Master of Science (MSc)
Faculty of Science
Foot orthotics are commonly prescribed to runners with functional flatfoot (FFF) with the goal of restoring the medial arch of the foot. In addition, treadmills are typically used by both clinicians and researchers in order to measure the lower extremity kinematics associated with running. However the mechanism of orthotic intervention as well as the accuracy of treadmills in representing overground running remains controversial within the literature.
This thesis first compared the lower extremity kinematics between treadmill and overground running among individuals with a subtalar neutral foot type. The results indicated no significant differences with respect to rate of rearfoot angle, maximum internal tibial rotation angle and rate of internal tibial rotation between the two running surfaces. However, maximum rearfoot angle was significantly higher during treadmill running. In addition, this thesis compared the lower extremity kinematics during running between individuals with subtalar neutral and FFF foot types. The results indicated similar lower extremity kinematics during running between groups as no significant differences were found between maximum rearfoot angle, rate of rearfoot angle or rate of internal tibial rotation. However, the subtalar neutral group demonstrated significantly higher maximum internal tibial rotation angles when compared to the FFF group. Finally, this thesis investigated the effects of orthotic intervention on the lower extremity kinematics during running among individuals with FFF. The results suggest that orthotics significantly decrease maximum rearfoot angle and maximum internal tibial rotation angle during running among this population. However, rate of rearfoot angle and rate of internal tibial rotation were not affected.
These findings suggest that treadmills do accurately represent the lower extremity kinematics associated with overground running, however if clinical decisions are dependent on small changes in maximum rearfoot angle then careful interpretation should be employed when using treadmills. Individuals with FFF did not demonstrate the expected increase in lower extremity kinematics therefore further research is required to better understand the mechanism of running injury among this population. In addition, orthotic intervention may have a mechanical effect on the motion of the lower extremity however the extent and applicability of this effect should be further examined.
Cunningham, E. Anne, "Effects of Orthotic Intervention during Running among Individuals with Functional Flatfoot" (2008). Theses and Dissertations (Comprehensive). 887.