Fig 1.
Running phases with maximal knee flexion and centre of pelvis vertical movement as a function of time.
The top panel is a schematic representation of a human running in sagittal plane with contact and flight phases. CP represents the centre of pelvis and α the maximal knee flexion during stance for the affected and the non-affected leg (AL, NL). The lower three panels show the CP height, vertical speed and vertical acceleration measured during an overground (OG) gait cycle for one KOA patient. The vertical speed variance corresponds to the difference between minimal and maximal vertical speed during stance (illustrated for both AL and NL). Note the larger vertical movement and speed variance for NL.
Fig 2.
Kinematic parameters side dependency for OG and TM ground.
A) Overall results of the kinematic parameters for overgound (OG) and treadmill (TM) running. NL refers to the non-affected leg and AL to the affected leg. Boxplots show the results over all subjects. For each boxplot, the middle line represents the median value, the lower and upper limits represent the interquartile range and the error bars indicate the range and the plus signs denote outliers. Stars (*, **, ***) indicate significant differences (p<0.05, p<0.01, p<0.001) between NL and AL. Note that OG the differences between the NL and the AL were larger for all kinematic parameters compared to when running on the TM. B) Difference between the NL and AL value for all parameters. With dotted lines representing full symmetry, a symmetry increase is observed for all parameters.
Fig 3.
Overall results of the Symmetry Angle for overground (OG) and treadmill (TM).
Boxplots show the results over all subjects with dotted lines corresponding to lines of full symmetry and stars indicating significant differences. We observe a Symmetry Angle decrease on TM compared to OG for all parameters, revealing a general symmetry increase on the TM.