Multifactorial faulty biomechanics when running and participating in other weight bearing activity is linked to patellofemoral pain syndrome (PFPS) symptoms. Medially wedged foot orthotics are often prescribed to reduce knee and hip joint mechanics thought to increase PFPS. However, according to a study published in the February issue of Journal of Applied Biomechanics, the addition of medially wedged foot orthotics to standardized running shoes had minimal effect on knee and hip joint mechanics during running and that these effects are similar among females with and without patellofemoral pain syndrome (PFPS) symptoms.
The researchers said they believe this is the first investigation to examine knee and hip joint mechanics during running in response to medially wedged foot orthotics in injured and uninjured runners. Forty female runners-20 with and 20 without PFPS-participated in the study; they all wore the same shoes with and without orthotics. The orthotics used were 6 degree EVA medial wedges (65 Shore A hardness, Foot management, Pittsville, Maryland). Biomechanics were recorded with three-dimensional (3D) motion detectors.
With respect to the dependent variables examined in this study, the researchers concluded that the effect of medially wedged orthoses appears to be independent of standing calcaneal eversion angle. However, a small yet statistically significant decrease in hip abduction excursion and internal knee abduction moment was identified with the orthotics. Thus, although medially wedged orthoses may reduce PFPS symptoms and recovery time, a biomechanical explanation for this effect was not identified. The study also found that it is not clear if foot orthotics will benefit over-pronation.
“There’s a need to tailor orthotic prescription based on the characteristics of the runner, and this study tells us we still have not identified the characteristics that are most telling,” study co-author John D. Willson, PhD, MPT, associate professor in the College of Allied Health Sciences, Department of Physical Therapy, East Carolina University, Greenville, North Carolina, told Runner’s World.
