Overview Most flat feet are not painful, particularly those flat feet seen in children. In the adult acquired flatfoot, pain occurs because soft tissues (tendons and ligaments) have been torn. The deformity progresses or worsens because once the vital ligaments and posterior tibial tendon are lost, nothing can take their place to hold up the arch of the foot. The painful, progressive adult acquired flatfoot affects women four times as frequently as men. It occurs in middle to older age people with a mean age of 60 years. Most people who develop the condition already have flat feet. A change occurs in one foot where the arch begins to flatten more than before, with pain and swelling developing on the inside of the ankle. Why this event occurs in some people (female more than male) and only in one foot remains poorly understood. Contributing factors increasing the risk of adult acquired flatfoot are diabetes, hypertension, and obesity. Causes There are a number of theories as to why the tendon becomes inflamed and stops working. It may be related to the poor blood supply within the tendon. Increasing age, inflammatory arthritis, diabetes and obesity have been found to be causes. Symptoms The types of symptoms that may indicate Adult-Acquired Flat Foot Deformity include foot pain that worsens over time, loss of the arch, abnormal shoe wear (excessive wearing on the inner side of shoe from walking on the inner side of the foot) and an awkward appearance of the foot and ankle (when viewed from behind, heel and toes appear to go out to the side). It is important that we help individuals recognize the early symptoms of this condition, as there are many treatment options, depending upon the severity, the age of the patient, and the desired activity levels. Diagnosis Starting from the knee down, check for any bowing of the tibia. A tibial varum will cause increased medial stress on the foot and ankle. This is essential to consider in surgical planning. Check the gastrocnemius muscle and Achilles complex via a straight and bent knee check for equinus. If the range of motion improves to at least neutral with bent knee testing of the Achilles complex, one may consider a gastrocnemius recession. If the Achilles complex is still tight with bent knee testing, an Achilles lengthening may be necessary. Check the posterior tibial muscle along its entire course. Palpate the muscle and observe the tendon for strength with a plantarflexion and inversion stress test. Check the flexor muscles for strength in order to see if an adequate transfer tendon is available. Check the anterior tibial tendon for size and strength. Non surgical Treatment Get treated early. There is no recommended home treatment. While in stage one of the deformity, rest, a cast, and anti-inflammatory therapy can help you find relief. This treatment is followed by creating custom-molded foot orthoses and orthopedic footwear. These customized items are critical in maintaining the stability of the foot and ankle. Once the tendon has stretched and deformity is visible, the chances of success for non-surgical treatment are significantly lower. In a small percentage of patients, total immobilization may arrest the progression of the deformity. A long-term brace known as an ankle foot orthosis is required to keep the deformity from progressing. The Richie Brace, a type of ankle foot orthosis, shows significant success as a treatment for stage two posterior tibial dysfunction. It is a sport-style brace connected to a custom corrected foot orthodic that fits into most lace-up footwear (including athletic shoes). It is also light weight and more cosmetically appealing than traditionally prescribed ankle foot orthosis. The Arizona Brace, California Brace or Gauntlet Brace may also be recommended depending on your needs. Surgical Treatment The indications for surgery are persistent pain and/or significant deformity. Sometimes the foot just feels weak and the assessment of deformity is best done by a foot and ankle specialist. If surgery is appropriate, a combination of soft tissue and bony procedures may be considered to correct alignment and support the medial arch, taking strain off failing ligaments. Depending upon the tissues involved and extent of deformity, the foot and ankle specialist will determine the necessary combination of procedures. Surgical procedures may include a medial slide calcaneal osteotomy to correct position of the heel, a lateral column lengthening to correct position in the midfoot and a medial cuneiform osteotomy or first metatarsal-tarsal fusion to correct elevation of the medial forefoot. The posterior tibial tendon may be reconstructed with a tendon transfer. In severe cases (stage III), the reconstruction may include fusion of the hind foot,, resulting in stiffness of the hind foot but the desired pain relief. In the most severe stage (stage IV), the deltoid ligament on the inside of the ankle fails, resulting in the deformity in the ankle. This deformity over time can result in arthritis in the ankle.