Orthotics Impact on Leg Mechanics
The use of foot orthotics are commonly prescribed for many lower quarter conditions including running injuries, foot and ankle pain, and even low back pain. As we have described in previous posts off the shelf orthotics perform as well as more expensive custom orthotics, but overall their impact on many conditions is limited. When compared to more active approaches including Physical Therapy and exercise, orthotics fall short of manufacturer's and clinician's promises of pain relief and improved function.
A recent study out of the University of Wisconsin examined the impact of off the shelf orthotics on running mechanics (O'Conner et al. JOSPT. 2016). Authors studied 31 recreational runners in a biomechanics laboratory while running with or without a foot orthotic. In particular, the authors were interested in the amount of dynamic foot motion at the heel and mid foot during the stance phase of running. Runners were then grouped based on the amount of motion in their feet during running. They hypothesized that runners with the greatest amount of motion may benefit most from the orthotic. The results of this study show that orthotics did not significantly impact motion at the hip or knee and thus the use of orthotics based on a patients degree of foot and ankle motion is not supported.
Athletes are advised to understand the limitations of orthotics to change lower quarter running mechanics and instead work with a local Physical Therapist to correct these running mechanics.