Flat Foot

A flat foot is one where the arch on the inner side is low or absent, so more of the sole contacts the ground when standing. Many people have flat feet, have always had them, and never experience any difficulty — in that situation no treatment is needed.

What matters is whether the foot is painful, and whether the shape is changing over time.

Flexible and rigid flat feet

• Flexible flat foot: The arch appears when standing on tiptoe or when the foot is not bearing weight. This is the common type, often lifelong, and frequently causes no symptoms at all.

• Rigid flat foot: The arch does not appear regardless of position. This is less common and more likely to be associated with an underlying problem such as arthritis, an old injury, or an abnormal connection between bones present from childhood.

Flat feet that develop in adulthood

An arch that flattens over time in an adult, particularly on one side, is a different situation from lifelong flat feet. The most common cause is failure of the tibialis posterior tendon, which supports the arch. This is often accompanied by pain along the inner ankle and a gradual change in the shape of the foot.

A foot that is changing shape is worth assessing, because treatment options are broader while the deformity remains flexible.

Symptoms

1. Aching: Along the inner arch or inner ankle, often worse after prolonged standing or walking.

2. Tiredness: Feet fatiguing more quickly than expected.

3. Change in shape: The arch lowering, or the heel appearing to drift outwards when viewed from behind.

4. Shoe wear: Uneven wear, or shoes becoming uncomfortable.

5. Outer ankle pain: In more advanced cases, as the heel drifts and the outer side becomes compressed.

Treatment

Most flat feet need nothing at all. Where they are symptomatic, non-surgical treatment is effective for many people:

• Custom orthotics to support the arch

• Supportive footwear

• Physiotherapy to strengthen the supporting muscles and tendons

• Bracing in more advanced cases

• Activity modification and weight management where relevant

Surgery is considered where the foot is painful, the deformity is progressing, and non-surgical measures are no longer controlling symptoms. Reconstruction is planned individually and may involve realigning bone, transferring a tendon, and occasionally fusing specific joints.

Dr Janan's approach

Dr Janan Chandrananth completed fellowship training in Bristol and in Tokyo under Professor Satoru Ozeki, past president of the Japanese Society for Surgery of the Foot, where joint-preserving and reconstructive techniques are a particular focus.

The great majority of flat feet do not require surgery. Where assessment is worthwhile is when a foot is painful, or when its shape is changing.