Fore- and rearfoot kinematics in high- and low-arched individuals during running.

BACKGROUND

Differences in the location and incidence of lower extremity injuries have been reported between high and low arched individuals. These differences might be related to functional differences between the two foot types. In particular, the characteristics of the medial longitudinal arch may influence foot function. The purpose of this study was to investigate forefoot and rearfoot kinematics as well as tibial shock in participants with both high and low arches.

MATERIALS AND METHODS

Fifteen high arched and 15 low arched males were recruited. Tibial acceleration as well as forefoot, rearfoot and shank kinematic data were collected as participants ran at 3.5 m/s wearing gait sandals. Variables of interest included peak tibial acceleration in addition to rearfoot eversion excursion, forefoot eversion excursion, forefoot eversion velocity, forefoot abduction excursion and forefoot abduction velocity. MANOVA and effect sizes were used to investigate kinematic differences between groups.

RESULTS

Multivariate analysis revealed that foot type had an effect on the kinematic variables of interest (p = 0.04). Forefoot abduction excursion (High arched = 4.7 +/- 1.3 degrees, Low arched 3.8 +/- 1.0 degrees) and forefoot abduction velocity (High arched = 96.0 +/- 24.8 degrees/s, Low arched = 69.3 +/- 13.3 degrees/s) were greater in the high arched group. Tibial shock (p = 0.24) and other kinematic variables were similar between groups.

CONCLUSION

Clear evidence of forefoot and rearfoot motion as a shock attenuation mechanism was not found. Differences in the foot kinematics during early stance were highlighted by a smaller forefoot abduction excursion and reduced forefoot abduction velocity in low arched compared to high arched individuals. It is suggested that low arched feet may have a reduced available range of motion through which the forefoot can pass before reaching the end range of motion point.

CLINICAL RELEVANCE

Foot kinematics during early stance warrant further investigation to establish a specific link to injury risk.