Skeletal lower extremity motions during running

The purpose of this study was to quantify the effects of (i) medial foot orthoses and (ii) shoe sole modifications (lateral heel flares) on skeletal movements during the stance phase of running, to compare (iii) barefoot versus shod running, and to describe (iv) the movement coupling between selected segments of the lower extremity. Marker triads were attached to intracortical bone pins inserted under standard local anesthesia into the calcaneus, tibia and femur of five subjects. The subjects ran barefoot, with a normal shoe, with three shoe soles and with two orthotic modifications. The trials were recorded during the stance phase of running using three high speed cine cameras operating at 200Hz. Tibiocalcaneal and tibiofemoral movements were calculated using three-dimensional marker reconstruction and a joint coordinate system approach.

Medially placed foot orthoses did not substantially change tibiocalcaneal movement patterns during running. Differences between subjects were significantly larger (up to 100) than between orthotic conditions (1° to 4°; p < .01). Significant orthotic effects across subjects were found only for total internal tibial rotation (p < .05). Lateral heel flare effects on tibiocalaneal movements were small and unsystematic. Total shoe eversion and shoe eversion velocity were found to be approximately twice as large as the respective bone eversion. Tibiocalcaneal movements were similar in barefoot running compared to running with shoes. Only one specific shoe modification (posterior orthosis) showed significant (p < .01) differences to barefoot running, all other test variable comparisons were not significant. Movement coupling was observed between various segments at the lower extremity (shoe-calcaneus, calcancus-tibia, and tibia-femur) and was found to be subject and shoe dependent. Generally, movement coupling varied in distinct phases between heel strike and take-off. It was suggested that the input to calcaneus-tibia coupling was from distal to proximal, and that to tibia-femur coupling (at least partially) from proximal to distal.

A number of possible factors were identified that may have influenced the results, including the test shoes used, the shoe sole construction, and the application of local anesthesia and its possible influence on proprioceptive feedback.

The results of this in-vivo study suggest that (a) orthotic effects and effects of shoe sole modifications on skeletal movement patterns are small and subject specific and that these effects may be mechanical as well as proprioceptive, (b) calcaneal and tibial movement patterns may not be changed substantially when using shoes compared to running barefoot, but differences may occur when extreme shoe modifications are used, (c) movement coupling varies between heel-strike and take-off and takes place in phases between various segments of the lower extremity during the stance phase of running.