Foot Biomechanics Theory

Each of the 26 bones in the foot serves a purpose, but rather than focus on the function of each bone in relation to its neighbor we define the system as a whole.  We look at the inputs to the system (body weight, foot type and activity levels) and focus on measuring and evaluating the outputs (improved efficiency, function and pain).  Rather than debate the competing biomechanical theories of foot position we aim to consider the aspects of each one that make the most sense to us as we view human movement. Our goal is to understand body function and the principles that govern joint mobility and stability then apply it to the foot.  We are focused on research, with ongoing projects that will attempt to answer the prevailing scientific questions of the day including foot really moves when we walk, and how that motion is affected by foot wear, walking surfaces and foot orthotics.

The foot can be thought of in a simple sense as a spring.  An optimal foot provides mechanical advantage for work through both tension and compression.

Because the work performed by an object is a function of its potential energy, the more potential energy stored in a system, the more work that can be performed.

Bioengineers know that strength comes not just from contractile tissues, but the elastic components of tissues as well. Like the force exerted by a spring, it is dependent on the distance tensioned or compressed.  As the foot pronates, the plantar tissues are stretched a distance that builds up potential energy. We can use that energy as long as the tissues are not stretched beyond their capacity to reform.  Starting the foot in a position that maximizes these travel distances and then subsequently controlling pronation is crucial.  The best way to optimize foot function is to maximize the distance over which it can absorb and produce energy while taking advantage of the elastic tissues for power.