Flat foot (pes planus), which is also referred to as flat feet or fallen arches, is a type of deformity in the foot where there is little to no arch present. It can affect only one foot but typically is found in both feet.
We all start out in life with flat feet. At birth, all babies have flat feet and their arches begin to develop during the early years of childhood until fully formed around the age of six. For some children, roughly two out of ten, the arch does not develop as they grow into adulthood. For many adults, their arches later “fall” or collapse. This can be a mild condition that causes only occasional discomfort, but, for many people, fallen arches can result in pain, not only in the feet but also the ankles, calves, knees, hips, and even up into the lower back.
One of the first pieces of advice given for maintaining healthy feet is to make sure to wear properly fitting shoes. Purchasing shoes that fit and are comfortable can be difficult and expensive for someone with fallen arches. Besides the extra arch support required, the lack of an arch can often affect someone’s natural walking gait, forcing adjustments that result in pronation issues. This tends to lead to uneven wear on the soles and requires more frequent replacements.
Types of Flat Foot
There are different ways to classify flat foot, mostly based on whether it is congenital or develops later in life and on the degree of the deformity. These types include:
- Vertical talus – this describes a congenital disability in which the arch never develops. It is sometimes referred to as “rocker-bottom foot” because the baby’s foot looks like the rocker portion of a rocking chair.
- Adult-acquired flat foot deformity (AAFD) – this is the fallen arch, an arch that has collapsed. It can have a variety of causes, one of the most common being damage to the supporting posterior tibial tendon.
- Flexible flat foot – this is the most common form of the condition and is defined by the arch being visible when not standing and then disappearing when weight is put on the foot.
- Rigid flat foot – there is no appearance of an arch with rigid flat foot, standing or sitting. The foot cannot be manipulated into a normal alignment.
Causes of Flat Foot
There are a variety of causes for flat foot. Birth defects and conditions which affect the nerves and muscles of newborns can be the cause. Some of those on this list include spina bifida, muscular dystrophy, and cerebral palsy.
For arches that have fallen or collapsed later in life, some of the most common risk factors are overuse, aging, injury or trauma, inappropriate or poorly fitting footwear, obesity, diabetes, rheumatoid arthritis, or pregnancy.
Treatment options will vary by individual and depend on the severity of the condition and how much it is affecting your lifestyle. Most people will benefit from some combination of non-surgical methods which will usually include:
- Supportive, properly fitted footwear with sufficient arch support and cushioning
- Orthotics, custom or over-the-counter
- Shoe inserts
- Pain relief with rest, ice, elevation, and over-the-counter medications
- Losing weight, which reduces pressure and impact on the feet
- Stretching exercises
- Physical therapy
- Limiting high-impact activities, like running on hard surfaces and sports, like basketball, soccer, and tennis
- Avoiding shoes that strain the arches, especially high heels and those that are too flat
Flat Foot Surgery
For more severe cases of flatfoot that have not responded to non-surgical treatment, there are a variety of surgical procedures that your orthopedic surgeon can choose from to reduce pain, correct misalignments of the foot, and restore balance and more normal pressure while standing and walking. The method chosen will be determined based on the type and extent of the deformity and may include a combination of more than one of the following:
- Achilles lengthening – this procedure, which involves the stretching or lengthening of the Achilles tendon is done for adult-acquired flatfoot deformity due to the Achilles tendon becoming contracted and tightened.
- Medializing calcaneal osteotomy – sometimes referred to as a “heel slide”, the medializing calcaneal osteotomy helps to restore a fallen arch by cutting the heel bone in such a way that it can be slid back into proper alignment. The heel bone is then held in position with staples, screws, or, if necessary, a steel plate.
- Tendon transfers – this surgery involves moving or “transferring” another tendon to add strength to one that has been damaged. Typically, it is the flexor digitorum longus tendon, which is responsible for flexing the toes, that is transferred to perform the function of a damaged posterior tibial tendon.
- Ligament repairs – this typically involves repairs to the spring and deltoid ligaments responsible for helping to keep the foot and ankle in proper alignment.
- Lateral column lengthening – cadaver bones or metal wedges are often used to increase the length of the calcaneus bone to correct the deformity that is causing the deformity and fallen arch.
- Cotton (medial cuneiform) osteotomy – in this procedure the medial cuneiform bone is cut and spread apart using a piece of bone or metal arch. This can help to recreate an arch.
- Midfoot fusion – fusing one or more of the midfoot joints is sometimes performed in an effort to restore the arch.
- Subtalar fusion – this procedure involves the fusing of the bones that meet to form the subtalar joint, the talus and the calcaneus bones and is done when the condition is more severe.
- Double or triple arthrodesis – in the most severe cases or when arthritis is involved, two or three joints may be fused. In double arthrodesis, this would be the subtalar and talonavicular joints and in triple arthrodesis, the calcaneocuboid joint would also be fused.
Depending upon the procedure, patients may go home with their foot in a splint or cast the same day or remain overnight. The foot should be elevated for the two weeks following surgery, at which time the sutures will be removed and the foot put into a protective boot or new cast.
There should not be any weight put on the affected foot for 6 to 8 weeks following surgery. At 10 to 12 weeks, full weight-bearing activities may be resumed, although, for some, this can take longer. A regular shoe may be worn around the 10-week mark, but full recovery can take a year or longer.