Flexible flatfoot is a condition in which the arch of the foot shrinks or disappears upon standing. Upon sitting or when the child is on tiptoes, the arch reappears. Parents and other family members often worry needlessly that an abnormally low or absent arch in a child's foot will lead to permanent deformities or disabilities. Most children eventually outgrow flexible flatfoot without any problems. The condition usually is painless and does not interfere with walking or sports participation.
A flexible flatfoot has normal muscle function and good joint mobility and is considered to be a variation of normal. As the child grows and walks on it, the foot's soft tissues tighten, shaping its arch gradually. Flexible flatfoot often continues until the child is at least age 5 years or older. If flexible flatfoot continues into adolescence, the child may experience aching pain along the bottom of the foot. A doctor should be consulted if the child's flatfeet cause pain.
To make the diagnosis, the doctor will examine the child to rule out other types of flatfeet that may require treatment. These include flexible flatfoot with a tight heel cord, or rigid flatfoot, which is a more serious condition.
The doctor will look for patterns of wear on the child's everyday shoes. Tell the doctor if anyone else in the family is flatfooted, as this may be an inherited condition. It is important to know about any known neurological or muscular disease in the child.
The doctor may ask the child to sit, stand, raise the toes while standing, and stand on tiptoe. He or she will probably examine the child's heel cord (Achilles tendon) for tightness and may check the bottom of the foot for calluses.
Treatment for flexible flatfoot is required only if the child is experiencing symptoms of discomfort from the condition.
If the child has activity-related pain or tiredness in the foot/ankle or leg, the doctor may recommend stretching exercises for the heel cord.
Occasionally, surgical treatment will be necessary for an adolescent with persistent pain. A small number of flexible flatfeet become rigid instead of correcting with growth. These cases may need further medical evaluation.