmetry during Gait in Post-Stroke Patients

“…Quantitative evaluation of gait symmetry is usually performed according to the differences observed in a subset of spatio-temporal gait parameters commonly analyzed in stroke survivors (e.g., step length, single and double support duration) between the affected and non-affected limb [5,[9][10][11][12][13][14] whilst other kinematic/kinetic variables are considered less frequently [5,12,13,[15][16][17][18][19][20]. However, even though the above-mentioned approach is quite easy to implement, it presents some limitations such as the inability to identify the temporal location of asymmetry or to detect occasional events during the gait cycle and a low sensitivity and lack of standardization due to the arbitrary choice of equation and variables [5,12,15,21,22]. To overcome such drawbacks, new methods allowing for a quantification of gait symmetry have recently been developed.…”

“…In recent years, several studies have attempted to apply waveform-based analysis to assess inter-limb symmetry during gait in several neurologic and orthopedic conditions [15,16,[23][24][25][26][27][28]. The results of such studies suggest that this approach is sensitive even to relatively low asymmetries and may represent a useful complementary tool to achieve a detailed assessment of gait alterations.…”

“…This method, which was firstly proposed in the late 1960s [32], considers the angular positions of two contralateral joints simultaneously plotted in the same diagram, without considering the time axis of each curve. According to this approach, symmetry quantification can be carried out either by calculating the simple geometric properties of the curve (i.e., such as the area, perimeter, orientation, and shape) or various order moments and trend symmetry [15,16,21,30,33].…”