Adult acquired flatfoot deformity, primarily posterior tibial tendon dysfunction, in many cases can be successfully managed with conservative treatment modalities including early immobilization, long-term bracing, physi?cal therapy, and anti-inflam?matory medications. Adult acquired flatfoot deformity (AAFD), the painful flatfoot deformity in adults, is a major cause of disability for a patient and can be a challenge for foot and ankle specialists.
The cause of posterior tibial tendon insufficiency is not completely understood. The condition commonly does not start from one acute trauma but is a process of gradual degeneration of the soft tissues supporting the medial (inner) side of the foot. It is most often associated with a foot that started out somewhat flat or pronated (rolled inward). This type of foot places more stress on the medial soft tissue structures, which include the posterior tibial tendon and ligaments on the inner side of the foot. Children nearly fully grown can end up with flat feet, the majority of which are no problem. However, if the deformity is severe enough it can cause significant functional limitations at that age and later on if soft tissue failure occurs. Also, young adults with normally aligned feet can acutely injure their posterior tibial tendon from a trauma and not develop deformity. The degenerative condition in patients beyond their twenties is different from the acute injuries in young patients or adolescent deformities, where progression of deformity is likely to occur.
Not everyone with adult flatfoot has problems with pain. Those who do usually experience it around the ankle or in the heel. The pain is usually worse with activity, like walking or standing for extended periods. Sometimes, if the condition develops from arthritis in the foot, bony spurs along the top and side of the foot develop and make wearing shoes more painful. Diabetic patients need to watch for swelling or large lumps in the feet, as they may not notice any pain. They are also at higher risk for developing significant deformities from their flatfoot.
Although you can do the "wet test" at home, a thorough examination by a doctor will be needed to identify why the flatfoot developed. Possible causes include a congenital abnormality, a bone fracture or dislocation, a torn or stretched tendon, arthritis or neurologic weakness. For example, an inability to rise up on your toes while standing on the affected foot may indicate damage to the posterior tibial tendon (PTT), which supports the heel and forms the arch. If "too many toes" show on the outside of your foot when the doctor views you from the rear, your shinbone (tibia) may be sliding off the anklebone (talus), another indicator of damage to the PTT. Be sure to wear your regular shoes to the examination. An irregular wear pattern on the bottom of the shoe is another indicator of acquired adult flatfoot. Your physician may request X-rays to see how the bones of your feet are aligned. Muscle and tendon strength are tested by asking you to move the foot while the doctor holds it.
Non surgical Treatment
Nonoperative treatment of posterior tibial tendon dysfunction can be successful with the Arizona AFO brace, particularly when treatment is initiated in the early stages of the disease. This mandates that the orthopedist has a high index of suspicion when evaluating patients to make an accurate diagnosis. Although there is a role for surgical management of acquired flat feet, a well-fitted, custom-molded leather and polypropylene orthosis can be effective at relieving symptoms and either obviating or delaying any surgical intervention. In today's climate of patient satisfaction directed health care, a less invasive treatment modality that relieves pain may prove to be more valuable than similar pain relief that is obtained after surgery. Questions regarding the long-term results of bracing remain unanswered. Future studies are needed to determine if disease progression and arthrosis occur despite symptomatic relief with a brace. Furthermore, age- and disease stage-matched control groups who are randomized to undergo surgery or bracing are necessary to compare these different treatment modalities.
If conservative treatment fails surgical intervention is offered. For a Stage 1 deformity a posterior tibial tendon tenosynovectomy (debridement of the tendon) or primary repair may be indicated. For Stage 2 a combination of Achilles lengthening with bone cuts, calcaneal osteotomies, and tendon transfers is common. Stage 2 flexible PTTD is the most common stage patients present with for treatment. In Stage 3 or 4 PTTD isolated fusions, locking two or more joints together, maybe indicated. All treatment is dependent on the stage and severity at presentation with the goals and activity levels of the patient in mind. Treatment is customized to the individual patient needs.