Foot orthosis design for children with Charcot-Marie-Tooth and impact on gait.

Background: Charcot-Marie-Tooth (CMT) is a progressive disease resulting in distal sensory deficit and muscular weakness. As the disease progresses, most children develop a cavovarus foot deformity. Foot orthoses (FO) are widely prescribed in CMT to support the foot and improve gait, but there is a lack of guidelines for their conception. The aim of this pilot study was to report the methodology used for the design of FO (FOmax) based on an evaluation of foot deformities and to assess its effects on gait in children with CMT.

Methods: This study included 11 children with CMT. Participants were provided with a classic pair of FO (FOclass) and a pair of FOmax. A full evaluation of foot deformities was performed, and a decision-making algorithm was used for the FOmax design. A gait analysis was performed with both FO after 3 months of wear.

Results: Wearing FOmax compared with FOclass increased walking speed, step length, and single stance time. Hip flexion/extension range of motion during stance also increased. The pressure-time integral decreased on the lateral midfoot with FOmax.

Conclusions: These results suggest that the FOmax, based on the algorithm, offers benefits for walking in children with CMT. The increased step length could be related to the increase of hip range of motion. The increase in walking speed and single support times could result from a better distribution of the plantar pressure that optimizes stability during walking. The present results need to be confirmed with a larger sample.