The center of pressure index in the evaluation of foot orthoses in shoes.

The objective and quantitative measurement of the effect of orthoses on the foot is important in evaluating orthosis design, negative casting techniques, orthosis materials, and relative clinical outcomes. The center of pressure pattern is the centroid of the pressure distribution at a series of moments in time as ground reaction is applied over the plantar surface of the foot. This article describes methods to obtain this index and how to apply this information to the evaluation of foot orthoses.