Effects of foot orthoses on skeletal motion during running

Objective. To quantify the effects of medial foot orthoses on skeletal move ments of the calcaneus and tibia during the stance phase in running. Design. Kinematic effects of medial foot orthoses (anterior, posterior, no support) were tested using skeletal (and shoe) markers at the calcaneus and tibia. Background. Previous studies using shoe and skin markers concluded that med ially placed orthoses control/reduce foot eversion and tibial rotation, How ever, it is currently unknown if such orthoses also affect skeletal motion at the lower extremities. Methods. Intracortical Hofman pins with reflectiv e marker triads were inserted under standard local anesthetic into the calc aneus and tibia of five healthy male subjects. The three-dimensional tibioc alcaneal rotations were determined using a joint coordinate system approach . Eversion (sketetal and shoe) and tibial rotation were calculated to study the foot orthoses effects. Results. Orthotic effects on eversion and tibial rotations were found to be small and unsystematic over all subjects, Differences between the subjects were significantly larger (p < 0.01; up to 10 degrees) than between the or thotic conditions (1-4 degrees). Significant orthotic effects across subjec ts were found only for total internal tibial rotation, p < 0.05). Conclusions. This in vivo study showed that medially placed foot orthoses d id not change tibiocalcaneal movement patterns substantially during the sta nce phase of running.