An AFO works by applying pressure to the structure of the foot and ankle. What makes external bracing more complex is the need to apply this pressure through the skin and its underlying tissue. The need to minimize the skin and tissue injury as a result of this pressure requires an extremely accurate fit of the brace to the child and regular adjustments as the child grows. Adjustments are an important part of the treatment. When adjustments can no longer be made, AFOs must be replaced.