Plantar Pressure Distribution in a Hyperpronated Foot before and after Intervention with an Extraosseous Talotarsal Stabilization Device—A Retrospective Study

Plantar pressure measurements have long been used by clinicians to provide information regarding potential impairments and disorders of the foot and ankle. Elevations in peak plantar pressures or a poor distribution of these pressures can be an indication of pathomechanics in the foot. Lower extremity deficits such as sensory impairment, foot deformities, limited joint mobility, and reduced plantar tissue thickness have been associated with high plantar pressures. The total pressures, pressure distribution, and peak pressures provide useful information to evaluate the abnormal functioning of the talotarsal joint. Instability of the talotarsal joint can result in excessive forces exerted on the joints and surrounding tissues in the foot that can then lead to dysfunction of the proximal musculoskeletal kinetic chain. In the present study, we performed a retrograde analysis of the pre- and postoperative measurements of the peak plantar pressures, peak forces, and area of contact between the foot and the ground during each phase of the gait cycle for 6 patients (12 feet) who had undergone a bilateral extraosseous talotarsal stabilization procedure using a type II extraosseous talotarsal stabilization device. After the procedure, a significant reduction was seen in the peak pressures (42%) over the entire foot and a significant increase in the contact area (19.7%) between the foot and the floor. This could imply that the extraosseous talotarsal stabilization procedure was effective in stabilizing the talotarsal joint complex, thus eliminating abnormal hindfoot motion and restoring the normal biomechanics of the foot and ankle complex, as indicated by a reduction and realignment of the peak plantar pressures and forces.