One in four adults in the U.S. has adult acquired flatfoot deformity, which may begin during childhood or be acquired with age. The foot may be flat all the time or may lose its arch when the person stands. The most common and serious cause of flat foot is Posterior Tibial Tendon Dysfunction, in which the main tendon that supports the arch gradually weakens.
Flat feet causes greater pressure on the posterior tibial tendon than normal. As the person with flat feet ages, the muscles, tendons and ligaments weaken. Blood supplies diminish as arteries narrow. These conditions are magnified for obese patients because of their increased weight and atherosclerosis. Finally, the tendon gives out or tears. Most of the time, this is a slow process. Once the posterior tibial tendon and ligaments stretch, body weight causes the bones of the arch to move out of position. The foot rotates inward (pronation), the heel bone is tilted to the inside, and the arch appears collapsed. In some cases, the deformity progresses until the foot dislocates outward from the ankle joint.
Many patients with this condition have no pain or symptoms. When problems do arise, the good news is that acquired flatfoot treatment is often very effective. Initially, it will be important to rest and avoid activities that worsen the pain.
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
Initial treatment is based on the degree of deformity and flexibility at initial presentation. Conservative treatment includes orthotics or ankle foot orthoses (AFO) to support the posterior tibial tendon (PT) and the longitudinal arch, anti-inflammatories to help reduce pain and inflammation, activity modification which may include immobilization of the foot and physical therapy to help strengthen and rehabilitate the tendon.
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.