Rocker Profile Restores Leg Progression When Walking with Orthotic Ankle Constraint

Undergraduate research presented at the 3rd Annual Prosthetic Orthotic Research Symposium, April 19, 2013 12:30 pm – 05:30 pm, Student Center Theater.Runtime: 09:35 minutes.Rocker profiles are one of the most commonly prescribed therapeutic footwear modifications. Typically, they are used to allow lower limb forward progression when ankle and foot motion are restricted by mechanical constraint (i.e. lower limb orthosis) or clinical pathology (i.e. lower limb fracture). Although rocker profiles are commonly used, their design and performance have not been clearly described. To address this need, we studied the role of rocker profile footwear and its influence on lower limb forward progression when used in combination with an orthosis designed to constrain the ankle joint. We hypothesize that healthy subjects walking with unilateral ankle-foot orthosis footwear combination will elicit no difference in the shank forward progression compared to control (no ankle constraint) during stance phase (early, mid, late). The shank forward progression was quantified as the forward and vertical components of the acceleration. Analysis of constrained and unconstrained shank acceleration for three subjects revealed no difference during mid-stance, but showed differences during early and late stance. Although there are some differences in the shank acceleration when walking with and without ankle constraint, there is no notable gait deviation between the two conditions. This supports the notion that the rocker profile designed in our laboratory functions as a biomimetic ankle-foot complex that restores lower limb forward progression when the ankle is mechanically constrained by an orthosis.Mentor: Christopher Hovork