If you have flatfeet (pes planus), the arch on the inside of your feet is flattened. Flatfeet usually don’t cause problems and are not inherently ‘abnormal’. However, flatfeet can contribute to problems in your feet, ankles and knees. Simple corrective devices are available to help prevent complications of flatfeet.
With flatfeet, you may experience the following signs and symptoms:
- A flat look to one or both of your feet
- Uneven shoe wear and collapse of your shoe toward the inside of your flat foot
- Lower leg pain or weakness
- Pain on the inside of your ankle
- Swelling along the inside of your ankle
- Foot pain
Not all feet are the same
Flat feet are normal in infants and toddlers, because the foot's arch hasn't yet developed. Most people's arches develop throughout childhood, but some people never develop arches. This is a normal variation in foot type, and people without arches may or may not have problems.
Arches can also fall over time. Years of wear and tear can weaken the posterior tibial tendon, which runs along the inside of your ankle, from above your ankle to your arch. The posterior tibial tendon is the main support structure for the arch. An overload to this tendon can cause inflammation of the tendon (tendinitis) and even tearing of the tendon. Once the tendon is damaged the foot's arch loses support and can flatten.
You may lose support in your arches due to:
Ongoing stresses in your feet. One of these stresses may be long-term wearing of high heels, which can affect your Achilles tendon and change the mechanics of your ankles. Compensation by the posterior tibial tendon may eventually cause it to break down and your arches to fall.
- Traumatic injury to your foot or ankle
- Rheumatoid arthritis
Can be made with a standard orthopedic examination and medical history. To view the interior structure and bones of your foot, your doctor may request an imaging test of your foot, which may include an X-ray, a computerized tomography (CT) scan or a magnetic resonance imaging (MRI) scan.
If the disorder is causing you problems, you may be able to reduce foot pain by:
- Custom-designed arch supports - Commonly called foot orthotics, these are interchangeable among your shoes and may provide more support because they're molded to the contours of your feet.
- Wedge, in addition to an orthotic - If you have tendinitis of the posterior tibial tendon, you may need to insert a wedge along the inside edge of the orthotic to take some of the load off the tendon tissue.
- Additional foot support - Your doctor also may advise that you wear an ankle brace or a walking boot for a time until the tendon inflammation subsides.
- Surgery - In severe cases, surgery is neccessary. Surgery can include a combination of "tendon transfer and bone realignment" (osteotomy) to "fusion" (arthrodesis) surgery. The type of surgery recommended will depend on the presence of arthritis, stiffness, and the age and activity level of the patient.