A variety of foot problems can lead to adult acquired flatfoot deformity (AAFD), a condition that results in a fallen arch with the foot pointed outward. Most people - no matter what the cause of their flatfoot - can be helped with orthotics and braces. In patients who have tried orthotics and braces without any relief, surgery can be a very effective way to help with the pain and deformity. This article provides a brief overview of the problems that can result in AAFD. Further details regarding the most common conditions that cause an acquired flatfoot and their treatment options are provided in separate articles. Links to those articles are provided.
There are many different causes of flat feet, which can be separated into two main categories. The first category, congenital flat foot, is a condition that one is born with or is predisposed to at birth. This type includes the completely asymptomatic, pediatric flexible flat foot-by far the most common form of congenital flat foot. Flexible means that an arch is present until weight is put on the foot, at which time the arch disappears. This foot type is a result of the fact that all people are born with different physical features. Some people have bigger noses than others, just as some people have flatter feet (of course, there is no known correlation between the two). Any alteration in the many building blocks of the foot can influence its shape. At the other end of the spectrum, yet within the same category of congenital flat foot, exist several rare, more severe forms of flat foot. These severe conditions include Vertical Talus, Congenital Calcaneal Valgus, and Tarsal Coalitions - all of which are more rigid (no arch with or without weight on the foot) and definitely symptomatic. Luckily, these are much less common, but can usually be identified by specialists at the time of presentation and treated appropriately. The second category, acquired flat foot, develops over time, rather than at birth. Many different factors can contribute to the development of flat feet. These include the types of shoes a child wears, a child's sitting or sleeping positions, compensation for other abnormalities further up the leg, or more severe factors such as rupture of ligaments or tendons in the foot. Very commonly, the reason for flat feet is that the foot is compensating for a tight Achilles tendon. If the Achilles tendon is tight, then it causes the foot to point down, or to plantarflex (as occurs when stepping on the accelerator of your car). Even minimal amounts of plantarflexion can simulate a longer leg on that particular side, assuming that the other foot is in the normal position. The body therefore tries to compensate by pronating, or flattening out the arch, thereby making up for the perceived extra length on the affected side.
Flat feet don't usually cause problems, but they can put a strain on your muscles and ligaments (ligaments link two bones together at a joint). This may cause pain in your legs when you walk. If you have flat feet, you may experience pain in any of the following areas, the inside of your ankle, the arch of your foot, the outer side of your foot, the calf, the knee, hip or back. Some people with flat feet find that their weight is distributed unevenly, particularly if their foot rolls inwards too much (overpronates). If your foot overpronates, your shoes are likely to wear out quickly. Overpronation can also damage your ankle joint and Achilles tendon (the large tendon at the back of your ankle).
People who have flat feet without signs or symptoms that bother them do not generally have to see a doctor or podiatrist about them. However, if any of the following occur, you should see your GP or a podiatrist. The fallen arches (flat feet) have developed recently. You experience pain in your feet, ankles or lower limbs. Your unpleasant symptoms do not improve with supportive, well-fitted shoes. Either or both feet are becoming flatter. Your feet feel rigid (stiff). Your feet feel heavy and unwieldy. Most qualified health care professionals can diagnose flat feet just by watching the patient stand, walk and examining his/her feet. A doctor will also look at the patient's medical history. The feet will be observed from the front and back. The patient may be asked to stand on tip-toe while the doctor examines the shape and functioning of each foot. In some cases the physician may order an X-ray, CT (computed tomography) scan, or MRI (magnetic resonance imaging) scan.
Non Surgical Treatment
Physiotherapists will carry out a detailed biomechanical assessment of your feet and lower limb. Once the causes have been identified a number of treatment methods may be used to help relieve pain and restore function in the feet including the use of custom made orthotics to support the foot and offload the areas which are painful, strengthening exercises for weakened muscles and tendons in the arch, and massage and mobilisation techniques to help mobilise stiff tissue and joints in the foot.
Procedures may include the following. Fusing foot or ankle bones together (arthrodesis). Removing bones or bony growths, also called spurs (excision). Cutting or changing the shape of the bone (osteotomy). Cleaning the tendons' protective coverings (synovectomy). Adding tendon from other parts of your body to tendons in your foot to help balance the "pull" of the tendons and form an arch (tendon transfer). Grafting bone to your foot to make the arch rise more naturally (lateral column lengthening).
Patients may go home the day of surgery or they may require an overnight hospital stay. The leg will be placed in a splint or cast and should be kept elevated for the first two weeks. At that point, sutures are removed. A new cast or a removable boot is then placed. It is important that patients do not put any weight on the corrected foot for six to eight weeks following the operation. Patients may begin bearing weight at eight weeks and usually progress to full weightbearing by 10 to 12 weeks. For some patients, weightbearing requires additional time. After 12 weeks, patients commonly can transition to wearing a shoe. Inserts and ankle braces are often used. Physical therapy may be recommended. There are complications that relate to surgery in general. These include the risks associated with anesthesia, infection, damage to nerves and blood vessels, and bleeding or blood clots. Complications following flatfoot surgery may include wound breakdown or nonunion (incomplete healing of the bones). These complications often can be prevented with proper wound care and rehabilitation. Occasionally, patients may notice some discomfort due to prominent hardware. Removal of hardware can be done at a later time if this is an issue. The overall complication rates for flatfoot surgery are low.