Flat Feet

Modulign Orthotic with its deep heel cup orthotic  provides ultimate rear foot control

What is a Flat Foot?

A ‘flat foot’ is as the name suggests a foot with a reduced arch which appears ‘flat’. A foot may be so flat the complete sole of the foot may touch the ground.

Flat Foot Pes Planus

The correct anatomical name for a flat foot is a ‘pes planus’ foot posture.

Why do people have flat feet?

There are a number of reason why people might have a flat foot

  • Hyper mobile joints

the normal ligaments and joints that support the arch of the foot may move more than they should – this means when someone stands the arch can no longer support itself and the foot collapses

Hypermobile Joints

– The tibialis posterior muscle and tendon supports the arch of the foot

Tib post dysfunction
  • Children

– It is normal for children to have a flat foot as they are developing. This is due to the increased mobility in the joints and the fact that the bones in the foot are not fully formed

  • Over weight

– Increased weight may overload the normal structures that support the arch resulting in its collapse

  • Genetics-

Sometimes having flat feet can run in the family. Generally this is due to the genetic link between ligament laxity running in families.

What is the problem with having flat feet?

There is nothing wrong with having a flat foot but in some people it can result in a number of long term problems. These include:

  • Tibialis posterior tendon overuse

This is because the position of the foot changes the demand from certain muscle groups.

Neutral FootNormal Muscle Balance Foot In a neutral foot  the muscles on the inside of the foot (invertors) work just as hard as the muscles on the outside of the foot (evertors).
Flat FootFlat foot muscle balance In a flat foot the muscles on the inside of the foot (invertors) work a lot harder to try and correct the position of the foot  – overtime this can result the degeneration of the tibialis posterior tendon.
  • Dorsal Midfoot compressionFlat foot dorsal midfoot compression Similar to a keystone bridge when the arch collapses there is greater
    dorsal compression of the midfoot
  • Sinus tarsi pain

When the foot is neutral the sinus tarsi is aligned and there is no compression of the tissues. When the foot is flat or pronated the sinus tarsi is compressed and can cause pain (sinus tarsi syndrome.

Flat foot sinus tarsi pain

In a normal arched foot the 1st metatarsal is plantar flexed. This allows the great toe to function normally and there is no jamming.
Normal Foot toe functionNormal Foot toe functionIn a flat arched foot the 1st metatarsal is dorsiflexed. This causes dorsal jamming of the great toe

Flat foot toe functionFlat foot toe function

Orthotic Treatment of flat feet?

There are a number of different orthotic designs available for flat feet. Most orthotic designs are simply arch supports.

These are not ideal for the flat foot, often only irritating the arch of the foot.

This is due to the subtalar joint axis position. The diagram below shoes the axis of the subtalar joint.

Subtalar joint and orthoticsThe most appropriate design for a flat foot is a DHC (Deep Heel Cup) rearfoot orthotic this type of orthotic applies pressure on the red area which increases the arch of the foot without causing discomfort as with most midfoot orthotics.

Our lead podiatrist has spent the last 5 years designing a specific orthotic that provides greater rearfoot support and control called Modulign click here to find out more

Orthotic for flat feetDHC Orthotic DHC Orthotic

DHC orthotic – Deep heel cup orthotic  provides ultimate rear foot control


The Ankle, Foot and Orthotic Centre’s Northcote Podiatrists can help you with all lower limb complaints, including Flat Feet Make an appointment to get your foot and ankle pain under control.

Expert Podiatrists for the treatment of Flat Feet servicing the areas of Northcote, Thornbury, Fitzroy, North Fitzroy, Carlton, North Carlton, Alphington, Fairfield, Brunswick, Coburg and Preston

Call The Ankle and Foot Centre in Northcote for further advice on professional management and treatment options.