Reha Kongresse 2018


Effects of speed and mode of gait on navicular kinematics during the gait cycle

P. Eichelberger1, D. Studer1, J. Pohl1, F. Krause1, H. Baur1 (1Bern)

Walking and running, gait speed and foot strike pattern influence the ground reaction force. Since the foot must counteract these forces, foot kinematics possibly also depend from these parameters. Studies which already explored such relationships focused only on discrete kinematic features (e.g. navicular drop) but did not consider complete kinematic time-series.
Navicular kinematics were assessed in 22 healthy participants with a 3D motion capture system at 3, 4.3 +/- 0.5 (self-selected) and 6 km/h (G3, Gself, G6) and running at 6, 9 and 12 km/h (R6, R9, R12) on a treadmill.
For the walking conditions, the medial longitudinal arch showed patterns of caudally dropping and medially bulging followed by cranially rising and laterally bulging with deflection points between 67% and 78% ST. For running, the deflection points occurred earlier, between 50% and 60% ST. Maximum caudal displacements during stance measured from foot strike were 5.4, 5 and 3.4 mm (G3, Gself, G6) and 7.0, 8.2 and 8.7 mm (R6, R9, R12). The respective medial displacements were 4.2, 4.2 and 3.6 mm (G3, Gself, G6) and 4.6, 5.5 and 6.0 mm (R6, R9, R12). Reduction with increasing walking speed and increase with increasing running speed of caudal and medial displacement in the time intervals that contained the respective maxima was significant. A faster caudal movement during terminal swing and early loading response and a faster and earlier cranial movement during terminal stance were observed for increasing walking speed. Faster caudal and cranial movements became primary evident around 30% and 85% ST, respectively, for increasing running speed. Similarly, faster medial and lateral movements were primary observed around 20% and 80% ST.
Discussion et conclusions
Reductions in the maximum caudal and medial displacements during walking came primary from a reduced arch height and a more medial arch bulging at initial contact and not from an increased maximum arch flattening or medialization during stance. Contrary, increased maximum arch flattening and medialization during stance but not changes in cranio-caudal or medio-lateral position at initial contact were the primary reason for increased maximum caudal and medial displacement during stance when running.
Importance pour la pratique
Since the study found that walking and running speed affect midfoot kinematics at various instances of the gait cycle, it is recommended that assessments should not be reduced to single parameters of kinematic outcomes, like for example maximum excursion.