The current nonsurgical treatment for pediatric flatfoot includes shoe modification, inserts, and foot orthoses (FOs). However, these methods do not affect the course of flatfoot in children and have only limited evidence of correction of foot pronation. The goals of this study are 1) to describe how to design novel customized FOs using plantar pressure and fluoroscopic measurements; and 2) to assess kinematics and kinetics of the foot and ankle joint and functional outcomes at baseline and 12-month follow-up.
One child with bilateral flatfeet received trio-pressure measurements, including dynamic plantar pressure, single sensor pressures on the lateral calcaneus, and medial talar head. The two-dimensional (2D) foot motion in the sagittal plane during the stance phase using single gantry fluoroscopy was recorded. Three-dimensional (3D) surface images of the entire foot and distal lower limb were registered.
A total of 14 pressure metrics and three-dimensional (3D) foot and ankle topography were used to design the new orthoses and generate a computer-aided design model. Data from the fluoroscopic images were used to evaluate the orthotic design. Finally, two orthoses were designed and manufactured with a rapid prototype system (SLS).
The gait-based software was successfully developed to design the new orthoses. Features included use of navicular height, talar and calcaneal alignment, pressure metrics, and foot geometry. This case study had 12-month follow-up and showed that the new FOs reduced pain and improved functional outcomes.
Use of gait-based software allows a further approach directly into the rapid prototype systems for orthoses designed to address pes valgus deformity.
XUE-CHENG LIU, MD, PhD; ROBERT RIZZA, PhD; SCOTT VAN VALIN, MD; JEHAD AL-RAMAHI, BS; ROGER LYON; and MD, JOHN THOMETZ, MD, are affiliated with the Departments of Orthopaedic Surgery and PMR, the Center for Motion Analysis, Department of Orthopedic Surgery, Children's Hospital of Wisconsin, Medical College of Wisconsin, Milwaukee, Wisconsin.
Disclosure: This study has been funded by Rehabilitation Research Engineering Center (RERC) on Technologies for Children with Orthopedic Disabilities, National Institute on Disability and Rehabilitation Research (H133E100007). The authors do not have any conflict of interest to disclose.
Correspondence to: Xue-Cheng Liu, MD, PhD, Professor of Orthopaedic Surgery and PMR, Co-director of Center for Motion Analysis, Department of Orthopedic Surgery, Children's Hospital of Wisconsin, Medical College of Wisconsin, 9000 W Wisconsin Ave, PO Box 1997, Suite C360, Children's Corporate Center, Milwaukee, WI 53201; email: firstname.lastname@example.org