Adult Acquired Flatfoot (Posterior Tibial Tendon Dysfunction) is a painful, progressive deformity in adults. It results from a gradual stretch (attenuation) of the tibialis posterior tendon and the ligaments that support your foot?s arch. This stretching causes the tendon to lose strength and function. Many people have flat feet and do not experience pain. However, pain occurs with Adult Acquired Flatfoot because the tendons and ligaments have been torn. Once the vital ligaments and posterior tibial tendon are lost, there is no longer anything holding the arch of the foot in place.
Women are affected by Adult Acquired Flatfoot four times more frequently than men. Adult Flatfoot generally occurs in middle to older age people. Most people who acquire the condition already have flat feet. One arch begins to flatten more, then pain and swelling develop on the inside of the ankle. This condition generally affects only one foot. It is unclear why women are affected more often than men. But factors that may increase your risk of Adult Flatfoot include diabetes, hypertension, and obesity.
Often, this condition is only present in one foot, but it can affect both. Adult acquired flatfoot symptoms vary, but can swelling of the foot's inner side and aching heel and arch pain. Some patients experience no pain, but others may experience severe pain. Symptoms may increase during long periods of standing, resulting in fatigue. Symptoms may change over time as the condition worsens. The pain may move to the foot's outer side, and some patients may develop arthritis in the ankle and foot.
Looking at the patient when they stand will usually demonstrate a flatfoot deformity (marked flattening of the medial longitudinal arch). The front part of the foot (forefoot) is often splayed out to the side. This leads to the presence of a ?too many toes? sign. This sign is present when the toes can be seen from directly behind the patient. The gait is often somewhat flatfooted as the patient has the dysfunctional posterior tibial tendon can no longer stabilize the arch of the foot. The physician?s touch will often demonstrate tenderness and sometimes swelling over the inside of the ankle just below the bony prominence (the medial malleolus). There may also be pain in the outside aspect of the ankle. This pain originates from impingement or compression of two tendons between the outside ankle bone (fibula) and the heel bone (calcaneus) when the patient is standing.
Non surgical Treatment
Conservative (nonoperative) care is advised at first. A simple modification to your shoe may be all that???s needed. Sometimes purchasing shoes with a good arch support is sufficient. For other patients, an off-the-shelf (prefabricated) shoe insert works well. The orthotic is designed specifically to position your foot in good alignment. Like the shoe insert, the orthotic fits inside the shoe. These work well for mild deformity or symptoms. Over-the-counter pain relievers or antiinflammatory drugs such as ibuprofen may be helpful. If symptoms are very severe, a removable boot or cast may be used to rest, support, and stabilize the foot and ankle while still allowing function. Patients with longer duration of symptoms or greater deformity may need a customized brace. The brace provides support and limits ankle motion. After several months, the brace is replaced with a foot orthotic. A physical therapy program of exercise to stretch and strengthen the foot and leg muscles is important. The therapist will also show you how to improve motor control and proprioception (joint sense of position). These added features help prevent and reduce injuries.
Surgical correction is dependent on the severity of symptoms and the stage of deformity. The goals of surgery are to create a more functional and stable foot. There are multiple procedures available to the surgeon and it may take several to correct a flatfoot deformity. Usually surgical treatment begins with removal of inflammatory tissue and repair of the posterior tibial tendon. A tendon transfer is performed if the posterior tibial muscle is weak or the tendon is badly damaged. The most commonly used tendon is the flexor digitorum longus tendon. This tendon flexes or moves the lesser toes downward. The flexor digitorum longus tendon is utilized due to its close proximity to the posterior tibial tendon and because there are minimal side effects with its loss. The remainder of the tendon is sutured to the flexor hallucis longus tendon that flexes the big toe so that little function is loss.