Flat Feet

Flat foot (pes planus) is when the inner arch of the foot collapses on standing and most of the sole touches the ground. Parents often notice it and worry. Yet most flat feet, especially in children, are part of normal development.

Flat feet in children

Babies and young children have fat pads in their soles and more flexible ligaments, so the arch naturally looks flat. The arch usually develops gradually up to the age of 6-8.

Flexible flat foot

The arch disappears when the child stands but appears when rising on tiptoe or sitting. It is usually painless and needs no treatment.

Rigid flat foot

The arch does not appear either standing or on tiptoe, and foot movement is limited. It may be caused by structural problems such as tarsal coalition (a congenital fusion between foot bones) or congenital vertical talus, and should always be assessed.

When should it be checked?

• Pain in the foot, leg or knee
• Tiring quickly and avoiding long walks
• Flat foot on one side only
• A stiff foot with limited movement
• Shoes wearing quickly on the inner edge
• A tight Achilles tendon and toe walking

Flat feet in adults

The most common cause of flat foot that develops in adulthood is failure of the tibialis posterior tendon, which supports the arch. It starts with pain and swelling on the inner side of the ankle, and the arch gradually collapses. Treated early, its progression can be slowed.

Diagnosis

The foot is examined standing and on tiptoe, and joint movement and Achilles flexibility are measured. Standing X-rays, CT or MRI are used when needed.

Treatment

• Painless flexible flat foot: No treatment needed. Walking barefoot on different surfaces and staying active are encouraged.
• Painful flexible flat foot: Achilles and calf stretches, foot-strengthening exercises, supportive insoles and suitable shoes.
• Rigid flat foot and tarsal coalition: Surgery may be needed if symptoms continue.
• Adult flat foot: Orthoses and physiotherapy; tendon and bone correction surgery in advanced cases.

Advice for children

For children with flexible flat feet, being active, walking barefoot on different surfaces (sand, grass, carpet) and playing games that work the foot muscles support foot development. Picking up small objects with the toes, walking on tiptoes and heels, and skipping are simple activities that help. Choose light shoes with flexible soles that fit the child’s foot well.

Tarsal coalition

Tarsal coalition is a congenital bridge of bone, cartilage or fibrous tissue between foot bones. It usually starts causing symptoms between the ages of 8 and 16, as ossification progresses. Recurrent ankle sprains, pain on the outer side of the foot and a rigid flat foot are typical. CT or MRI confirms the diagnosis. If symptoms do not settle with non-surgical treatment, the bridge can be removed surgically.

Stages of adult flat foot

Tibialis posterior tendon dysfunction is progressive. Early on there is only pain and swelling along the tendon and the foot shape is preserved. As it progresses, the arch collapses, the heel shifts outwards and the toes point outwards. In advanced stages the joints stiffen and arthritis develops. Treatment follows the stage: braces and physiotherapy early, tendon transfer and bone correction in the middle stage, and joint fusion in advanced stages.

Choosing insoles

Off-the-shelf insoles may be enough for mild symptoms. For painful feet or marked deformity, custom insoles made after examination and measurement are more suitable. Shoes must also be wide and deep enough to take the insole.

Frequently asked questions

Should I buy orthopaedic shoes for my child?

There is no evidence that orthopaedic shoes change arch development in painless flexible flat feet. Comfortable, flexible, well-fitting shoes are enough.

Is flat foot a barrier to sport or military service?

Painless flexible flat foot is usually not a barrier to sport. Official assessments follow the criteria of the relevant institutions.

Do insoles correct flat feet?

Insoles can reduce pain by supporting the foot, but they do not permanently change the bone structure.

Do flat feet affect the knees or back?

There is no strong evidence that painless flexible flat feet cause knee or back problems. With painful flat feet, walking may change, which can strain other joints.

Are flat feet inherited?

There can be a family tendency. Children with a family history usually have flexible, painless flat feet too.

At what age is flat foot surgery done?

In children, surgery is only considered for painful feet that do not respond to non-surgical care, usually after the age of 8-10. In adults, the decision depends on symptoms and the stage of the condition.

Do flat feet affect walking?

With flexible, painless flat feet, walking is usually normal. Painful or rigid flat feet may cause early tiredness and an abnormal gait.

The information on this page is general and does not replace an examination. An examination is needed to decide which treatment suits you.