Flat foot (low arch)
Many people think they have a flat foot when this is rarely the
case. A true flat foot exists when the bones of the arch of the
foot have collapsed and are flat on the floor. Most people have a
degree of arch in the foot when they are not standing although this
does vary between people and racial groups. When the foot is loaded
on standing/walking, the bones of the arch lower giving the
appearance of a flat foot. This motion is known as pronation and the degree
of pronation that occurs varies between individuals.
Even when the pronation occurs, most people still retain a
degree of arch on standing. If the arch collapses completely then
this is known as a flexible flat foot. However, if the arch is flat
both sitting and standing, this is known as a rigid flat foot.
What causes a flatfoot?
Many people who have a flat foot were born with a mobile flat
foot. Although the foot may remain mobile it can become more rigid
with increasing age.
People with severely pronated feet are predisposed to straining
the Tibialis posterior tendon on the inside of the ankle as it
tries to resist this movement. With time, the tendon can stretch,
tear or rupture allowing the flat foot to worsen. Injury/trauma to
the rear foot can result in an abnormal position or arthritis and
cause a flat foot.
There are some medical conditions (e.g. rheumatoid arthritis)
which can predispose to inflammation of the tendon or arthritis of
the major joints of the rear foot which can result in a flat
foot.
Will it get worse?
Not necessarily. However, with time, arthritis can develop in
the joints of the foot and there may be overuse of the tendons and
muscles.
What are the common symptoms?
- Low / flat arch
- Pain / discomfort in the foot, leg or back
- Associated deformities (e.g. bunions, arthritis)
- Difficulty in shoes
- Difficulty in walking
- Stiffness in the foot
- Corn / callous formation
How is it recognised?
Clinical examination and a detailed history allow diagnosis.
X-rays help to evaluate the extent of the deformity and any
arthritis within the joint. Specialist scans help to evaluate the
tendons and joints. A detailed gait analysis can help
to diagnose the contributing factors to the flat foot.
What can I do to reduce the pain?
There are several things that you can do to try and relieve your
symptoms:
- Wear good fitting shoes
- Perform exercises to keep the muscles flexible and strong
- Avoid high heels
- Wear a pad over any prominent deformities
- See a podiatrist
What will a podiatrist do?
If simple measures do not reduce your symptoms, there are other
options:
The way in which your foot loads during walking can place
increased stress on the foot and this can be controlled by special
shoe inserts (orthotics). Whilst these are unlikely to resolve
established deformity they may help reduce discomfort. In acute
cases, a period of immobilisation may be required and severe cases
may need an ankle foot orthosis.
Will this cure the problem?
In many cases, the conservative treatments are sufficient to
resolve the symptoms and prevent tendon damage. However, they will
not correct the foot position and there will always be the risk of
further problems, especially in more severe cases.
What will happen if I leave this alone?
If there are symptoms with a flat foot, the likelihood is that
these will get worse if left alone. This runs the risk of further
deformity, tendon/joint damage and pain.
How can I cure the deformity?
The only effective way of correcting the deformity is to have an
operation. However, this is usually extensive surgery with a long
recovery period and should only be considered if all of the
conservative treatments have failed.
More information can be found under Tibialis posterior tendon
dysfunction.