Pediatric Flatfoot: A Common Kids’ Foot Problem

One of the greatest gifts of youth is accelerated growth. Part of this mind-boggling growth is the ability to change. Besides the rapid changes you see in a baby’s face (especially when they get teeth), their bones are rapidly evolving – especially in their feet. 

It is astounding to see an x-ray of an infant’s foot. It appears that most of the bones are missing. In reality they are present but in a cartilage state and invisible on x-ray. During infancy, bones are similar to Play-Doh and can be molded and changed.

The ability to change provides us with good and bad news. Let’s start off with the bad news: The bones will develop in a tilted position if the foot rolls inward, like a flat foot. The good news is if we control the position of the rearfoot, they will grow in a straight vertical position.

Are these your people? 

There is more good news and bad news. 

Again with the bad news: if generations before you have flat feet, then you have a great chance of your children  inheriting this. The good news, as I said earlier, is with the proper and adequate control of bone growth, these changes can be nipped in the bud and prevented.

I find it is very helpful to have both parents and grandparents at a child’s initial flat foot evaluation. Looking at a foot from the previous 1 or 2 generations gives a high predictability for foot deformities. 

If I see no deformity or symptoms in the parents and grandparents, my level of concern for future problems is reduced. My spider senses will be on full alert if I see foot and ankle deformities or hear a history of symptoms from the parents and grandparents. 

There is a strong and common connection between a child’s flat feet and adult foot deformities. Few children inherit a deformity, but a child will inherit the mechanics that will create the deformity later in life. This delay is a tribute to how well and long  the foot works under duress. The majority of problems show up after the third, fourth or even fifth decade of life.

What is as cute as a baby’s foot?

Even Anne Geddes cannot make a baby’s little piggies any cuter. 

That adorable pudgy appearance of an infant foot is from a fat pad on the arch. This will make every baby’s foot look flat, so a good assessment of foot function should not be made until the baby is two years old. 

There are two things that get my attention in an infant’s foot. Unfortunately these are not cute. The first thing is more than 10 toes. The second is a very curved or “C” shape of the outside part of the foot. The second problem is called a metatarsus adductus. This is one third of the club foot deformity. This can be a BIG deal. A mild to moderate metatarsus adductus can be treated with gentle positional therapy.

What four words do you never want to hear? 

There are some things your child will outgrow. These hopefully include “the terrible twos”, diapers, and sticking dirty things in their mouth. 

But be cautious if you hear “they will outgrow this” if it involves metatarsus adductus or excessive pronation. If this diagnosis is missed, it can wreak havoc on the adult foot and there may be a high price to be paid decades down the road. 

“Growing like a weed” is good

The foot has 25 percent  of all the bones in the body and an adult x-ray looks pretty busy with so many parts. In a child’s foot it appears like someone took an eraser and removed most of the bones. 

The bones are actually there, but very difficult to see on x-ray because they are mostly cartilage. The bone will become more visible as it calcifies. 

The early bones and growth plates (see service area about Severs disease) grow fast and are very soft. That means they will bend before they break and when they bend for an extended time, will stay in that position. This is exactly what happens in the foot when an infant walks too early with flat feet. 

“I’m tired. Mom, pick me up!”

Infants and children definitely do not like pain. How idyllic would a child’s life be if they never cut teeth or had an ear infection? After those two experiences it is no wonder that a child will elect to stop activity to avoid pain. 

Those sly and manipulative children will ask to be picked up early during a long walk. They stop playing in the group before the other children. And worst of all, they sit down during a soccer game when all the other players are running to the opposite end of the field (although this could also be from boredom). 

A pronating foot works harder, uses more energy, and tires out quickly. This would be the difference between walking 5 miles on pavement with normal feet versus walking 5 miles on sand with flat feet. That is a whopping difference in energy expenditure. You may not hear specific complaints about any foot pain coming from your child, but you may see the effects of early fatigue.