Some people have always had flat feet from a young age. Unfortunately as people reach their fifties they will suddenly have one foot with a flatter arch than the other foot. This situation is termed adult acquired flatfoot. Adult acquired flatfoot is a painful condition occurring in one foot. The common patient profile is a female over the age of 50 with pre-existing flatfeet, high blood pressure, high cholesterol, diabetes and obesity. All of these underlying problems will lead to a weakening of the support structures of the arch. If you have adult acquired flat foot you will not be able to lift your heel off the ground while standing on one leg. Adult acquired flatfoot may develop due to trauma or degeneration of major tendons ankle & foot. Weakness or paralysis of leg muscles can also create a flatfoot deformity.
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.
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.
Examination by your foot and ankle specialist can confirm the diagnosis for most patients. An ultrasound exam performed in the office setting can evaluate the status of the posterior tibial tendon, the tendon which is primarily responsible for supporting the arch structure of the foot.
Non surgical Treatment
Depending on the stage of the deformity and patient?s functional goals, various treatment options are available. Some patients improve with conservative care which includes rest and immobilization, shoe modifications, orthoses and bracing, or physical therapy. Surgery might be warranted for advanced stages of the condition. Often a combination of procedures including tendon and muscle augmentation, tendon transfers, realigning of bones or fusion of certain joints might be necessary in more advanced cases. Your doctor will evaluate and recommend an individualized plan of care with your specific needs in mind.
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.