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:
- Advise appropriate shoes
- Advise exercises
- Consider prescribing orthotics
- Consider a period of immobilisation
- Consider prescribing a custom made ankle foot orthotic
- Advise on surgery
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.