A research team evaluated the off-loading properties of the ExoSym passive dynamic ankle foot orthosis (PDAFO) and found that it unloaded substantial force and pressure on the forefoot. The study participants also loaded the brace to a greater extent than when going unbraced, providing measurable pressure relief for patients with arthritic conditions.
The same orthopedic surgeon prescribed the PDAFO to six adult patients at the same institution between 2014 and 2018. Indications for bracing treatment included arthritic foot or ankle conditions amenable to dynamic bracing. Pedobarographic data was obtained using the Tekscan F-Scan system.
With the insole, participants were instructed to walk at a self-selected pace along a 20-meter walkway under three conditions: insole placed in between the brace and foot (over); insole placed between the brace and insole of the shoe (under); and without the brace, the insole was placed in between the foot and insole of the shoe in both limbs (without).
For assessment, forefoot and heel areas were evaluated with respect to maximal force; force x time integral (FTI); maximal contact area; maximal contact pressure; pressure x time integral (PTI); and center of force (COF) excursion. The brace reduced forefoot maximal force and contact pressures by 66 percent and 49 percent, respectively. Additionally, participants were observed to load the forefoot portion of the brace with double the maximum contact pressures compared to the unbraced foot, according to the study.
The open-access study, “Passive Dynamic Ankle Foot Orthoses Use in Civilian Patients with Arthritic Conditions of the Foot and Ankle,” was published in Foot & Ankle Orthopaedics.