High-top athletic shoes are frequently chosen to augment
ankle support because they may provide increased
resistance to ankle rotation in the frontal plane.29 The increasing
cost of these shoes may be justified if they decrease
ankle injury rates,10 although not all studies support this
finding.’ The lack of concordance on this issue may be
partly explained by the fact that in the neutral ankle position
in the frontal plane these devices probably offer little
or no passive resistance to a ground-reaction force acting to invert the ankle. It is only as ankle inversion increases
from the neutral position that passive shoe resistance rises.
If the external moment increases at a faster rate than that
of the passive resistance of the shoe, ankle passive tissues,
and active resistance from muscle activity, then a large
increase in inversion rotation can occur as a result of a
small increase in moment. This would be an example of mechanical
instability and could result in soft tissue or bony
injury. A primary focus of this study was to determine the
level of resistance offered by a three quarter-top basketball
shoe early in this sequence of events, when the ankle joint is
close to its neutral position in the frontal plane.